Merge lp:~gmb/launchpad/bugzilla-3.4-dbtime into lp:launchpad

[Graham Binns]

[Graham Binns (gmb)]

This branch adds the ability to get the time from the remote server to
the BugzillaAPI ExternalBugTracker.

I've added a local implementation of the API method that we call so that
we can test properly without having to connect to an actual instance as
well as the implementation of getCurrentDBTime() itself. I've made some
minor changes to TestBugzillaXMLRPCTransport.time() to make it a little
more readable.

= Launchpad lint =

Checking for conflicts. and issues in doctests and templates.
Running jslint, xmllint, pyflakes, and pylint.
Using normal rules.

Linting changed files:
  lib/lp/bugs/doc/externalbugtracker-bugzilla-api.txt
  lib/lp/bugs/externalbugtracker/bugzilla.py
  lib/lp/bugs/tests/bugzilla-xmlrpc-transport.txt
  lib/lp/bugs/tests/externalbugtracker.py

[Celso Providelo (cprov)]

Hi Graham,

The change is flawless!

Thanks for improving the testing infrastructure readability while you were there.

r=me

review: Approve (code)

=== modified file 'lib/lp/bugs/doc/externalbugtracker-bugzilla-api.txt'
--- lib/lp/bugs/doc/externalbugtracker-bugzilla-api.txt	2009-08-19 13:12:30 +0000
+++ lib/lp/bugs/doc/externalbugtracker-bugzilla-api.txt	2009-08-20 15:43:37 +0000
@@ -75,3 +75,39 @@
         ...
     BugTrackerAuthenticationError: http://thiswillfail.example.com:
     Fault 300: The username or password you entered is not valid.
+
+
+Getting the server time
+-----------------------
+
+To be able to accurately sync with a bug tracker, we need to be able to
+check the time on the remote server. We use BugzillaAPI.getCurrentDBTime()
+to get the current time on the remote server.
+
+    # There's no way to create a UTC timestamp without monkey-patching
+    # the TZ environment variable. Rather than do that, we create our
+    # own datetime and work with that.
+    >>> from datetime import datetime
+    >>> remote_time = datetime(2009, 8, 19, 17, 2, 2)
+
+    >>> test_transport.local_datetime = remote_time
+    >>> bugzilla.getCurrentDBTime()
+    CALLED Bugzilla.time()
+    datetime.datetime(2009, 8, 19, 17, 2, 2, tzinfo=<UTC>)
+
+If the remote system is in a different timezone, getCurrentDBTime() will
+convert its time to UTC before returning it.
+
+    >>> test_transport.utc_offset = 60**2
+    >>> test_transport.timezone = 'CET'
+    >>> bugzilla.getCurrentDBTime()
+    CALLED Bugzilla.time()
+    datetime.datetime(2009, 8, 19, 16, 2, 2, tzinfo=<UTC>)
+
+This works whether the UTC offset is positive or negative.
+
+    >>> test_transport.utc_offset = -5 * 60**2
+    >>> test_transport.timezone = 'US/Eastern'
+    >>> bugzilla.getCurrentDBTime()
+    CALLED Bugzilla.time()
+    datetime.datetime(2009, 8, 19, 22, 2, 2, tzinfo=<UTC>)
 
=== modified file 'lib/lp/bugs/externalbugtracker/bugzilla.py'
--- lib/lp/bugs/externalbugtracker/bugzilla.py	2009-08-19 13:19:22 +0000
+++ lib/lp/bugs/externalbugtracker/bugzilla.py	2009-08-20 15:43:37 +0000
@@ -430,6 +430,34 @@
                 self.baseurl,
                 "Fault %s: %s" % (fault.faultCode, fault.faultString))
 
+    def getCurrentDBTime(self):
+        """See `IExternalBugTracker`."""
+        time_dict = self.xmlrpc_proxy.Bugzilla.time()
+
+        # Convert the XML-RPC DateTime we get back into a regular Python
+        # datetime.
+        server_db_timetuple = time.strptime(
+            str(time_dict['db_time']), '%Y%m%dT%H:%M:%S')
+        server_db_datetime = datetime(*server_db_timetuple[:6])
+
+        # The server's DB time is the one that we want to use. However,
+        # this may not be in UTC, so we need to convert it. Since we
+        # can't guarantee that the timezone data returned by the server
+        # is sane, we work out the server's offset from UTC by looking
+        # at the difference between the web_time and the web_time_utc
+        # values.
+        server_web_time = time.strptime(
+            str(time_dict['web_time']), '%Y%m%dT%H:%M:%S')
+        server_web_datetime = datetime(*server_web_time[:6])
+        server_web_time_utc = time.strptime(
+            str(time_dict['web_time_utc']), '%Y%m%dT%H:%M:%S')
+        server_web_datetime_utc = datetime(*server_web_time_utc[:6])
+
+        server_utc_offset = server_web_datetime - server_web_datetime_utc
+        server_utc_datetime = server_db_datetime - server_utc_offset
+
+        return server_utc_datetime.replace(tzinfo=pytz.timezone('UTC'))
+
 
 class BugzillaLPPlugin(BugzillaAPI):
     """An `ExternalBugTracker` to handle Bugzillas using the LP Plugin."""
 
=== modified file 'lib/lp/bugs/tests/bugzilla-xmlrpc-transport.txt'
--- lib/lp/bugs/tests/bugzilla-xmlrpc-transport.txt	2009-08-18 16:39:17 +0000
+++ lib/lp/bugs/tests/bugzilla-xmlrpc-transport.txt	2009-08-19 23:17:09 +0000
@@ -576,3 +576,36 @@
     Traceback (most recent call last):
       ...
     Fault: <Fault 300: 'The username or password you entered is not valid.'>
+
+
+Getting the current time
+------------------------
+
+The Bugzilla.time() method allows us to retrieve a dict of the time on
+the remote server.
+
+    >>> time_dict = server.Bugzilla.time()
+    >>> for key in sorted(time_dict):
+    ...     print "%s: %s" % (key, time_dict[key])
+    db_time: 20080501T01:01:01
+    tz_name: UTC
+    tz_offset: +0000
+    tz_short_name: UTC
+    web_time: 20080501T01:01:01
+    web_time_utc: 20080501T01:01:01
+
+If the remote server is in a different timezone, the db_time and
+web_time items will be in the server's local timezone whilst
+web_time_utc will be in UTC.
+
+    >>> bugzilla_transport.utc_offset = 60**2
+    >>> bugzilla_transport.timezone = 'CET'
+    >>> time_dict = server.Bugzilla.time()
+    >>> for key in sorted(time_dict):
+    ...     print "%s: %s" % (key, time_dict[key])
+    db_time: 20080501T01:01:01
+    tz_name: CET
+    tz_offset: +0100
+    tz_short_name: CET
+    web_time: 20080501T01:01:01
+    web_time_utc: 20080501T00:01:01
 
=== modified file 'lib/lp/bugs/tests/externalbugtracker.py'
--- lib/lp/bugs/tests/externalbugtracker.py	2009-08-18 16:41:18 +0000
+++ lib/lp/bugs/tests/externalbugtracker.py	2009-08-20 15:43:37 +0000
@@ -522,7 +522,9 @@
         # what BugZilla will return.
         local_time = xmlrpclib.DateTime(local_datetime.timetuple())
 
-        utc_date_time = local_datetime - timedelta(seconds=self.utc_offset)
+        utc_offset_delta = timedelta(seconds=self.utc_offset)
+        utc_date_time = local_datetime - utc_offset_delta
+
         utc_time = xmlrpclib.DateTime(utc_date_time.timetuple())
         return {
             'local_time': local_time,
@@ -757,7 +759,10 @@
 
     # Map namespaces onto method names.
     methods = {
-        'Bugzilla': ['version'],
+        'Bugzilla': [
+            'time',
+            'version',
+            ],
         'Test': ['login_required'],
         'User': ['login'],
         }
@@ -794,6 +799,24 @@
                     300,
                     "The username or password you entered is not valid.")
 
+    def time(self):
+        """Return a dict of the local time and associated data."""
+        # We cheat slightly by calling the superclass to get the time
+        # data. We do this the old fashioned way because XML-RPC
+        # Transports don't support new-style classes.
+        time_dict = TestBugzillaXMLRPCTransport.time(self)
+        offset_hours = (self.utc_offset / 60) / 60
+        offset_string = '+%02d00' % offset_hours
+
+        return {
+            'db_time': time_dict['local_time'],
+            'tz_name': time_dict['tz_name'],
+            'tz_offset': offset_string,
+            'tz_short_name': time_dict['tz_name'],
+            'web_time': time_dict['local_time'],
+            'web_time_utc': time_dict['utc_time'],
+            }
+
 
 class TestMantis(Mantis):
     """Mantis ExternalSystem for use in tests.