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<h1 class="title">Customizing <span class="code">weewx</span><br />
Version 1.10</h1>
<h1>Table of contents</h1>
<ol>
<li><a href="#Introduction">Introduction</a></li>
<li><a href="#Opportunities_for_customizing_reports">Opportunities for customizing
reports</a></li>
<li><a href="#Reference:_The_Standard_skin_configuration_file">Reference: The
Standard skin configuration file</a></li>
<li><a href="#Customizing_the_weewx_service_engine">Customizing the
<span class="code">weewx</span> service engine</a></li>
<li><a href="#Types">Appendix A: Types</a></li>
<li><a href="#Units">Appendix B: Units</a></li>
<li><a href="#Statistical_types">Appendix C: Statistical aggregations</a></li>
</ol>
<h1>1. <a name="Introduction">Introduction</a></h1>
<p>This document covers the customization of weewx. It assumes that you have read
and are reasonably familiar with the <a href="readme.htm">Users Guide</a>.</p>
<p>It starts with an overview of the architecture of weewx. If you are only interested
in customizing the generated skin reports you can probably skip the overview and
proceed directly to the section <em>
<a href="#Reference:_The_Standard_skin_configuration_file">The Standard skin configuration
file</a></em>. With this approach you can easily add new plot images, change the
titles of images, change the units used in the reports, and so on.</p>
<p>However, if your goal is a specialized application such as adding alarms, RSS
feeds, etc., then it would be worth your while to read about the internal architecture
and how to customize it.</p>
<h2>Warning</h2>
<p><span class="code">weewx</span> is still an experimental system and, as such,
its internal design is subject to change. Be prepared to do updates to any code
or customization you do!</p>
<h2>Overview of the weewx architecture</h2>
<p>At a high-level, <span class="code">weewx</span> consists of an engine class
called <span class="code">StdEngine</span>. It is responsible for loading any &quot;<em>services</em>&quot;
that are to be run and arranging for them to be called when key events occur, such
as the arrival of LOOP data. The default install of <span class="code">weewx</span>
includes the following services:</p>
<table align="center" style="width: 60%">
<tr>
<td><strong>Service</strong></td>
<td><strong>Function</strong></td>
</tr>
<tr>
<td><span class="code">weewx.wxengine.StdCalibrate</span></td>
<td>Adjust new LOOP and archive packets using calibration expressions.</td>
</tr>
<tr>
<td><span class="code">weewx.wxengine.StdQC</span></td>
<td>Check quality of incoming data, making sure values fall within a specified
range.</td>
</tr>
<tr>
<td><span class="code">weewx.wxengine.StdArchive</span></td>
<td>Archive any new data to the SQL databases.</td>
</tr>
<tr>
<td><span class="code">weewx.wxengine.StdTimeSynch</span></td>
<td>Arrange to have the clock on the station synchronized at regular intervals.</td>
</tr>
<tr>
<td><span class="code">weewx.wxengine.StdPrint</span></td>
<td>Print out new LOOP and archive packets on the console.</td>
</tr>
<tr>
<td><span class="code">weewx.wxengine.StdRESTful</span></td>
<td>Start a thread to manage
<a href="http://en.wikipedia.org/wiki/Representational_State_Transfer">RESTful</a>
(simple stateless client-server protocols) connections; such as those used
by the Weather Underground or PWSweather.</td>
</tr>
<tr>
<td><span class="code">weewx.wxengine.StdReportService</span></td>
<td>Launch a new thread to do report processing after a new archive record
arrives. Reports do things such as generate HTML files, generate images,
or FTP files to a web server. New reports can be added easily by the user.</td>
</tr>
</table>
<p>It is easy to extend old services or to add new ones. The source distribution
includes an example new service called &quot;<span class="code">MyAlarm</span>,&quot; which
sends an email when an arbitrary expression evaluates <span class="code">True</span>.
These advanced topics are covered later in the section <em>
<a href="#Customizing_the_weewx_service_engine">Customizing the weewx service engine</a></em>.</p>
<h3><a name="The_standard_reporting_service,_StdReportService">The standard reporting
service, <span class="code">StdReportService</span></a></h3>
<p>For the moment, we focus on the last service, <span class="code">weewx.wxengine.StdReportService</span>,
the standard service for creating reports. This will be what most users want to
customize even if it means just changing a few options.</p>
<h4>Reports</h4>
<p>The Standard Report Service runs zero or more <em>Reports.</em> Which ones are
set in the weewx configuration file <span class="code">weewx.conf</span>, in section
<span class="code">[Reports]</span>.</p>
<p>The default distribution of weewx includes two reports:</p>
<table align="center" style="width: 60%">
<tr>
<td><strong>Report</strong></td>
<td><strong>Default functionality</strong></td>
</tr>
<tr>
<td class="code">StandardReport</td>
<td>Generates day, week, month and year &quot;to-date&quot; summaries in HTML, as
well as the plot images to go along with them. Also generates NOAA monthly
and yearly summaries. </td>
</tr>
<tr>
<td class="code">FTP</td>
<td>Arranges to upload everything in the <span class="code">public_html</span>
subdirectory up to a remote webserver.</td>
</tr>
</table>
<p>Note that the FTP &quot;report&quot; is kind of a funny report in that it doesn&#39;t actually
generate anything. Instead, it uses the reporting service engine to arrange for
things to be FTP&#39;d to a remote server.</p>
<h4>Skins<br />
</h4>
<p>Each report has a <em>Skin</em> associated with it. For most reports, the relationship
with the skin is an obvious one: it contains the templates, any auxiliary files
such as background GIFs or CSS style sheets, and a <em>skin configuration file</em>,
<span class="code">skin.conf</span>. If you will, the skin controls the <em>look
and feel </em>of the report. Note that more than one report can use the same skin.
For example, you might want to run a report that uses US Customary units, then run
another report against the same skin, but using metric units and put the results
in a different place. All this is possible by either overriding configuration options
in the weewx configuration file <span class="code">weewx.conf</span> or the skin
configuration file <span class="code">skin.conf</span>.</p>
<p>Like all reports, the FTP &quot;Report&quot; also uses a skin, and includes a skin configuration
file, although it is quite minimal.</p>
<p>Skins live in their own subdirectory located in <span class="code"><em>$HTML_ROOT</em>/skins</span>.</p>
<h4>Generators</h4>
<p>To create their output, skins rely on one or more <em>Generators, </em>code that
actually create useful things such as HTML files or plot images. They can also copy
files around or FTP them to remote locations. The default install of
<span class="code">weewx </span>includes the following generators:</p>
<table align="center" style="width: 60%">
<tr>
<td><strong>Generator</strong></td>
<td><strong>Function</strong></td>
</tr>
<tr>
<td class="code">weewx.filegenerator.FileGenerator</td>
<td>Generates files from templates. Used to generate HTML and text files.</td>
</tr>
<tr>
<td class="code">weewx.imagegenerator.ImageGenerator</td>
<td>Generates graph plots.</td>
</tr>
<tr>
<td><span class="code">weewx.reportengine.FtpGenerator</span></td>
<td>Uploads data to a remote server using FTP.</td>
</tr>
<tr>
<td><span class="code">weewx.reportengine.CopyGenerator</span></td>
<td>Copies files locally.</td>
</tr>
</table>
<p>Note that the two generators <span class="code">FtpGenerator </span>and
<span class="code">CopyGenerator </span>don&#39;t actually generate anything to do with
the presentation layer. Instead, they just move files around. </p>
<p>Which generators are to be run for a given skin is specified in the skin&#39;s configuration
file <span class="code">skin.conf</span>.</p>
<h2><a name="Databases">Databases</a></h2>
<p>There are two databases used in weewx, both <a href="http://www.sqlite.org/">
SQLITE3</a> databases:</p>
<ul>
<li>The <em>archive database</em>, nominally located at <span class="code">
<em>$WEEWX_ROOT</em>/archive/weewx.sdb</span>. It is a big flat table, one record
for each archive interval, keyed by <span class="code">dateTime</span>, the
time at the end of the archive interval.</li>
<li>The <em>statistical database</em>, nominally located at
<span class="code"><em>$WEEWX_ROOT</em>/archive/stats.sdb</span>. It consists
of a separate table for each type, one record per day, keyed by the start time
of the day. </li>
</ul>
<p>The important thing to remember is that the archive database contains a record
for every archive interval and, as such, represents the c<em>urrent conditions</em>
at the time of the observation. By contrast, the statistical database represents
the <em>aggregation of conditions over a day</em>. That is, it contains the daily
minimum, maximum, and the time of the minimum and maximum, for each observation
type. As you can imagine, the statistical database is much smaller because it represents
only a summary of the data.</p>
<p>The archive database is used for both generating plot data and in template generation
(where it appears as tag <span class="code">$current</span>). The statistical database
is used only in template generation (where it appears as tags <span class="code">
$day</span>, <span class="code">$week</span>, <span class="code">$month</span>,
<span class="code">$year</span>, and <span class="code">$rainyear</span>, depending
on the aggregation time period). </p>
<h1>2. <a name="Opportunities_for_customizing_reports">Opportunities for customizing
reports</a></h1>
<p>This section discusses the two general strategies for customizing reports: by
changing options in one or more configuration file, or by changing the template
files. The former is generally easier, but occasionally the latter is necessary.</p>
<h2>Changing options</h2>
<p>Changing an option means going into either <span class="code">weewx.conf</span>
or the <span class="code">skin.conf</span> that comes with the standard distribution
and changing a value.</p>
<h3>Changing options in <span class="code">skin.conf</span></h3>
<p>With this approach, the user edits the skin configuration file for the standard
skin that comes with <span class="code">weewx</span>, located in
<span class="code"><em>$WEEWX_ROOT</em>/skins/Standard/skin.conf</span>, using a
text editor. For example, suppose you wish to use metric units in the presentation
layer. Then, you would edit section <span class="code">[Units][[Groups]]</span>
to read:</p>
<pre>[Units]</pre>
<pre> [[Groups]]</pre>
<pre class="highlight"> group_altitude = meter</pre>
<pre class="highlight"> group_degree_day = degree_C_day </pre>
<pre> group_direction = degree_compass</pre>
<pre> group_moisture = centibar</pre>
<pre> group_percent = percent</pre>
<pre class="highlight"> group_pressure = mbar</pre>
<pre> group_radiation = watt_per_meter_squared</pre>
<pre class="highlight"> group_rain = mm</pre>
<pre class="highlight"> group_rainrate = mm_per_hour</pre>
<pre class="highlight"> group_speed = meter_per_second</pre>
<pre class="highlight"> group_speed2 = meter_per_second2</pre>
<pre class="highlight"> group_temperature = degree_C</pre>
<pre> group_volt = volt</pre>
<p>The options that were changed have been <span class="highlight">highlighted</span>.
Details of the various unit options are given in <em><a href="#Units">Appendix B:
Units</a></em>.</p>
<p>Other options are available, such as changing the text label for various observation
types. Suppose your weather instrument console is actually located in a barn, not
indoors, and you want the plot for the temperature at the console to be labeled
&quot;Barn Temperature,&quot; rather than the default &quot;Inside Temperature.&quot; This can be done
by changing the &quot;inTemp&quot; option located in section [Labels][[Generic]] from </p>
<pre>[Units]</pre>
<pre> [[Generic]]</pre>
<pre> inTemp = Inside Temperature</pre>
<pre> outTemp = Outside Temperature</pre>
<pre> ...</pre>
<p>so that it reads</p>
<pre>[Units]</pre>
<pre> [[Generic]]</pre>
<pre class="highlight"> inTemp = Barn Temperature</pre>
<pre> outTemp = Outside Temperature</pre>
<pre> ...</pre>
<h3>Overriding options in <span class="code">skin.conf</span> from
<span class="code">weewx.conf</span></h3>
<p>This approach is very similar, except that instead of changing the skin configuration
file directly, you override its options by editing the main configuration file,
<span class="code">weewx.conf</span>. The advantage of this approach is that you
can use the same skin to produce several different output, each with separate options.
</p>
<p>Revisiting our example, suppose you want two reports, one in US Customary, the
other in Metric. The former will go in the directory <span class="code">public_html</span>,
the latter in a subdirectory, <span class="code">public_html/metric</span>. If you
just simply modify <span class="code">skin.conf</span>, you can get one, but not
both at the same time. Alternatively, you could create a whole new skin by copying
all the files to a new skin subdirectory then editing the new <span class="code">
skin.conf</span>. The trouble with this approach is that you would then have <em>
two</em> skins you would have to maintain. If you change something, you have to
remember to change it in both places.</p>
<p>But, there&#39;s a better approach: reuse the same skin, but overriding some options.
Here&#39;s what your <span class="code">[Report]</span> section in
<span class="code">weewx.conf</span> would look like:</p>
<pre>[Reports]</pre>
<pre>#
# This section specifies what reports, using which skins, are to be generated.
#</pre>
<pre> </pre>
<pre># Where the skins reside, relative to WEEWX_ROOT:
SKIN_ROOT = skins
</pre>
<pre># Where the generated reports should go, relative to WEEWX_ROOT:
HTML_ROOT = public_html </pre>
<pre> </pre>
<pre> # This report will use US Customary Units</pre>
<pre class="highlight"> [[USReport]]</pre>
<pre> # It&#39;s based on the Standard skin
skin = Standard</pre>
<pre> </pre>
<pre class="highlight"> # This report will use metric units:
[[MetricReport]]
# It&#39;s also based on the Standard skin:
skin = Standard
# However, override where the results will go and put them in a subdirectory:
HTML_ROOT = public_html/metric
# And override the options that were not in metric units
[[[Units]]]
[[[[Groups]]]]
group_altitude = meter
group_pressure = mbar
group_rain = mm
group_rainrate = mm_per_hour
group_speed = meter_per_second
group_speed2 = meter_per_second2
group_temperature = degree_C</pre>
<pre> </pre>
<pre> [[FTP]]</pre>
<pre> ...</pre>
<pre> ... (as before) </pre>
<p>We have done two things different from the stock reports. First (1), we&#39;ve renamed
the first report from <span class="code">StandardReport </span>to
<span class="code">USReport </span>for clarity; and (2) we&#39;ve introduced a new report
<span class="code">MetricReport</span>, just like the first, except it puts its
results in a different spot and uses different units. Both use the same skin, the
<span class="code">Standard </span>skin.</p>
<h2><a name="Customizing_templates">Customizing templates</a></h2>
<p>If you cannot achieve the results you need by changing a configuration option,
you may have to modify the templates that come with <span class="code">weewx</span>,
or write your own. </p>
<p>Template generation is done using the
<a href="http://www.cheetahtemplate.org/">Cheetah</a> templating engine. This is
a very powerful engine, which essentially lets you have the full semantics of Python
available in your templates. As this would make the templates incomprehensible to
anyone but a Python programmer, <span class="code">weewx</span> adopts a very small
subset of its power. </p>
<p>The key construct is a &#39;dot&#39; code, specifying what value you want. For example:</p>
<pre>$month.outTemp.max
$month.outTemp.maxtime
$current.outTemp</pre>
<p>would code the max outside temperature for the month, the time it occurred, and
the current outside temperature, respectively. So, an HTML file that looks like</p>
<pre>&lt;html&gt;
&lt;head&gt;
&lt;title&gt;Current conditions&lt;/title&gt;
&lt;/head&gt;
&lt;body&gt;
&lt;p&gt;Current temperature = $current.outTemp&lt;/p&gt;
&lt;p&gt;Max for the month is $month.outTemp.max, which occurred at $month.outTemp.maxtime&lt;/p&gt;
&lt;/body&gt;
&lt;/html&gt;</pre>
<p>would be all you need for a very simple HTML page that would display the text
(assuming that the unit group for temperature is <span class="code">degree_F</span>):
</p>
<p class="Example_output">Current temperature = 51.0°F<br />
Max for the month is 68.8°F, which occurred at 07-Oct-2009 15:15</p>
<p>The format that was used to format the temperature (<span class="code">51.0</span>)
is specified in section <span class="code"><a href="#Units_StringFormats">[Units][[StringFormat]]</a></span>.
The unit label <span class="code">°F</span> is from section <span class="code">
<a href="#[[Labels]]">[Units][[Labels]]</a></span>, while the time format is from
<span class="code"><a href="#TimeFormats">[Labels][[Time]]</a></span>.</p>
<h3>The dot code</h3>
<p>As we saw above, the dot codes can be very simple:</p>
<pre>## Output max outside temperature using an appropriate format and label:
$month.outTemp.max</pre>
<p>Most of the time, this is all you will be using. However, <span class="code">
weewx</span> offers extensive customization of the generate output for specialized
applications such as XML RSS feeds, or ridgidly formatted reports (such as the NOAA
reports). This section specifies the various options available.</p>
<p>There are two different versions, depending on whether the data is &quot;current&quot;,
or an aggregation over time. However, both versions are very similar</p>
<h4>Time period <span class="code">$current</span></h4>
<p>Time period <span class="code">$current</span> represents a <em>current observation</em>.
An example would be the current barometric pressure:</p>
<pre>$current.barometer</pre>
<p>The dot code for a current observation looks like:</p>
<pre><em>$current.obstype[.optional_formatting][.optional_unit_conversion]</em></pre>
<p>Where:</p>
<p class="indent"><span class="code"><em>obstype</em></span> is an observation type.
See <em><a href="#Archive_types">Appendix A, Archive Types</a></em> for a table
of observation types valid for <span class="code">current.</span></p>
<p class="indent"><span class="code"><em>optional_formatting</em></span> is an optional
formatting tag that controls how the value will appear. See the section <em>
<a href="#Formatting_options">Formatting Options</a></em> below.</p>
<p class="indent"><span class="code">optional_unit_conversion</span> is an
optional unit conversion tag. If provided, the results will be converted into
the specified units. See the section <em><a href="#Unit_conversion_options">Unit
Conversion Options</a></em> below.</p>
<h4>Aggregation periods <span class="code">$day</span>, <span class="code">$week</span>,
<span class="code">$month</span>, <span class="code">$year</span>,
<span class="code">$rainyear</span></h4>
<p>The other time periods represent an <em>aggregation over time</em>. In addition
to the time period over which the aggregation will occur, they also require an
<em>aggregation type</em>. An example would be the week&#39;s total precipitation (where
the aggregation type is <span class="code"><em>sum</em></span>):</p>
<pre>$week.rain.sum</pre>
<p>The dot code for an aggregation over time looks like:</p>
<pre><em>$period.statstype.aggregation.[optional_formatting][.optional_unit_conversion]</em></pre>
<p>Where:</p>
<p class="indent"><span class="code"><em>period</em></span> is the time period over
which the aggregation is to be done. Possible choices are <span class="code">day</span>,
<span class="code">week</span>, <span class="code">month</span>,
<span class="code">year</span>, <span class="code">rainyear</span>.</p>
<p class="indent"><span class="code"><em>statstype</em></span> is a statistical
type. See <em><a href="#Statistical_types">Appendix C, Statistical Types</a></em>,
for a table of statistical types.</p>
<p class="indent"><span class="code"><em>aggregation</em></span> is an aggregation
type. This is something like &#39;<span class="code">min</span>&#39;, &#39;<span class="code">sum</span>&#39;,
&#39;<span class="code">mintime</span>&#39;. If you ask for <span class="code">$month.outTemp.avg</span>
you are asking for the <em>average</em> outside temperature for the month. The table
<em><a href="#Statistical_types">Appendix C: Statistical types</a></em> shows what
aggregation types are available for which types.</p>
<p class="indent"><span class="code"><em>optional_formatting</em></span> is an optional
formatting tag that controls how the value will appear. See the section <em>
<a href="#Formatting_options">Formatting Options</a></em> below.</p>
<p class="indent"><span class="code">optional_unit_conversion</span> is an
optional unit conversion tag. If provided, the results will be converted into
the specified units. See the section <em><a href="#Unit_conversion_options">Unit
Conversion Options</a></em> below.</p>
<h4><a name="Formatting_options">Formatting options</a></h4>
<p>The tag <span class="code"><em>optional_formatting</em></span> can be used with
either current observations or aggregations. It can be one of:</p>
<table align="center" style="width: 80%">
<tr>
<td>
<p><strong>Optional formatting tag</strong></p>
</td>
<td>
<p><strong>Comment</strong></p>
</td>
</tr>
<tr>
<td>
<p><em>(no tag)</em></p>
</td>
<td>
<p>Value is returned as a string, formatted using an appropriate string
format from <span class="code">skin.conf</span>. A unit label from
<span class="code">skin.conf </span>is also attached at the end.</p>
</td>
</tr>
<tr>
<td><span class="code">.string(<em>NONE_string</em></span>)</td>
<td>Value is returned as a string, formatted using an appropriate string
format from <span class="code">skin.conf</span>. If the value is
<span class="code">None</span>, the string <span class="code">NONE_string</span>
will be substituted if given, otherwise the value for <span class="code">
NONE</span> in <span class="code"><a href="#Units_StringFormats">[Units][[Formats]]</a></span>
will be used. A unit label from <span class="code">skin.conf</span> will
be attached at the end.</td>
</tr>
<tr>
<td><span class="code">.formatted</span></td>
<td>Value is returned as a string, formatted using an appropriate string
format and <span class="code">None</span> value from <span class="code">
skin.conf</span>. No label.</td>
</tr>
<tr>
<td><span class="code">.format(<em>string_format</em>, <em>NONE_string</em>)</span></td>
<td>Value is returned as a string, using the string format specified with
<em>string_format</em>. If the value is <span class="code">None</span>,
the string <span class="code">NONE_string</span> will be substituted if
given, otherwise the value for <span class="code">NONE</span> in
<span class="code"><a href="#Units_StringFormats">[Units][[Formats]]</a></span>
will be used. A unit label from <span class="code">skin.conf</span> will
be attached at the end.</td>
</tr>
<tr>
<td class="code">.nolabel(string_format, NONE_string)</td>
<td>Value is returned as a string, using the string format specified with
<em>string_format</em>. If the value is <span class="code">None</span>,
the string <span class="code">NONE_string</span> will be substituted if
given, otherwise the value for <span class="code">NONE</span> in
<span class="code"><a href="#Units_StringFormats">[Units][[Formats]]</a></span>
will be used. No label will be attached at the end.</td>
</tr>
<tr>
<td>
<p><span class="code">.raw</span></p>
</td>
<td>Value is returned &quot;as is&quot; without being converted to a string and without
any formatting applied. You must be prepared to deal with a
<span class="code">None</span> value unless the value is converted directly
to a string. In this case, it will be converted to the empty string (<span class="code">&#39;&#39;</span>)</td>
</tr>
</table>
<p>Summary:</p>
<table align="center" style="width: 80%">
<tr>
<td><strong>Formatting tag</strong></td>
<td><strong>Format used</strong></td>
<td><strong>Label Used</strong></td>
<td><strong>NONE string</strong></td>
<td><strong>Returned value</strong></td>
</tr>
<tr>
<td><em>(no tag)</em></td>
<td>From <span class="code">skin.conf</span></td>
<td>From <span class="code">skin.conf</span></td>
<td>From <span class="code">skin.conf</span></td>
<td>string</td>
</tr>
<tr>
<td class="code">.string</td>
<td>From <span class="code">skin.conf</span></td>
<td>From <span class="code">skin.conf</span></td>
<td>Optional user-supplied</td>
<td>string</td>
</tr>
<tr>
<td class="code">.formatted</td>
<td>From <span class="code">skin.conf</span></td>
<td>No label</td>
<td>From <span class="code">skin.conf</span></td>
<td>string</td>
</tr>
<tr>
<td class="code">.format</td>
<td>User-supplied</td>
<td>From <span class="code">skin.conf</span></td>
<td>Optional user-supplied</td>
<td>string</td>
</tr>
<tr>
<td class="code">.nolabel</td>
<td>User-supplied</td>
<td>No label</td>
<td>Optional user-supplied</td>
<td>string</td>
</tr>
<tr>
<td class="code">.raw</td>
<td>None</td>
<td>No label</td>
<td>None</td>
<td>native value</td>
</tr>
</table>
<p>Here are some examples with the expected results:</p>
<table align="center">
<tr>
<td><strong>Tag</strong></td>
<td><strong>Result</strong></td>
<td><strong>Comment</strong></td>
</tr>
<tr>
<td class="code">$current.outTemp </td>
<td class="code">45.2°F </td>
<td>String formatting and label from <span class="code">skin.conf</span></td>
</tr>
<tr>
<td class="code">$current.outTemp.string</td>
<td class="code">45.2°F</td>
<td>String formatting and label from <span class="code">skin.conf</span></td>
</tr>
<tr>
<td class="code">$current.UV.string</td>
<td class="code">N/A</td>
<td>This example assumes that the instrument has no UV sensor, resulting
in a <span class="code">None</span> value. The string specified by
<span class="code">NONE</span> in <span class="code">
<a href="#Units_StringFormats">[Units][[Formats]]</a></span> is substituted.</td>
</tr>
<tr>
<td class="code">$current.UV.string(&quot;No UV&quot;)</td>
<td class="code">No UV</td>
<td>This example assumes that the instrument has no UV sensor, resulting
in a <span class="code">None</span> value. The string supplied by the user
is substituted.</td>
</tr>
<tr>
<td class="code">$current.outTemp.formatted </td>
<td class="code">45.2</td>
<td>String formatting from <span class="code">skin.conf</span>; no label</td>
</tr>
<tr>
<td class="code">$current.outTemp.format(&quot;%.3f&quot;) </td>
<td class="code">45.200°F</td>
<td>Specified string format used; label from <span class="code">skin.conf</span>.</td>
</tr>
<tr>
<td class="code">$current.dateTime</td>
<td class="code">02-Apr-2010 16:25</td>
<td>Time formatting and label from <span class="code">skin.conf</span></td>
</tr>
<tr>
<td class="code">$current.dateTime.format(&quot;%H:%M&quot;)</td>
<td class="code">16:25</td>
<td>Specified time format used; label from <span class="code">skin.conf</span>.</td>
</tr>
<tr>
<td class="code">$current.dateTime.raw</td>
<td class="code">1270250700</td>
<td>Unix epoch time, converted to string by template engine.</td>
</tr>
<tr>
<td class="code">$current.outTemp.raw</td>
<td class="code">45.2</td>
<td>Float returned, converted to string by template engine.</td>
</tr>
<tr>
<td class="code">$month.dateTime</td>
<td class="code">01-Apr-2010 00:00</td>
<td>Time formatting and label from <span class="code">skin.conf</span></td>
</tr>
<tr>
<td class="code">$month.outTemp.avg </td>
<td class="code">40.8°F</td>
<td>String formatting and label from <span class="code">skin.conf</span></td>
</tr>
<tr>
<td class="code">$month.outTemp.avg.string</td>
<td class="code">40.8°F</td>
<td>Time formatting and label from <span class="code">skin.conf</span></td>
</tr>
<tr>
<td class="code">$month.UV.avg.string</td>
<td class="code">N/A</td>
<td>This example assumes that the instrument has no UV sensor, resulting
in a <span class="code">None</span> value. The string specified by
<span class="code">NONE</span> in <span class="code">
<a href="#Units_StringFormats">[Units][[Formats]]</a></span> is substituted.</td>
</tr>
<tr>
<td class="code">$month.UV.avg.string(&quot;No UV&quot;)</td>
<td class="code">No UV</td>
<td>This example assumes that the instrument has no UV sensor, resulting
in a <span class="code">None</span> value. The string supplied by the user
is substituted.</td>
</tr>
<tr>
<td class="code">$month.outTemp.avg.formatted </td>
<td class="code">40.8</td>
<td>String formatting from <span class="code">skin.conf</span>; no label</td>
</tr>
<tr>
<td class="code">$month.outTemp.avg.format(&quot;%.3f&quot;)</td>
<td class="code">40.759°F</td>
<td>Specified string format used; no label</td>
</tr>
<tr>
<td class="code">$month.outTemp.avg.raw </td>
<td class="code">40.7589690722</td>
<td>Float returned, converted to string by template engine</td>
</tr>
<tr>
<td class="code">$month.UV.avg.raw</td>
<td class="code"><em>(empty)</em></td>
<td><span class="code">None</span> value converted to empty string by template
engine.</td>
</tr>
</table>
<p>Note:</p>
<ul>
<li>Tags that take an argument (such as <span class="code">.string(NONE_string)</span>)
do not require parenthesis if the argument is omitted.Thus, you can specify
either <span class="code">$month.outTemp.string()</span> or
<span class="code">$month.outTemp.string</span>, if you want the default value
of <span class="code">NONE_string</span>. They produce the same results.</li>
</ul>
<h4><a name="Unit_conversion_options">Unit conversion options</a></h4>
<p>The tag <span class="code"><em>optional_unit_conversion</em></span> can be
used with either current observations or aggregations. If supplied, the results
will be converted to the specified units. For example, if you have set
<span class="code">group_pressure</span> to inches of mercury (<span class="code">inHg</span>),
then the tag</p>
<p class="tty">Today&#39;s average pressure=$day.barometer.avg</p>
<p>would normally give a result such as</p>
<p class="Example_output">Today&#39;s average pressure=30.05 inHg</p>
<p>However, if you add &quot;mbar&quot; to the end, </p>
<p class="tty">$day.barometer.avg.mbar</p>
<p>then the results will be in millibars:</p>
<p class="Example_output">Today&#39;s average pressure=1017.5 mbar</p>
<p>If an inappropriate conversion is asked for, <em>e.g.</em>,</p>
<p class="tty">Today&#39;s average pressure=$day.barometer.degree_C</p>
<p>then the offending tag will be put in the output:</p>
<p class="Example_output">Today&#39;s average pressure=$day.barometer.degree_C</p>
<p>&nbsp;</p>
<h3><a name="Type_dateTime">Type <span class="code">dateTime</span></a></h3>
<p>While not an observation type, in many ways the time of an observation,
<span class="code">dateTime</span>, can be treated as one. A tag such as
<span class="code">$current.dateTime</span> represents the <em>current time</em>
(more properly, the time as of the end of the last archive interval), a tag such
as <span class="code">$month.dateTime</span> represents the start time of the month.
Like true observation types, explicit formats can be specified, except that they
require a
<a href="http://docs.python.org/library/datetime.html#strftime-strptime-behavior">strftime()
<em>time format</em></a>, rather than a <em>string format:</em></p>
<pre>$month.dateTime.format(&quot;%B %Y)</pre>
<p>produces</p>
<pre>January 2010</pre>
<p>The returned string value will always be in <em>local time</em>. </p>
<p>The raw value of <span class="code">dateTime</span> is Unix Epoch Time (number
of seconds since 00:00:00 UTC 1 Jan 1970, <em>i.e.</em>, a large number), which
you must convert yourself to local time. It is guaranteed to never be
<span class="code">None</span>, so you don&#39;t worry have to worry about handling
a <span class="code">None</span> value. </p>
<p>&nbsp;</p>
<h3>Unit tags</h3>
<p>The unit type, label, and string formats are also available, allowing you to
do highly customized labels:</p>
<table align="center" style="width: 40%">
<tr>
<td><strong>Tag</strong></td>
<td><strong>Results</strong></td>
</tr>
<tr>
<td class="code">$unit.unit_type.outTemp</td>
<td class="code">degree_C</td>
</tr>
<tr>
<td class="code">$unit.label.outTemp</td>
<td class="code">°C</td>
</tr>
<tr>
<td class="code">$unit.format.outTemp</td>
<td class="code">%.1f</td>
</tr>
</table>
<p>As a summary, the tag</p>
<pre>$day.outTemp.max.formatted$unit.label.outTemp</pre>
<p>would result in</p>
<pre>21.2°C</pre>
<p>(assuming metric values have been specified for <span class="code">group_temperature</span>),
essentially reproducing the results of the simpler tag <span class="code">$day.outTemp.max</span>.</p>
<h3>Iteration</h3>
<p>For dot codes using an aggregation (<em>e.g.</em>, <span class="code">$day</span>,
<span class="code">$week</span>, <span class="code">$month</span>,
<span class="code">$year</span>, <span class="code">$rainyear</span>, then the aggregation
period can be iterated over by day or month. These are the only two iteration periods
available in Version 1.7. </p>
<p>This example uses a Cheetah &#39;<span class="code">for</span>&#39; loop to iterate over
all months in a year, printing out each month&#39;s min and max temperature (the iteration
loop is highlighted):</p>
<pre>&lt;html&gt;</pre>
<pre> &lt;head&gt;</pre>
<pre> &lt;title&gt;Year stats by month&lt;/title&gt;</pre>
<pre> &lt;/head&gt;</pre>
<pre> &lt;body&gt;</pre>
<pre> &lt;p&gt;Min, max temperatures by month:&lt;/p&gt;</pre>
<pre class="highlight"> #for $month in $year.months</pre>
<pre> &lt;p&gt;$month.dateTime.format(&quot;%B&quot;): Min, max temperatures: $month.outTemp.min $month.outTemp.max&lt;/p&gt;</pre>
<pre class="highlight"> #end for </pre>
<pre> &lt;/body&gt;</pre>
<pre>&lt;/html&gt;</pre>
<p>Produces results:</p>
<pre>Min, max temperatures by month:
January: Min, max temperatures: 30.1°F 51.5°F
February: Min, max temperatures: 24.4°F 58.6°F
March: Min, max temperatures: 27.3°F 64.1°F
April: Min, max temperatures: 33.2°F 52.5°F
May: Min, max temperatures: N/A N/A
June: Min, max temperatures: N/A N/A
July: Min, max temperatures: N/A N/A
August: Min, max temperatures: N/A N/A
September: Min, max temperatures: N/A N/A
October: Min, max temperatures: N/A N/A
November: Min, max temperatures: N/A N/A
December: Min, max temperatures: N/A N/A
</pre>
<p>See the NOAA template files <span class="code">NOAA/NOAA-YYYY.txt.tmpl</span>
and <span class="code">NOAA/NOAA-YYYY-MM.txt.tmpl</span> for examples using iteration,
as well as explicit formatting.</p>
<h2>Writing a custom generator</h2>
<p>To do more sophisticated customization it may be necessary to extend an existing
generator, or write your own. </p>
<h4>Extending an existing generator</h4>
<p>In the section on <em><a href="#Customizing_templates">Customizing templates</a></em>,
we have seen how you can change a template and make use of the various tags available
such as <span class="code">$day.outTemp.max</span> for the maximum outside temperature
for the day. But, what if you want to introduce some new data for which no tag is
available? </p>
<p>If you wish to introduce a static tag, that is, one that will not change with
time (such as a Google analytics Tracker ID or your name), then this is very easy:
simply put it in section <span class="code"><a href="#[Extras]">[Extras]</a></span>
in the skin configuration file. More information on how to do this can be found
there.</p>
<p>But, what if you wish to introduce a more dynamic tag, one that requires some
calculation? Simply putting it in the <span class="code">[Extras]</span> section
won&#39;t do, because then it cannot change. </p>
<p>The answer is to extend the default file generator<span class="code"> weewx.filegenerator.FileGenerator</span>
by subclassing, then override the function that returns the <em>search list</em>.
The search list is a list of dictionaries that the template engine searches through,
trying all keys in each dictionary, looking for a match for your tag. For example,
for the &quot;ToDate&quot; generator, you would override function <span class="code">getToDateSearchList()</span>,
and add a small dictionary with your tag as the key to the list returned by the
superclass.</p>
<p>Let&#39;s look at an example. The stock <span class="code">weewx</span> reports offers
statistical summaries by day, week, month, and year. Suppose we would like to add
one more: all-time statistics. This would allow us to display statistics such as
the all-time high or low temperature seen at your station. </p>
<p>This example is included in the distribution as <span class="code">examples/mygenerator.py</span>:</p>
<pre>from weewx.filegenerator import FileGenerator
from weewx.stats import TimeSpanStats
from weeutil.weeutil import TimeSpan
class MyFileGenerator(FileGenerator): # 1
def getToDateSearchList(self, currentRec, stop_ts): # 2
# Get a TimeSpan object that represents all time up to the stop time:
all_time = TimeSpan(self.start_ts, stop_ts) # 3
# Get a TimeSpanStats object :
all_stats = TimeSpanStats(self.statsdb,
all_time,
unit_info=self.unit_info) # 4
# Get the superclass&#39;s search list:
search_list = FileGenerator.getToDateSearchList(self, currentRec, stop_ts) #5
# Now tack on my addition as a small dictionary with key &#39;alltime&#39;:
search_list += [ {&#39;alltime&#39; : all_stats} ] # 6
return search_list
</pre>
<p>Going through the example, line by line:</p>
<ol>
<li>Subclass from class <span class="code">FileGenerator</span>. The new class
will be caled <span class="code">MyFileGenerator</span></li>
<li>Override member function <span class="code">getToDateSearchList()</span>.
The parameters are <span class="code">self</span> (Python&#39;s way of indicating
the instance we are working with), <span class="code">currentRec</span> (a dictionary
with the current conditions), and <span class="code">stop_ts</span> (the ending
time for the &quot;to date&quot; summary, in Unix epoch time).</li>
<li>Attribute <span class="code">self.start_ts</span> is available as the earliest
time seen in the main archive database. The class <span class="code">TimeSpan</span>
is a utility class that represents an interval of time. Here, we are creating
an instance of <span class="code">TimeSpan</span> that represents all time preceeding
<span class="code">stop_ts</span>.</li>
<li>Class <span class="code">TimeSpanStats</span> represents a statistical calculation
over a time period. It takes 3 parameters. The first, <span class="code">self.statsdb</span>
is the statistical database the calculation is to be run against; the second
is the timespan over which the calculation is to be done; and the third,
<span class="code">self.unit_info</span>, is an instance of class
<span class="code">weewx.units.UnitInfo</span>, which contains information about
the target units the results are to be returned in as well as formatting and
labeling information. </li>
<li>Get the search list from the superclass.</li>
<li>Tack on our addition and return the results. The search list will now consist
of a list of dictionaries, including a small one we added on the end that has
a single key, &#39;<span class="code">alltime</span>&#39;, with value an instance of
<span class="code">TimeSpanStats</span>.</li>
</ol>
<p>With this approach, you can now include &quot;all time&quot; statistics in your HTML templates:</p>
<pre>...
...
&lt;table&gt;
&lt;tr&gt;
&lt;td&gt;Maximum temperature to date: &lt;/td&gt;
&lt;td&gt;$alltime.outTemp.max&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;
&lt;td&gt;Minimum temperature to date: &lt;/td&gt;
&lt;td&gt;$alltime.outTemp.min
&lt;/tr&gt;
... (more table entries)</pre>
<pre class="tty"> </pre>
<p>One additonal step is required: to tell the report service to run your generator
instead of the default generator. Modify option <span class="code">[Generators]generator_list</span>
in the skin configuration file <span class="code">skin.conf</span> to read:</p>
<pre>generator_list = examples.mygenerator.MyFileGenerator, weewx.imagegenerator.ImageGenerator, weewx.reportengine.CopyGenerator</pre>
<p>NB: If you create a custom generator some place other than where
<span class="code">weewxd.py</span> resides, you may have to specify its location
in the environment variable <span class="code">PYTHON_PATH</span>:</p>
<pre>export PYTHON_PATH=/home/me/secret_location</pre>
<h1>3. <a name="Reference:_The_Standard_skin_configuration_file">Reference: The
Standard skin configuration file</a></h1>
<p>This section is a reference to the options appearing in the Standard skin configuration
file, found in <span class="code"><em>$WEEWX_ROOT</em>/skins/Standard/skin.conf</span>.</p>
<p>It is worth noting that, like the main configuration file <span class="code">
weewx.conf</span>, UTF-8 is used throughout. The most important options are up near
the top of the file.&nbsp; The truly important ones, the ones you are likely to
have to customize for your station, are shown in <span class="bold_n_blue">
<strong>bold face and in blue</strong></span>. </p>
<h2 class="config_section"><a name="[Extras]">[Extras]</a></h2>
<p>This section is available to you to add any static tags that you might want to
be available in the templates. As an example, the stock <span class="code">skin.conf</span>
file includes two options: <span class="code">radar_url</span>, which is available
as tag <span class="code">$Extras.radar_url</span>, and <span class="code">googleAnalyticsId</span>,
available as tag <span class="code">$Extras.googleAnalyticsId</span>. If you take
a look at the template <span class="code">index.html.tmpl</span> you will see examples
of testing for these tags (search the file for the string &#39;<span class="code">radar_url</span>&#39;
or <span class="code">googleAnalyticsId</span> to find them).</p>
<p class="config_option">radar_url</p>
<p>If set, the NOAA radar image will be displayed. If commented out, no image will
be displayed.</p>
<p class="config_option">googleAnalyticsId</p>
<p>If you have a <a href="http://www.google.com/analytics/">Google Analytics ID</a>,
you can set it here. The Google Analytics Javascript code will then be included,
enabling analytics of your website usage. If commented out, the code will not be
included.</p>
<h4>Extending <span class="code">[Extras]</span></h4>
<p>Other tags can be added in a similar manner, including subsections. For example,
say you have added a video camera and you would like to add a still image with a
hyperlink to a page with the video. You want all of these options to be neatly contained
in a subsection. </p>
<pre>[Extras]
[[video]]
still = video_capture.jpg
hyperlink = <a href="http://www.eatatjoes.com/video.html">http://www.eatatjoes.com/video.html</a></pre>
<p>Then in your template you could refer to these as:</p>
<pre>&lt;a href=&quot;$Extras.video.hyperlink&quot;&gt;
&lt;img src=&quot;$Extras.video.still&quot; alt=&quot;Video capture&quot;/&gt;
&lt;/a&gt;</pre>
<h2 class="config_section">[Units]</h2>
<p>This section deals with Units and their formatting. </p>
<h3 class="config_section">[[Groups]]</h3>
<p>This subsection lists all the <em>Unit Groups</em> and specifies which unit system
is to be used for each one of them. </p>
<p>As there are many different observational measurement types (such as &#39;<span class="code">outTemp</span>&#39;,
&#39;<span class="code">barometer</span>&#39;, etc.) used in <span class="code">weewx</span>
(more than 50 at last count), it would be tedious, not to say possibly inconsistent,
to specify a different measurement system for each one of them. At the other extreme,
requiring all of them to be &quot;U.S. Customary&quot; or &quot;Metric&quot; seems overly restrictive.
<span class="code">Weewx</span> has taken a middle route and divided all the different
observation types into 12 different &quot;<em>unit groups</em>.&quot; A unit group is something
like &quot;<span class="code">group_temperature</span>.&quot; It represents the measurement
system to be used by all observation types that are measured in temperature, such
as inside temperature (type &#39;<span class="code">inTemp</span>&#39;), outside temperature
(&#39;<span class="code">outTemp</span>&#39;), dewpoint (&#39;<span class="code">dewpoint</span>&#39;),
wind chill (&#39;<span class="code">windchill</span>&#39;), and so on. If you decide that
you want unit group <span class="code">group_temperature</span> to be measured in
&quot;<span class="code">degree_C</span>&quot; then you are saying <em>all</em> members of
its group will be reported in degrees Celsius.</p>
<p>Note that the unit system is always specified in the singular. That is, specify
&quot;<span class="code">degree_C</span>&quot; or &quot;<span class="code">foot</span>&quot;, not &quot;<span class="code">degrees_C</span>&quot;
or &quot;<span class="code">feet</span>&quot;. See the Appendix <em><a href="#Units">Units</a></em>
for more information, including a concise summary of the groups, their members,
and which options can be used for each group.</p>
<p class="config_important"><a class="config_option" name="group_altitude">group_altitude</a></p>
<p>Which measurement unit to be used for altitude. Possible options are &#39;<span class="code">foot</span>&#39;
or &#39;<span class="code">meter</span>&#39;.</p>
<p class="config_option">group_direction</p>
<p>Which measurement unit to be used for direction. The only option is &quot;<span class="code">degree_compass</span>&quot;.</p>
<p class="config_option">group_moisture</p>
<p>The measurement unit to be used for soil moisture. The only option is &quot;<span class="code">centibar</span>.&quot;</p>
<p class="config_option">group_percent</p>
<p>The measurement unit to be used for percentages. The only option is &quot;<span class="code">percent</span>&quot;.</p>
<p class="config_important">group_pressure</p>
<p>The measurement unit to be used for pressure. Possible options are one of &quot;<span class="code">inHg</span>&quot;
(inches of mercury), &quot;<span class="code">mbar</span>&quot;, or &quot;<span class="code">hPa</span>.&quot;</p>
<p class="config_option">group_radiation</p>
<p>The measurement unit to be used for radiation. The only option is &quot;<span class="code">watt_per_meter_squared</span>.&quot;</p>
<p class="config_important">group_rain</p>
<p>The measurement unit to be used for precipitation. Options are &quot;<span class="code">inch</span>&quot;,
&quot;<span class="code">cm</span>,&quot; or &quot;<span class="code">mm</span>.&quot;</p>
<p class="config_important">group_rainrate</p>
<p>The measurement unit to be used for rate of precipitation. Possible options are
one of &quot;<span class="code">inch_per_hour</span>&quot;, &quot;<span class="code">cm_per_hour</span>&quot;,
or &quot;<span class="code">mm_per_hour</span>&quot;.</p>
<p class="config_important">group_speed</p>
<p>The measurement unit to be used for wind speeds. Possible options are one of
&quot;<span class="code">mile_per_hour</span>&quot;, &quot;<span class="code">km_per_hour</span>&quot;,
&quot;<span class="code">knot</span>&quot;, or &quot;<span class="code">meter_per_second</span>.&quot;</p>
<p class="config_important">group_speed2</p>
<p>This group is similar to <span class="code">group_speed</span>, but is used for
calculated wind speeds which typically have a slightly higher resolution. Possible
options are one &quot;<span class="code">mile_per_hour2</span>&quot;, &quot;<span class="code">km_per_hour2</span>&quot;,
&quot;<span class="code">knot2</span>&quot;, or &quot;<span class="code">meter_per_second2</span>&quot;.</p>
<p><a class="config_important" name="group_temperature">group_temperature</a></p>
<p>The measurement unit to be used for temperatures. Options are &quot;<span class="code">degree_F</span>&quot;
or &quot;<span class="code">degree_C</span>.&quot;</p>
<p class="config_option">group_volt</p>
<p>The measurement unit to be used for voltages. The only option is &quot;<span class="code">volt</span>.&quot;</p>
<h3 class="config_section"><a name="Units_StringFormats">[[StringFormats]]</a></h3>
<p>This sub-section is used to specify what string format is to be used for each
unit when a quantity needs to be converted to a string. Typically, this happens
with y-axis labeling on plots and for statistics in HTML file generation. For example,
the options</p>
<pre>degree_C = %.1f
inch = %.2f</pre>
<p>would specify that the given string formats are to be used when formatting any
temperature measured in degrees Celsius or any precipitation amount measured in
inches, respectively. The
<a href="http://docs.python.org/library/string.html#format-specification-mini-language">
formatting codes are those used by Python</a>, a, and are very similar to C&#39;s
<span class="code">sprintf()</span> codes.</p>
<p>You can also specify what string to use for an invalid or unavailable measurement
(value &#39;<span class="code">None</span>&#39;). For example,</p>
<pre>NONE = &quot; N/A &quot;</pre>
<h3 class="config_section"><a name="[[Labels]]">[[Labels]]</a></h3>
<p>This subsection specifies what label is to be used for each measurement unit
type. For example, the options</p>
<pre>degree_F = °F
inch = &#39; in&#39;</pre>
<p>would cause all temperatures to have unit labels &#39;<span class="code">°F</span>&#39;
and all precipitation to have labels&nbsp; &#39;<span class="code"> in</span>&#39;. If any
special symbols are to be used (such as the degree sign above) they should be encoded
in UTF-8. This is generally what most text editors use if you cut-and-paste from
a character map. Labels used in plot images will be converted to Latin-1 first (this
is all the Python Imaging Library can handle).</p>
<h3 class="config_section"><a name="TimeFormats">[[TimeFormats]]</a></h3>
<p>This sub-section is used for time labels. It uses
<a href="http://docs.python.org/library/datetime.html#strftime-behavior">strftime()</a>
formats. For example</p>
<pre>week = %H:%M on %A
month = %d-%b-%Y %H:%M</pre>
<p>would specify that week data should use a format such as &quot;<span class="code">15:20
on Sunday</span>&quot;, while month data should look like &quot;<span class="code">06-Oct-2009
15:20</span>&quot;</p>
<h3 class="config_section">[[DegreeDays]] </h3>
<p class="config_important">heating_base<br />
cooling_base</p>
<p>Set to the base temperature for calculating heating and cooling degree-days,
along with the unit to be used:</p>
<pre>heating_base = 65.0, degree_F
cooling_base = 65.0, degree_C</pre>
<h2 class="config_section">[Labels]</h2>
<p>This section sets the various labels to use.</p>
<p class="config_option">hemispheres </p>
<p>Comma separated list for the labels to be used for the four hemispheres. The
default is &quot;<span class="code">N, S, E, W</span>&quot;.</p>
<h3 class="config_section">[[Generic]]</h3>
<p>This sub-sections specifies default labels to be used for each SQL type. For
example, options</p>
<pre>inTemp = Temperature inside the house
outTemp = Outside Temperature</pre>
<p>would cause the given labels to be used for plots involving SQL types
<span class="code">inTemp </span>and <span class="code">outTemp</span>.</p>
<h2 class="config_section">[Almanac]</h2>
<p>This section controls what text to use for the almanac. It consists of only one
entry</p>
<p class="config_option">moon_phases</p>
<p>This option is a comma separated list of labels to be used for the eight phases
of the moon. Default is &quot;<span class="code">New, Waxing crescent, First quarter,
Waxing gibbous, Full, Waning gibbous, Last quarter, Waning crescent</span>&quot;.</p>
<h2 class="config_section">[FileGenerator]</h2>
<p>This section is used by generator <span class="code">weewx.reportengine.FileGenerator</span>
and controls text generation from templates, specifically which files are to be
produced from which template.</p>
<h3>Overview of file generation</h3>
<p>Customization of file generation consists of playing with the various options
offered below and, failing that, modifying the template files that come with the
distribution.</p>
<p>Each template file is named something like <span class="code"><em>D/F.E.tmpl</em></span>,
where <span class="code">D</span> is the subdirectory the template sits in and will
also be the subdirectory the results will be put in, and <span class="code">F.E</span>
is the generated file name. So, given a template file with name
<span class="code">Acme/index.html.tmpl</span>, the results will be put in
<span class="code"><em>$HTML_ROOT</em>/Acme/index.html</span>.</p>
<p>The skin that comes with the standard distribution of <span class="code">weewx</span>
contains three different kinds of generated output:</p>
<ol>
<li>Summary by month. In addition to the naming rules above, if the template
file has the letters <span class="code">YYYY</span> and <span class="code">MM</span>
in its name, these will be substituted for the year and month, respectively.
So, a template with the name <span class="code">summary-YYYY-MM.html.tmpl</span>
would have name <span class="code">summary-2010-03.html</span> for the month
of March, 2010. The default distribution has been set up to produce NOAA monthly
summaries, one for each month, as a simple text file (no HTML). </li>
<li>Summary by year.&nbsp; In addition to the naming rules above, if the template
file has the letters <span class="code">YYYY</span> in its name, the year will
be substituted. The default distribution has been set up to produce NOAA yearly
summaries, one for each year, as a simple text file (no HTML). </li>
<li>Summary &quot;To Date&quot;. The default distribution has been set up to produce reports
for the day, week, month, and year-to-date observations. These four files are
all HTML files. The first, the daily summary (output file i<span class="code">ndex.html</span>),
includes a drop-down list that allows the NOAA month and yearly summaries to
be displayed.</li>
</ol>
<h3>General</h3>
<p class="config_option">encoding</p>
<p>This option controls which encoding is to be used for the generated output. There
are 3 possible choices:</p>
<table align="center" style="width: 60%">
<tr>
<td><strong>Encoding</strong></td>
<td><strong>ComComments</strong></td>
</tr>
<tr>
<td class="code">html_entities</td>
<td>Non 7-bit characters will be represented as HTML entities (<em>e.g.</em>
the degree sign will be represented as <span class="code">&amp;#176;</span>)</td>
</tr>
<tr>
<td class="code">utf8</td>
<td>Non 7-bit characters will be represented in UTF-8.</td>
</tr>
<tr>
<td class="code">strict_ascii</td>
<td>Non 7-bit characters will be ignored.</td>
</tr>
</table>
<p>By default, the encoding <span class="code">html_entities</span> is used for
HTML files, <span class="code">strict_ascii</span> for the NOAA template files.
</p>
<h3 class="config_section">[[SummaryByMonth]]</h3>
<p>This section controls which summaries-by-month are generated. For each such summary,
it should have its own sub-subsection, with option <span class="code">template</span>
listing the template to be used. The default configuration generates NOAA-by-month
summaries and is summarized below as an example. Additional &quot;by month&quot; summaries
can be added easily by following the same pattern.</p>
<h4 class="config_section">[[[NOAA_month]]]</h4>
<p class="config_option">encoding</p>
<p>Set to <span class="code">strict_ascii</span> for the NOAA monthly summary.</p>
<p class="config_option">template</p>
<p>This option is set to the source template for the NOAA monthly summary,
<span class="code">NOAA/NOAA-YYYY-MM.txt.tmpl</span>.</p>
<h3 class="config_section">[[SummaryByYear]]</h3>
<p>This section controls which summaries-by-year are generated. For each such summary,
it should have its own sub-subsection, with option <span class="code">template</span>
listing the template to be used. The default configuration generates NOAA-by-year
summaries and is summarized below as an example. Additional &quot;by year&quot; summaries
can be added easily by following the pattern.</p>
<h4 class="config_section">[[[NOAA_year]]]</h4>
<p class="config_option">encoding</p>
<p>Set to <span class="code">strict_ascii</span> for the NOAA year summary.</p>
<p class="config_option">template</p>
<p>This option is set to the source template for the NOAA yearly summary,
<span class="code">NOAA/NOAA-YYYY.txt.tmpl</span>.</p>
<h3 class="config_section">[[ToDate]]</h3>
<p>This section controls which observations-to-date are generated. The default configuration
generates four files: one for day, week, month, and year. Although the sub-subsections
below have names such as &#39;week&#39; or &#39;month&#39;, this is not used in their generation.&nbsp;
Output is set by the template <em>content</em>, not the name of the sub-subsection
— the names below could as easily have been&#39;Fred&#39;, &#39;Mary&#39;, &#39;Peter&#39;, and &#39;George&#39;
and had the same output.</p>
<p>Additional observations-to-date pages can be created easily by adding a new sub-subsection
and giving it a unique name (&quot;Jill&quot;?), then giving the path to its template as option
<span class="code">template</span>. </p>
<h4 class="config_section">[[[day]]]</h4>
<p class="config_option">template</p>
<p>Set to <span class="code">index.html.tmpl</span>, which contains the template
for the day summary.</p>
<h4 class="config_section">[[[week]]]</h4>
<p class="config_option">template</p>
<p>Set to <span class="code">week.html.tmpl</span>, which contains the template
for the week summary.</p>
<h4 class="config_section">[[[month]]]</h4>
<p class="config_option">template</p>
<p>Set to <span class="code">month.html.tmpl</span>, which contains the template
for the month summary.</p>
<h4 class="config_section">[[[year]]]</h4>
<p class="config_option">template</p>
<p>Set to <span class="code">year.html.tmpl</span>, which contains the template
for the year summary.</p>
<h4 class="config_section">[[[RSS]]]</h4>
<p>Set to <span class="code">RSS/weewx_rss.xml.tmpl</span>, which contains a template
for an RSS feed.</p>
<h2 class="config_section">[CopyGenerator]</h2>
<p>This section is used by generator <span class="code">weewx.reportengine.CopyGenerator</span>
and controls which files are to be copied over from the skin subdirectory to the
destination directory. Think of it as &quot;file generation,&quot; except that rather than
going through the template engine, the files are simply copied over. </p>
<p class="config_option">copy_once</p>
<p>This option controls which files get copied over on the first invocation of the
report engine service. Typically, this is things such as style sheets or background
GIFs. Wildcards can be used.</p>
<p class="config_option">copy_always</p>
<p>This is a list of files that should be copied on every invocation. Wildcards
can be used. </p>
<h2 class="config_section">[ImageGenerator]</h2>
<p>This section is used by generator <span class="code">weewx.reportengine.ImageGenerator</span>
and controls which images (plots) get generated and with which options. While complicated,
it is extremely flexible and powerful.</p>
<h3>Time periods</h3>
<p>The section consists of one or more sub-sections, one for each time period (day,
week, month, and year). These sub-sections define the nature of aggregation and
plot types for the time period. For example, here&#39;s a typical set of options for
sub-section <span class="code">[[month_images]]</span>, controlling how images that
cover a month period are generated:</p>
<pre>[[month_images]]
x_label_format = %d
bottom_label_format = %m/%d/%y %H:%M
time_length = 2592000 # == 30 days
aggregate_type = avg
aggregate_interval = 10800 # == 3 hours</pre>
<p>The option <span class="code">x_label_format</span> gives a
<a href="http://docs.python.org/library/datetime.html#strftime-behavior">strftime()</a>
type format for the x-axis. In this example, it will only show days (format option
&quot;<span class="code">%d</span>&quot;). The <span class="code">bottom_label_format</span>
is the format used to time stamp the image at the bottom. In this example, it will
show the time as <span class="code">10/25/09 15:35</span>. A plot will cover a nominal
30 days, and all items included in it will use an aggregate type of averaging over
3 hours. </p>
<h3>Image files</h3>
<p>Within each sub-section is another nesting, one for each image to be generated.
The title of each sub-sub-section is the filename to be used for the image. Finally,
at one additional nesting level (!) are the logical names of all the line types
to be drawn in the image.&nbsp; Values specified in the level above can be overridden.
For example, here&#39;s a typical set of options for sub-sub-section
<span class="code">[[[monthrain]]]</span>:</p>
<pre>[[[monthrain]]]
plot_type = bar
yscale = None, None, 0.02
[[[[rain]]]]
aggregate_type = sum
aggregate_interval = 86400
label = Rain (daily avg)</pre>
<p>This will generate an image file with name <span class="code">monthrain.png</span>.
It will be a bar plot. Option <span class="code">yscale</span> controls the y-axis
scaling — if left out, the scale will automatically be chosen. However, in this
example we are choosing to exercise some degree of control by specifying values
explicitly. It is a 3-way tuple (<span class="code">ylow</span>,
<span class="code">yhigh</span>, <span class="code">min_interval</span>), where
<span class="code">ymin</span> and <span class="code">ymax</span> are the minimum
and maximum y-axis values, respectively, and <span class="code">min_interval</span>
is the minimum tick interval. If set to &#39;<span class="code">None</span>&#39;, the corresponding
value will be automatically chosen. So, in this example, we are letting
<span class="code">weewx</span> pick sensible y minimum and maximum values, but
we are requiring that the tick increment (<span class="code">min_interval</span>)
be at least 0.02. </p>
<p>Continuing on with the example above, there will be only one plot &quot;line&quot; (it
will actually be a series of bars) and it will have logical name &quot;<span class="code">rain</span>&quot;.
Because we haven&#39;t said otherwise, the SQL data type to be used for this line will
be the same as its logical name, that is, <span class="code">rain</span>, b, but
this can be overridden (see below). The aggregation type will be summing (overriding
the averaging specified in sub-section <span class="code">[[month_images]]</span>),
so you get the total rain over the aggregate period (rather than the average) over
an aggregation interval of 86,400 seconds (one day). The plot line will be titled
with the indicated label (&#39;<span class="code">Rain (daily avg)</span>&#39;)</p>
<h3>Including more than one SQL type in a plot</h3>
<p>More than one SQL type can be included in a plot. For example, here&#39;s how to
generate a plot with the week&#39;s outside temperature as well as dewpoint:</p>
<pre>[[[monthtempdew]]]
[[[[outTemp]]]]
[[[[dewpoint]]]]</pre>
<p>This would create an image in file <span class="code">monthtempdew.png</span>
that includes a line plot of both outside temperature and dewpoint.</p>
<h3>Including the same SQL type more than once in a plot</h3>
<p>Another example. Say you want a plot of the day&#39;s temperature, overlaid with
hourly averages. Here, you are using the same data type (&#39;<span class="code">outTemp</span>&#39;)
for both plot lines, the first with averages, the second without. If you do the
obvious it won&#39;t work:</p>
<pre>## WRONG ##
[[[[[[daytemp_with_avg]]]
[[[[outTemp]]]]
aggregate_type = avg
aggregate_interval = 3600
[[[[outTemp]]]] # OOPS! The same section name appears more than once!</pre>
<p>The option parser does not allow the same section name (&#39;<span class="code">outTemp</span>&#39;
in this case) to appear more than once at a given level in the configuration file,
so an error will be declared (technical reason: formally, the sections are an unordered
dictionary). If you wish for the same SQL type to appear more than once in a plot
then there is a trick you must know: use option <span class="code">data_type</span>.
This will override the default action that the logical line name is used for the
SQL type. So, our example would look like this:</p>
<pre>[[[daytemp_with_avg]]]
[[[[a_logical_name]]]]
data_type = outTemp
aggregate_type = avg
aggregate_interval = 3600
label = Avg. Temp.
[[[[outTemp]]]]</pre>
<p>Here, the first logical line has been given the name &quot;<span class="code">a_logical_name</span>&quot;
to distinguish it from the second line &quot;<span class="code">outTemp</span>&quot;. We have
specified that the first line will use data type <span class="code">outTemp</span>
and that it will use averaging over a one hour period. The second also uses
<span class="code">outTemp</span>, but will not use averaging.</p>
<p>The result is a nice plot of the day&#39;s temperature, overlaid with a 3-hour smoothed
average:</p>
<p class="center">
<img alt="Daytime temperature with running average" height="180" src="daytemp_with_avg.png" width="300" /></p>
<h3>Progressive vector plots</h3>
<p><span class="code">Weewx</span> can produce progressive vector plots as well
as the more conventional x-y plots. To produce these, use plot type &#39;<span class="code">vector</span>&#39;.
You need a vector type to produce this kind of plot. There are two: &#39;<span class="code">windvec</span>&#39;,
and &#39;<span class="code">windgustvec</span>&#39;. While they don&#39;t actually appear in
the SQL database, <span class="code">weewx</span> understands that they represent
special vector-types. The first, &#39;<span class="code">windvec</span>&#39;, represents
the average wind in an archive period, the second, &#39;<span class="code">windgustvec</span>&#39;
the max wind in an archive period. Here&#39;s how to produce a progressive vector for
one week that shows the hourly biggest wind gusts, along with hourly averages:</p>
<pre>[[[weekgustoverlay]]]
aggregate_interval = 3600
[[[[windvec]]]]
label = Hourly Wind
plot_type = vector
aggregate_type = avg
[[[[windgustvec]]]]
label = Gust Wind
plot_type = vector
aggregate_type = max</pre>
<p>This will produce an image file with name <span class="code">weekgustoverlay.png</span>.
It will consist of two progressive vector plots, both using hourly aggregation (3,600
seconds). For the first set of vectors, the hourly average will be used. In the
second, the max of the gusts will be used:</p>
<p class="center">
<img alt="hourly average wind vector overlaid with gust vectors" height="180" src="weekgustoverlay.png" width="300" /></p>
<p>By default, the sticks in the progressive wind plots point towards the wind source.
That is, the stick for a wind from the west will point left. If you have a chronic
wind direction (as I do), you may want to rotate the default direction so that all
the vectors don&#39;t line up over the x-axis, overlaying each other. Do this by using
option <span class="code">vector_rotate</span>. For example, with my chronic westerlies,
I set <span class="code">vector_rotate</span> to 90.0 for the plot above, so winds
out of the west point straight up. </p>
<p>If you use this kind of plot (the out-of-the-box version of
<span class="code">weewx</span> includes daily, weekly, monthly, and yearly progressive
wind plots), a small compass rose will be put in the lower-left corner of the image
to show the orientation of North.</p>
<h3>Overriding values</h3>
<p>Remember that values at any level can override values specified at a higher level.
For example, say you want to generate the standard plots, but for a few key observation
types such as barometer, you want to also generate some oversized plots to give
you extra detail, perhaps for an HTML popup. The standard <span class="code">weewx.conf</span>
file specifies plot size of 300x180 pixels, which will be used for all plots unless
overridden:</p>
<pre>[Images]
...
image_width=300
image_height = 180</pre>
<p>The standard plot of barometric pressure will appear in <span class="code">daybarometer.png</span>:</p>
<pre> [[[daybarometer]]]
[[[[barometer]]]] </pre>
<p>We now add our special plot of barometric pressure, but specify a larger image
size. This image will be put in file an class=&quot;code&quot; daybarometer_big.png.</p>
<pre> [[[daybarometer_big]]]
image_width = 600
image_height = 360
[[[[barometer]]]]</pre>
<h2 class="config_section">[Generators]</h2>
<p class="config_option">generator_list</p>
<p>This option controls which generators get run for this skin. It is a comma separated
list. The generators will be run in this order.</p>
<h2 class="config_section">&nbsp;</h2>
<h1>4. <a name="Customizing_the_weewx_service_engine">Customizing the
<span class="code">weewx</span> service engine</a></h1>
<p>This is an advance topic intended for those who wish to try their hand at extending
the internal engine in weewx. You should have a passing familiarity with Python
or, at least, be willing to learn it.</p>
<p>At a high level, weewx consists of an <em>engine</em> that is responsible for
managing a set of <em>services</em>. A service consists of a Python class with a
set of member functions. The engine arranges to have appropriate member functions
called when specific events happen. For example, when a new LOOP packet becomes
available, member function <span class="code">newLoopPacket()</span> of all services
is called.</p>
<p>To customize, you can</p>
<ul>
<li>Customize a service</li>
<li>Add a service</li>
<li>Customize the engine</li>
</ul>
<p>This section describes how to do all three.</p>
<p>The default install of <span class="code">weewx</span> includes the following
services:</p>
<table align="center" style="width: 60%">
<tr>
<td><strong>Service</strong></td>
<td><strong>Function</strong></td>
</tr>
<tr>
<td><span class="code">weewx.wxengine.StdCalibrate</span></td>
<td>Adjust new LOOP and archive packets using calibration expressions.</td>
</tr>
<tr>
<td><span class="code">weewx.wxengine.StdQC</span></td>
<td>Check that observation values fall within a specified range.</td>
</tr>
<tr>
<td><span class="code">weewx.wxengine.StdArchive</span></td>
<td>Archive any new data to the SQL databases.</td>
</tr>
<tr>
<td><span class="code">weewx.wxengine.StdTimeSynch</span></td>
<td>Arrange to have the clock on the station synchronized at regular intervals.</td>
</tr>
<tr>
<td><span class="code">weewx.wxengine.StdPrint</span></td>
<td>Print out new LOOP and archive packets on the console.</td>
</tr>
<tr>
<td><span class="code">weewx.wxengine.StdRESTful</span></td>
<td>Start a thread to manage
<a href="http://en.wikipedia.org/wiki/Representational_State_Transfer">RESTful</a>
(simple stateless client-server protocols) connections; such as those used
by the Weather Underground or PWSweather.</td>
</tr>
<tr>
<td><span class="code">weewx.wxengine.StdReportService</span></td>
<td>Launch a new thread to do report processing after a new archive record
arrives. Reports do things such as generate HTML files, generate images,
or FTP files to a web server. New reports can be added easily by the user.</td>
</tr>
</table>
<h2>Customizing a Service</h2>
<p>The service <span class="code">weewx.wxengine.StdPrint</span> prints out new
LOOP and archive packets to the console when they arrive. By default, it prints
out time, barometer, outside temperature, wind speed, and wind direction. Suppose
you don&#39;t like this, and want to print out humidity as well when a new LOOP packet
arrives. This could be done by subclassing the default print service
<span class="code">StdPrint</span> and overriding member function
<span class="code">newLoopPacket()</span>. </p>
<p>In file <span class="code">myprint.py</span>:</p>
<pre>from weewx.wxengine import StdPrint
from weeutil.weeutil import timestamp_to_string
class MyPrint(StdPrint):
# Override the default processLoopPacket:
def newLoopPacket(self, loop_packet):
print &quot;LOOP: &quot;, timestamp_to_string(loop_packet[&#39;dateTime&#39;]),\
loop_packet[&#39;barometer&#39;],\
loop_packet[&#39;outTemp&#39;],\
loop_packet[&#39;outHumidity&#39;],\
loop_packet[&#39;windSpeed&#39;],\
loop_packet[&#39;windDir&#39;]</pre>
<p>You then need to specify that your print service class should be loaded instead
of the default <span class="code">StdPrint</span> service. This is done by substituting
your service name for the standard print service name in the option
<span class="code">service_list</span>, located in <span class="code">[Engines][[WxEngine]]</span>:</p>
<pre>[Engines]
[[WxEngine]]
service_list = weewx.wxengine.StdCalibrate, weewx.wxengine.StdArchive, weewx.wxengine.StdTimeSynch, weewx.wxengine.MyPrint, weewx.wxengine.StdRESTful, weewx.wxengine.StdReportService</pre>
<p>e that this list must be all on one line. The parser <span class="code">ConfigObj</span>
does not allow options to be continued on to following lines.)</p>
<h2>Adding a Service</h2>
<p>Suppose there is no service that can be easily customized for your needs. In
this case, a new one can easily be created by subclassing off the abstract base
class <span class="code">StdService</span>, and then adding the functionality you
need. Here&#39;s an example that implements an alarm that sends off an email when an
arbitrary expression evaluates True. This example is included in the standard distribution
in subdirectory &quot;<span class="code">examples</span>&quot;.</p>
<p>File <span class="code">examples/alarm.py</span>:</p>
<pre>import time
import smtplib
from email.mime.text import MIMEText
import threading
import syslog
from weewx.wxengine import StdService
from weeutil.weeutil import timestamp_to_string
# Inherit from the base class StdService:
class MyAlarm(StdService):
&quot;&quot;&quot;Custom service that sounds an alarm if an arbitrary expression evaluates true&quot;&quot;&quot;
def __init__(self, engine, config_dict):
# Pass the initialization information on to my superclass:
super(MyAlarm, self).__init__(engine, config_dict)
# This will hold the time when the last alarm message went out:
self.last_msg_ts = None
try:
# Dig the needed options out of the configuration dictionary.
# If a critical option is missing, an exception will be thrown and
# the alarm will not be set.
self.expression = config_dict[&#39;Alarm&#39;][&#39;expression&#39;]
self.time_wait = int(config_dict[&#39;Alarm&#39;].get(&#39;time_wait&#39;, 3600))
self.smtp_host = config_dict[&#39;Alarm&#39;][&#39;smtp_host&#39;]
self.smtp_user = config_dict[&#39;Alarm&#39;].get(&#39;smtp_user&#39;)
self.smtp_password = config_dict[&#39;Alarm&#39;].get(&#39;smtp_password&#39;)
self.TO = config_dict[&#39;Alarm&#39;][&#39;mailto&#39;]
syslog.syslog(syslog.LOG_INFO, &quot;alarm: Alarm set for expression: \&quot;%s\&quot;&quot; % self.expression)
except:
self.expression = None
self.time_wait = None
def newArchivePacket(self, rec):
# Let the super class see the record first:
StdService.newArchivePacket(self, rec)
# See if the alarm has been set:
if self.expression:
# To avoid a flood of nearly identical emails, this will do
# the check only if we have never sent an email, or if we haven&#39;t
# sent one in the last self.time_wait seconds:
if not self.last_msg_ts or abs(time.time() - self.last_msg_ts) &gt;= self.time_wait :
# Evaluate the expression in the context of &#39;rec&#39;.
# Sound the alarm if it evaluates true:
if eval(self.expression, None, rec): # NOTE 1
# Sound the alarm!
# Launch in a separate thread so it doesn&#39;t block the main LOOP thread:
t = threading.Thread(target = MyAlarm.soundTheAlarm, args=(self, rec))
t.start()
# Record when the message went out:
self.last_msg_ts = time.time()
def soundTheAlarm(self, rec):
&quot;&quot;&quot;This function is called when the given expression evaluates True.&quot;&quot;&quot;
# Get the time and convert to a string:
t_str = timestamp_to_string(rec[&#39;dateTime&#39;])
# Form the message text:
msg_text = &quot;Alarm expression \&quot;%s\&quot; evaluated True at %s\nRecord:\n%s&quot; % (self.expression, t_str, str(rec))
# Convert to MIME:
msg = MIMEText(msg_text)
# Fill in MIME headers:
msg[&#39;Subject&#39;] = &quot;Alarm message from weewx&quot;
msg[&#39;From&#39;] = &quot;weewx&quot;
msg[&#39;To&#39;] = self.TO
# Create an instance of class SMTP for the given SMTP host:
s = smtplib.SMTP(self.smtp_host)
try:
# Some servers (eg, gmail) require encrypted transport.
# Be prepared to catch an exception if the server
# doesn&#39;t support it.
s.ehlo()
s.starttls()
s.ehlo()
except smtplib.SMTPException:
pass
# If a username has been given, assume that login is required for this host:
if self.smtp_user:
s.login(self.smtp_user, self.smtp_password)
# Send the email:
s.sendmail(msg[&#39;From&#39;], [self.TO], msg.as_string())
# Log out of the server:
s.quit()
# Log it in the system log:
syslog.syslog(syslog.LOG_INFO, &quot;alarm: Alarm sounded for expression: \&quot;%s\&quot;&quot; % self.expression)
syslog.syslog(syslog.LOG_INFO, &quot; *** email sent to: %s&quot; % self.TO)</pre>
<p>This service expects all the information it needs to be in the configuration
file <span class="code">weewx.conf</span> in a new section called
<span class="code">[Alarm]</span>. So, add the following lines to your configuration
file:</p>
<pre>[Alarm]
expression = &quot;outTemp &lt; 40.0&quot;
time_wait = 3600
smtp_host = smtp.mymailserver.com
smtp_user = myusername
smtp_password = mypassword
mailto = auser@adomain.com</pre>
<p>These options specify that the alarm is to be sounded when &quot;<span class="code">outTemp
&lt; 40.0</span>&quot; evaluates <span class="code">True</span>, that is when the outside
temperature is below 40.0 degrees. Any valid Python expression can be used, although
the only variables available are those in the current archive record. (The place
in the code where the expression is evaluated is marked with &quot;<span class="code">NOTE
1</span>&quot;.)</p>
<p>Another example expression could be:</p>
<pre> expression = &quot;outTemp &lt; 32.0 and windSpeed &gt; 10.0&quot;</pre>
<p>In this case, the alarm is sounded if the outside temperature drops below freezing
and the wind speed is greater than 10.0. </p>
<p>Option <span class="code">time_wait</span> is used to avoid a flood of nearly
identical emails. The new service will wait this long before sending another email
out.</p>
<p>Email will be sent through the SMTP host specified by option
<span class="code">smtp_host</span>. The recipient is specified in option
<span class="code">mailto</span>.</p>
<p>Many SMTP hosts require user login. If this is the case, the user and password
are specified with options <span class="code">smtp_user</span> and
<span class="code">smtp_password</span>, respectively.</p>
<p>To make this all work, you must tell the engine to load this new service. This
is done by adding your service name to the list <span class="code">service_list</span>,
located in <span class="code">[Engines][[WxEngine]]</span>:</p>
<pre>[Engines]
[[WxEngine]]
service_list = weewx.wxengine.StdCalibrate, weewx.wxengine.StdArchive, weewx.wxengine.StdTimeSynch, weewx.wxengine.StdPrint, weewx.wxengine.StdRESTful, weewx.wxengine.StdReportService, examples.alarm.MyAlarm</pre>
<p>(Again, the list must be all on one line.)</p>
<p>In addition to the example above, the distribution also includes a low-battery
alarm (<span class="code">lowBattery.py</span>), which is very similar, except that
it intercepts LOOP events (instead of archiving events).</p>
<h2><a name="Customizing_the_Engine">Customizing the Engine</a></h2>
<p>In this section, we look at how to install a custom Engine. In general, this
is the least desirable way to proceed, but in some cases it may be the only way
to get what you want.</p>
<p>For example, suppose you want to define a new event for when the first archive
of a day arrives. This can be done by extending the the standard engine. </p>
<p>This example is in file <span class="code">example/daily.py</span>:</p>
<pre>from weewx.wxengine import StdEngine, StdService
from weeutil.weeutil import startOfArchiveDay
class MyEngine(StdEngine):
&quot;&quot;&quot;A customized weewx engine.&quot;&quot;&quot;
def __init__(self, *args, **vargs):
# Pass on the initialization data to my superclass:
StdEngine.__init__(self, *args, **vargs)
# This will record the timestamp of the old day
self.old_day = None
def newArchivePacket(self, rec):
# First let my superclass process it:
StdEngine.newArchivePacket(self, rec)
# Get the timestamp of the start of the day using
# the utility function startOfArchiveDay
dayStart_ts = startOfArchiveDay(rec[&#39;dateTime&#39;])
# Call the function newDay() if either this is
# the first archive since startup, or if a new day has started
if not self.old_day or self.old_day != dayStart_ts:
self.old_day = dayStart_ts
self.newDay(rec) # NOTE 1
def newDay(self, rec):
&quot;&quot;&quot;Called when the first archive record of a day arrives.&quot;&quot;&quot;
# Go through the list of service objects. This
# list is actually in my superclass StdEngine.
for svc_obj in self.service_obj:
# Because this is a new event, not all services will
# be prepared to accept it. Be prepared for an AttributeError
# exception:
try: # NOTE 2
svc_obj.firstArchiveOfDay(rec)
except AttributeError:
pass</pre>
<p>This customized engine works by monitoring the arrival of archive records, and
checking their time stamp (<span class="code">rec[&#39;dateTime&#39;]</span>. It calculates
the time stamp for the start of the day, and if it changes, calls member function
<span class="code">newDay()</span> (NOTE 1). </p>
<p>The member function <span class="code">newDay()</span> then goes through the
list of services (attribute <span class="code">self.service_obj</span>). Because
this engine is defining a new event (first archive of the day), the existing services
may not be prepared to accept it. So, be prepared to catch an exception
<span class="code">AttributeError</span> if the service does not define it (NOTE
2).</p>
<p>To use this engine, go into file <span class="code">weewxd.py</span> and change
the line</p>
<pre>weewx.wxengine.main()</pre>
<p>so that it uses your new engine:</p>
<pre>from examples.daily import MyEngine
# Specify that my specialized engine should be used instead
# of the default:
weewx.wxengine.main(EngineClass = MyEngine)</pre>
<p>We now have a new engine that defines a new event (&quot;<span class="code">firstArchiveOfDay</span>&quot;),
but there is no service to take advantage of it. We define a new service:</p>
<pre># Define a new service to take advantage of the new event
class DailyService(StdService):
&quot;&quot;&quot;This service can do something when the first archive record of
a day arrives.&quot;&quot;&quot;
def firstArchiveOfDay(self, rec):
&quot;&quot;&quot;Called when the first archive record of a day arrives.&quot;&quot;&quot;
print &quot;The first archive of the day has arrived!&quot;
print rec
# You might want to do something here like run a cron job</pre>
<p>This service will simply print out a notice and then print out the new record.
However, if there is some daily processing you want to do, such as running a backup,
or running utility <a href="http://www.weewx.com/wunderfixer">wunderfixer</a>, this
would be the place to do it.</p>
<p>The final step is to go into your configuration file and specify that this new
service be loaded, by adding its class name to option <span class="code">service_list</span>:</p>
<pre>[Engines]
[[WxEngine]]
# The list of services the main weewx engine should run:
service_list = weewx.wxengine.StdCalibrate, weewx.wxengine.StdArchive, weewx.wxengine.StdTimeSynch, weewx.wxengine.StdPrint, weewx.wxengine.StdRESTful, weewx.wxengine.StdReportService, examples.daily.DailyService</pre>
<p>(Again, the list must be all on one line.)</p>
<h1>Appendix A: <a name="Archive_types">Archive types</a></h1>
<p><em>Archive types</em> are weather observations that have come from your instrument
and been stored in the <em>archive database, </em>&nbsp;a SQL database. They represent
the <em>current conditions</em> as of some time. They are available to be used in
two places:</p>
<ul>
<li>In your template files as a tag with period <span class="code">$current</span>.
Hence, the tag <span class="code">$current.outTemp</span> represents the latest
current outside temperature. There is no aggregation involved (see
<a href="#Statistical_types">statistical types</a> for aggregation).</li>
<li>In your plot graphs. Here, a line in the graph represents the set of current
observations over a time period. While each plot point in a graph may represent
an aggregation, do not confuse this aggregation with the statistical aggregation.
The former is done with the archive database, the latter with the statistical
database.</li>
</ul>
<p>The following table shows all the possible archive types and whether they can
be used in tag <span class="code">$current</span> or in a plot. Note that just because
a type appears in the table does not necessarily mean that it is available for
<em>your</em> station setup. That would depend on whether your instrument supports
the type.</p>
<table align="center" style="width: 80%">
<tr>
<td><strong>Archive Type</strong></td>
<td style="width: 200px"><strong>SQL Type</strong><br />
<span class="xxsmall">(appears in archive database)</span></td>
<td><strong>Can be used<br />
in plots</strong></td>
<td><strong>Can be used<br />
in tag <span class="code">$current</span></strong></td>
</tr>
<tr>
<td class="code">altimeter</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">barometer</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">consBatteryVoltage</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">dateTime</td>
<td>X</td>
<td></td>
<td>X (represents current time)</td>
</tr>
<tr>
<td class="code">dewpoint</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">ET</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">extraHumid1</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">extraHumid2</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">extraTemp1</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">extraTemp2</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">extraTemp3</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">hail</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">hailRate</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">heatindex</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">heatingTemp</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">heatingVoltage</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">inHumidity</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">inTemp</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">inTempBatteryStatus</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">interval</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">leafTemp2</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">leafWet2</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">outHumidity</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">outTemp</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">outTempBatteryStatus</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">pressure</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">radiation</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">rain</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">rainBatteryStatus</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">rainRate</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">referenceVoltage</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">rxCheckPercent</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">soilMoist1</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">soilMoist2</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">soilMoist3</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">soilMoist4</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">soilTemp1</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">soilTemp2</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">soilTemp3</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">soilTemp4</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">supplyVoltage</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">txBatteryStatus</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">usUnits</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">UV</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">windvec</td>
<td>&nbsp;</td>
<td>X (special vector type)</td>
<td>&nbsp;</td>
</tr>
<tr>
<td class="code">windBatteryStatus</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">windDir</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">windGust</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">windGustDir</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">windSpeed</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">windchill</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
</table>
<h1>Appendix B: <a name="Units">Units</a></h1>
<p>The table below lists all the unit groups, their members, and which units are
options for the group.</p>
<table align="center" style="width: 60%">
<tr>
<td><strong>Group</strong></td>
<td><strong>Members</strong></td>
<td><strong>Unit options</strong></td>
</tr>
<tr>
<td class="code">group_altitude</td>
<td class="code">altitude</td>
<td class="code">foot<br />
meter</td>
</tr>
<tr class="code">
<td>group_direction</td>
<td>gustdir<br />
vecdir<br />
windDir<br />
windGustDir</td>
<td>degree_compass</td>
</tr>
<tr class="code">
<td>group_moisture</td>
<td>soilMoist1<br />
soilMoist2<br />
soilMoist3<br />
soilMoist4</td>
<td>centibar</td>
</tr>
<tr class="code">
<td>group_percent</td>
<td>extraHumid1<br />
extraHumid2<br />
inHumidity<br />
outHumidity<br />
rxCheckPercent</td>
<td>percent</td>
</tr>
<tr class="code">
<td>group_pressure</td>
<td>barometer<br />
altimeter<br />
pressure</td>
<td>inHg<br />
mbar<br />
hPa</td>
</tr>
<tr class="code">
<td>group_radiation</td>
<td>UV<br />
radiation</td>
<td>watt_per_meter_squared</td>
</tr>
<tr class="code">
<td>group_rain</td>
<td>rain<br />
ET<br />
hail</td>
<td>in<br />
cm<br />
mm</td>
</tr>
<tr class="code">
<td>group_rainrate</td>
<td>rainRate<br />
hailRate</td>
<td>in_per_hour<br />
cm_per_hour<br />
mm_per_hour</td>
</tr>
<tr class="code">
<td>group_speed</td>
<td>wind<br />
windGust<br />
windSpeed<br />
windgustvec<br />
windvec</td>
<td>mile_per_hour<br />
km_per_hour<br />
knot<br />
meter_per_second</td>
</tr>
<tr class="code">
<td>group_speed2</td>
<td>rms<br />
vecavg</td>
<td>mile_per_hour2<br />
km_per_hour2<br />
knot2<br />
meter_per_second2</td>
</tr>
<tr class="code">
<td>group_temperature</td>
<td>dewpoint<br />
extraTemp1<br />
extraTemp2<br />
extraTemp3<br />
heatindex<br />
heatingTemp<br />
inTemp<br />
leafTemp1<br />
leafTemp2<br />
outTemp<br />
soilTemp1<br />
soilTemp2<br />
soilTemp3<br />
soilTemp4<br />
windchill</td>
<td>degree_F<br />
degree_C</td>
</tr>
<tr class="code">
<td>group_degree_day</td>
<td>heatdef<br />
cooldeg</td>
<td>degree_F_day<br />
degree_C_day</td>
</tr>
<tr class="code">
<td>group_volt</td>
<td>consBatteryVoltage<br />
heatingVoltage<br />
referenceVoltage<br />
supplyVoltage</td>
<td>volt</td>
</tr>
<tr class="code">
<td>group_NONE</td>
<td>NONE</td>
<td>NONE</td>
</tr>
</table>
<h1>Appendix C: <a name="Statistical_types">Statistical types</a></h1>
<p>Most of the templates are devoted to reporting <em>statistical types</em>, such
as temperature, wind, or rainfall, using various <em>aggregates</em>, such as min,
max, or sum. These are called <em>aggregations</em>, because they are a summary
of lots of underlying data. However, only certain aggregates make sense for certain
statistical types. For example, heat degree days is defined on a daily basis, so
while the day&#39;s average temperature is meaningful, the day&#39;s heating degree days
do not.</p>
<p>The following table defines which aggregates are available to be used in your
template for which statistical types (assuming your station supports them and you
have specified that it be stored in your stats database. See section
<span class="code"><a href="readme.htm#[Stats]">[Stats]</a></span> in the
<span class="code">weewx.conf</span> configuration file).</p>
<table style="width: 100%">
<tr>
<td><em>Stats Type</em></td>
<td class="code">min</td>
<td class="code">mintime</td>
<td class="code">max</td>
<td class="code">maxtime</td>
<td class="code">avg</td>
<td class="code">sum</td>
<td class="code">rms</td>
<td class="code">vecavg</td>
<td class="code">vecdir</td>
</tr>
<tr>
<td class="code">barometer</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
</tr>
<tr>
<td class="code">inTemp</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
</tr>
<tr>
<td class="code">outTemp</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
</tr>
<tr>
<td class="code">inHumidity</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
</tr>
<tr>
<td class="code">outHumidity</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
</tr>
<tr>
<td class="code">wind</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>&nbsp;</td>
<td>X</td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td class="code">rain</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
</tr>
<tr>
<td class="code">dewpoint</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
</tr>
<tr>
<td class="code">windchill</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
</tr>
<tr>
<td class="code">heatindex</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
</tr>
<tr>
<td class="code">heatdeg</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>X</td>
<td>X</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
</tr>
<tr>
<td class="code">cooldeg</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>X</td>
<td>X</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
</tr>
<tr>
<td class="code">ET</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
</tr>
<tr>
<td class="code">radiation</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
</tr>
<tr>
<td class="code">UV</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
</tr>
<tr>
<td class="code">extraTemp1<br />
extraTemp2<br />
extraTemp3</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
</tr>
<tr>
<td class="code">soilTemp1<br />
soilTemp2<br />
soilTemp3</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
</tr>
<tr>
<td class="code">leafTemp1<br />
leafTemp2</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
</tr>
<tr>
<td class="code">extraHumid1<br />
extraHumid2</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
</tr>
<tr>
<td class="code">soilMoist1<br />
soilMoist2<br />
soilMoist3<br />
soilMoist4</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
</tr>
<tr>
<td class="code">leafWet1<br />
leafWet2</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
</tr>
<tr>
<td class="code">rxCheckPercent</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>X</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
<td>&nbsp;</td>
</tr>
</table>
<p>&nbsp;</p>
<h1>Appendix D: <a name="Packet_types">Packet types</a></h1>
<p><em>Packets</em> are the raw data coming off the instrument (as opposed to
<em>records</em>, which are stored on the database). The observation types
available in a packet are useful when setting <em><a href="readme.htm#QC">
quality control rules</a></em> and when doing <em>
<a href="readme.htm#Calibrate">calibrations</a></em>.</p>
<p>They may also be useful if you are writing your own custom service. In particular, for subclasses of <span class="code">StdService</span>, member function
<span class="code">newLoopPacket</span> is called when new LOOP packets arrive,
and member function <span class="code">newArchivePacket</span> is called when new
archive packets arrive. For both functions, the only argument (besides
<span class="code">self</span>) is a dictionary, where the key is the type
listed below, and the value is the observation value.</p>
<p>See the guide from <em>
<a href="http://www.davisnet.com/support/weather/software_dllsdk.asp">Vantage Pro
and Pro2 Serial Communications Reference</a></em> (available on the Davis website)
for more information about these types.</p>
<table align="center" class="style1" style="width: 50%">
<tr>
<td><strong><em>Type</em></strong></td>
<td><strong>Loop packet</strong></td>
<td><strong>Archive Packet</strong></td>
</tr>
<tr>
<td><span class="code">barometer</span></td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">consBatteryVoltage</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">dateTime</span></td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">dayET</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">dayRain</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">dewpoint</span></td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">ET</span> (hourly)</td>
<td>&nbsp;</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">extraAlarm1</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">extraAlarm2</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">extraAlarm3</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">extraAlarm4</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">extraAlarm5</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">extraAlarm6</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">extraAlarm7</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">extraAlarm8</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">extraHumid1</span></td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">extraHumid2</span></td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">extraHumid3</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">extraHumid4</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">extraHumid5</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">extraHumid6</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">extraHumid7</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">extraTemp1</span></td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">extraTemp2</span></td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">extraTemp3</span></td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">extraTemp4</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">extraTemp5</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">extraTemp6</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">extraTemp7</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">forecastIcon</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">forecastRule</span></td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">heatIndex</span></td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">highOutTemp</span></td>
<td>&nbsp;</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">highRadiation</span></td>
<td>&nbsp;</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">highUV</span></td>
<td>&nbsp;</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">inHumidity</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">inTemp</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">interval</span></td>
<td>&nbsp;</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">insideAlarm</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">leafTemp1</span></td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">leafTemp2</span></td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">leafTemp3</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">leafTemp4</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">leafWet1</span></td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">leafWet2</span></td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">leafWet3</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">leafWet4</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">lowOutTemp</span></td>
<td>&nbsp;</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">monthET</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">monthRain</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">outHumidity</span></td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">outTemp</span></td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">outsideAlarm1</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">outsideAlarm2</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">radiation</span></td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">rain</span></td>
<td>&nbsp;</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">rainAlarm</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">rainRate</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">rxCheckPercent</span></td>
<td>&nbsp;</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">soilLeafAlarm1</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">soilLeafAlarm2</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">soilLeafAlarm3</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">soilLeafAlarm4</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">soilMoist1</span></td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">soilMoist2</span></td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">soilMoist3</span></td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">soilMoist4</span></td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">soilTemp1</span></td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">soilTemp2</span></td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">soilTemp3</span></td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">soilTemp4</span></td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">stormRain</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">stormStart</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">sunrise</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">sunset</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">txBatteryStatus</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">usUnits</span></td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">UV</span></td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">windChill</span></td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">windDir</span></td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">windGust</span></td>
<td>&nbsp;</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">windGustDir</span></td>
<td>&nbsp;</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">windSpeed10</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">windSpeed</span></td>
<td>X</td>
<td>X</td>
</tr>
<tr>
<td><span class="code">yearET</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
<tr>
<td><span class="code">yearRain</span></td>
<td>X</td>
<td>&nbsp;</td>
</tr>
</table>
</body>
</html>