readme: added build architecture doc

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BUILD.md

@@ -0,0 +1,126 @@
+# Kopia Build Architecture
+
+![Kopia](icons/kopia.svg)
+
+Kopia build pipeline is set up to generate the following artifacts:
+
+* Standalone `kopia` executable for all supported platforms, optionally with embedded graphical UI
+* KopiaUI - desktop app for all supported platforms: Windows, macOS, and Linux
+* The static content of [kopia.io](https://kopia.io) website
+
+Kopia build is based on `Makefile` and provides the following main targets:
+
+* `$ make install` - builds full `kopia` command-line executable that also embeds graphical UI components that can be used in a browser. The output is stored in `$HOME/go/bin/kopia`
+
+* `$ make install-noui` - builds simplified `kopia` executable without embedded graphical UI. The output is stored in `$HOME/go/bin/kopia`
+
+* `$ make install` - builds desktop application based on [Electron](https://electronjs.org) using [Electron Builder](https://electron.build) The output is stored in the `dist/kopia-ui` subdirectory
+
+* `$ make website` - builds [kopia.io](https://kopia.io) website using [Hugo](https://gohugo.io). The output is stored in `site/public` and published to [Github Pages](https://github.com/kopia/kopia.github.io) from [Travis CI](https://travis-ci.org/kopia/kopia) on each build.
+
+The project structure is also compatible with `go get`, so getting the latest Kopia command line tool (albeit without any UI functionality) is as simple as:
+
+```
+$ go get github.com/kopia/kopia
+```
+
+## Build Pipeline Overview
+
+The following picture provides high-level overview of the build pipeline.
+
+![Build Architecture](build_architecture.svg)
+
+## HTML UI
+
+THe HTML UI builds HTML-based user interface that is embedded in Kopia binary by using [go-bindata](github.com/go-bindata/go-bindata).
+
+The UI is build using [React](https://reactjs.org) and more specifically [Create React App](https://reactjs.org/docs/create-a-new-react-app.html#create-react-app) toolchain.
+
+When developing the UI, the most convenient way is to use two terminals. The first terminal runs `kopia server` without the UI. The second one runs development server of React with hot-reload, so changes are immediately reflected in the browser. 
+
+In the first terminal do:
+
+```shell
+$ make install-noui && $HOME/go/bin/kopia server
+```
+
+In the second terminal do:
+
+```shell
+$ make -C htmlui dev
+```
+
+This will automatically open the browser with the UI page on http://localhost:3000. Changing any file under `htmlui/` will cause the browser to hot-reload the change. In most cases, the changes to the kopia server don't even require reloading the browser.
+
+To make sure HTML pages compile correctly use:
+
+```shell
+$ make -C htmlui build-html
+```
+
+To convert generated HTML to embedded go source code use:
+
+```shell
+$ make html-ui-bindata
+```
+
+To manually build the `kopia` binary with the embedded HTML that was just generated in the previous step:
+
+```shell
+$ go install -tags embedhtml
+```
+or
+```shell
+$ make install
+```
+
+When compiling Go code without `embedhtml` build tag, the embedded UI will be just a placeholder. This is equivalent to:
+
+```shell
+$ make install-noui
+```
+
+## KopiaUI App
+
+KopiaUI is built using [Electron](https://electronjs.org) and packaged as native binary using [Electron Builder](https://electron.build). The app is just a shell that invokes `kopia server --ui` and connects the browser to it, plus it provides native system tray integration. Kopia executable is embedded as a resource inside KopiaUI app, to simplify usage.
+
+To build the app:
+
+```shell
+$ make kopia-ui
+```
+
+The generated app will be in:
+
+* `dist/kopia-ui/win-unpacked` on Windows
+* `dist/kopia-ui/mac/KopiaUI.app` - on macOS
+* `dist/kopia-ui/linux-unpacked` on Linux
+
+When developing the app shell it is convenient to simply run Electron directly on the source code without building.
+
+```shell
+$ make -C app dev
+```
+
+>NOTE: this also opens the browser window due to CRA development server, but it can be safely disregarded. Because KopiaUI configuration pages are built using CRA, they also benefit from hot-reload while developing this way.
+
+## Website
+
+The [kopia.io](https://kopia.io) website is built using [Hugo](https://gohugo.io).
+
+To build the website use:
+
+```shell
+$ make -C site build
+```
+
+This will auto-generate [Markdown](https://en.wikipedia.org/wiki/Markdown) files with documentation for currently supported Kopia CLI subcommands and store them under `site/content/docs/Reference/Command-Line` and then generate the website which is stored in `site/public`.
+
+To see the  website in a browser it's more convenient to use:
+
+```shell
+$ make -C site server
+```
+
+This starts a server on http://localhost:1313 where the website can be browsed.
+

README.md

@@ -30,6 +30,10 @@ Getting Started
 ---
 See [Documentation](https://kopia.io/docs/) for more information.
 
+Building Kopia
+---
+See [Build Infrastructure](BUILD.md) for more information on building Kopia and working with the source code.
+
 Licensing
 ---
 Kopia is licensed under the Apache License, Version 2.0. See [LICENSE](LICENSE) for the full license text.

htmlui/Makefile

@@ -5,8 +5,9 @@ include ../tools/tools.mk
 dev: node_modules
 	$(npm) $(npm_flags) run start
 
+# build HTML, run in CI mode which is more strict
 build-html: node_modules
-	$(npm) $(npm_flags) run build
+	CI=true $(npm) $(npm_flags) run build
 
 node_modules: $(npm)
 	$(npm) $(npm_flags) install

site/Makefile

@@ -1,6 +1,6 @@
 # don't put tools under current directory, otherwise 'make server' fails because there are too
 # many open files due to 'node_modules'
-WATCH=true
+WATCH=false
 
 all: build