weewx/bin/weedb/tests/test_errors.py

"""Test the weedb exception hierarchy"""
from __future__ import with_statement
import os
import stat
import sys
import unittest

import weedb

#
# For these tests to work, the database for sqdb1 must in a place where you have write permissions,
# and the database for sqdb2 must be in a place where you do NOT have write permissions
sqdb1_dict = {'database_name': '/var/tmp/sqdb1.sdb', 'driver':'weedb.sqlite', 'timeout': '2'}
sqdb2_dict = {'database_name': '/usr/local/sqdb2.sdb', 'driver':'weedb.sqlite', 'timeout': '2'}
mysql1_dict  = {'database_name': 'test_weewx1', 'user':'weewx1', 'password':'weewx1', 'driver':'weedb.mysql'}
mysql2_dict  = {'database_name': 'test_weewx1', 'user':'weewx2', 'password':'weewx2', 'driver':'weedb.mysql'}

 
# Double check that we have the necessary permissions (or lack thereof):
try:
    fd = open(sqdb1_dict['database_name'], 'w')
    fd.close()
except:
    print >>sys.stderr, "For tests to work properly, you must have permission to write to '%s'." % sqdb1_dict['database_name']
    print >>sys.stderr, "Change the permissions and try again."
try:
    fd = open(sqdb2_dict['database_name'], 'w')
    fd.close()
except IOError:
    pass
else:
    print >>sys.stderr, "For tests to work properly, you must NOT have permission to write to '%s'." % sqdb2_dict['database_name']
    print >>sys.stderr, "Change the permissions and try again."

class Cursor(object):
    """Class to be used to wrap a cursor in a 'with' clause."""
    def __init__(self, db_dict):
        self.connection = weedb.connect(db_dict)
        self.cursor = self.connection.cursor()
 
    def __enter__(self):
        return self.cursor
 
    def __exit__(self, etyp, einst, etb):  # @UnusedVariable
        self.cursor.close()
        self.connection.close()

class Common(unittest.TestCase):
 
    def setUp(self):
        """Drop the old databases, in preparation for running a test."""
        try:
            import MySQLdb
        except ImportError as e:
            raise unittest.case.SkipTest(e.message)
        try:
            weedb.drop(mysql1_dict)
        except weedb.NoDatabase:
            pass
        try:
            weedb.drop(sqdb1_dict)
        except weedb.NoDatabase:
            pass

    def test_bad_host(self):
        mysql_dict = dict(mysql1_dict)
        mysql_dict['host'] = 'foohost'
        with self.assertRaises(weedb.CannotConnectError):
            weedb.connect(mysql_dict)

    def test_bad_password(self):
        mysql_dict = dict(mysql1_dict)
        mysql_dict['password'] = 'badpw'
        with self.assertRaises(weedb.BadPasswordError):
            weedb.connect(mysql_dict)
            
    def test_drop_nonexistent_database(self):
        with self.assertRaises(weedb.NoDatabase):
            weedb.drop(mysql1_dict)
        with self.assertRaises(weedb.NoDatabase):
            weedb.drop(sqdb1_dict)
     
    def test_drop_nopermission(self):
        weedb.create(mysql1_dict)
        with self.assertRaises(weedb.PermissionError):
            weedb.drop(mysql2_dict)
        weedb.create(sqdb1_dict)
        # Can't really test this one without setting up a file where
        # we have no write permission
        with self.assertRaises(weedb.NoDatabaseError):
            weedb.drop(sqdb2_dict)
 
    def test_create_nopermission(self):
        with self.assertRaises(weedb.PermissionError):
            weedb.create(mysql2_dict)
        with self.assertRaises(weedb.PermissionError):
            weedb.create(sqdb2_dict)

    def test_double_db_create(self):
        weedb.create(mysql1_dict)
        with self.assertRaises(weedb.DatabaseExists):
            weedb.create(mysql1_dict)
        weedb.create(sqdb1_dict)
        with self.assertRaises(weedb.DatabaseExists):
            weedb.create(sqdb1_dict)
         
    def test_open_nonexistent_database(self):
        with self.assertRaises(weedb.OperationalError):
            connect=weedb.connect(mysql1_dict)
        with self.assertRaises(weedb.OperationalError):
            connect=weedb.connect(sqdb1_dict)
         
    def test_select_nonexistent_database(self):
        mysql_dict = dict(mysql1_dict)
        mysql_dict.pop('database_name')
        connect = weedb.connect(mysql_dict)
        cursor = connect.cursor()
        with self.assertRaises(weedb.NoTableError):
            cursor.execute("SELECT foo from test_weewx1.bar")
        cursor.close()
        connect.close()

        # There's no analogous operation with sqlite. You
        # must create the database in order to open it.
        
    def test_select_nonexistent_table(self):
        def test(db_dict):
            weedb.create(db_dict)
            connect = weedb.connect(db_dict)
            cursor = connect.cursor()
            cursor.execute("CREATE TABLE bar (col1 int, col2 int)")
            with self.assertRaises(weedb.NoTableError) as e:
                cursor.execute("SELECT foo from fubar")
            cursor.close()
            connect.close()
        
        test(mysql1_dict)
        test(sqdb1_dict)

    def test_double_table_create(self):
        def test(db_dict):
            weedb.create(db_dict)
            connect = weedb.connect(db_dict)
            cursor = connect.cursor()
            cursor.execute("CREATE TABLE bar (col1 int, col2 int)")
            with self.assertRaises(weedb.TableExistsError) as e:
                cursor.execute("CREATE TABLE bar (col1 int, col2 int)")
            cursor.close()
            connect.close()
         
        test(mysql1_dict)
        test(sqdb1_dict)

    def test_select_nonexistent_column(self):
        def test(db_dict):
            weedb.create(db_dict)
            connect = weedb.connect(db_dict)
            cursor = connect.cursor()
            cursor.execute("CREATE TABLE bar (col1 int, col2 int)")
            with self.assertRaises(weedb.NoColumnError) as e:
                cursor.execute("SELECT foo from bar")
            cursor.close()
            connect.close()
         
        test(mysql1_dict)
        test(sqdb1_dict)

    def test_duplicate_key(self):
        def test(db_dict):
            weedb.create(db_dict)
            connect = weedb.connect(db_dict)
            cursor = connect.cursor()
            cursor.execute("CREATE TABLE test1 ( dateTime INTEGER NOT NULL UNIQUE PRIMARY KEY, col1 int, col2 int)")
            cursor.execute("INSERT INTO test1 (dateTime, col1, col2) VALUES (1, 10, 20)")
            with self.assertRaises(weedb.IntegrityError) as e:
                cursor.execute("INSERT INTO test1 (dateTime, col1, col2) VALUES (1, 30, 40)")
            cursor.close()
            connect.close()

        test(mysql1_dict)
        test(sqdb1_dict)
        

if __name__ == '__main__':
    unittest.main()