Merge lp:~mars/tarmac/more-logging into lp:tarmac

[Māris Fogels]

Added additional debug logging to the authenticate and merge commands.

Hi,

This branch adds additional debug logging to the authenticate and merge commands.

With this patch users can run the 'tarmac merge --debug' command to see what the
program decides to do with the branches it finds, and why it decided to do it.
This solves a problem where new users may not understand why Tarmac is not
finding their branches. They later discover that the program silently skipped
their branches because the Launchpad commit message was not set. (This has
happened to me twice now, on two different Tarmac setups.)

I added the authentication logging to solve a problem with launchpadlib on
headless servers: the 'tarmac authenticate' command was not writing any log
output, and the launchpadlib commands were also failing - I did not know what
the program was doing. The additional logging makes it a bit easier to
understand that the call to launchpadlib is the problem.

[Paul Hummer (rockstar)]

This looks great. I'm actually wanting to move in a direction similar to what you did with _get_mergable_proposals_for_branch anyway, so this is a good start. Thanks for the patch!

review: Approve

=== modified file 'tarmac/bin/commands.py'
--- tarmac/bin/commands.py	2010-10-26 19:00:23 +0000
+++ tarmac/bin/commands.py	2010-10-29 22:17:41 +0000
@@ -66,15 +66,29 @@
         else:
             SERVICE_ROOT = EDGE_SERVICE_ROOT
 
+        self.logger.debug(
+            "Connecting to the Launchpad API at {0}".format(SERVICE_ROOT))
+
+        self.logger.debug("  Loading credentials from {0}".format(filename))
         if not os.path.exists(filename):
+            self.logger.debug("  No existing API credentials were found")
+            self.logger.debug("  Fetching new credentials from {0}".format(
+                SERVICE_ROOT))
+
             launchpad = Launchpad.get_token_and_login(
                 'Tarmac', SERVICE_ROOT, self.config.CACHE_HOME)
             launchpad.credentials.save(file(filename, 'w'))
+
+            self.logger.debug("  Credentials saved to {0}".format(filename))
         else:
             credentials = Credentials()
             credentials.load(open(filename))
+            self.logger.debug("  Credentials loaded".format(filename))
+
             launchpad = Launchpad(
                 credentials, SERVICE_ROOT, self.config.CACHE_HOME)
+
+        self.logger.debug("Connected")
         return launchpad
 
 
@@ -136,9 +150,9 @@
 
         lp_branch = self.launchpad.branches.getByUrl(url=branch_url)
 
-        proposals = [entry for entry in lp_branch.landing_candidates
-                        if entry.queue_status == u'Approved' and
-                        (imply_commit_message or entry.commit_message)]
+        proposals = self._get_mergable_proposals_for_branch(
+            lp_branch, imply_commit_message)
+
         if not proposals:
             self.logger.info(
                 'No approved proposals found for %(branch_url)s' % {
@@ -276,6 +290,27 @@
         finally:
             target.cleanup()
 
+    def _get_mergable_proposals_for_branch(self, lp_branch,
+                                           imply_commit_message):
+        """Return a list of the mergable proposals for the given branch."""
+        proposals = []
+        for entry in lp_branch.landing_candidates:
+            self.logger.debug("Considering merge proposal: {0}".format(entry))
+
+            if entry.queue_status != u'Approved':
+                self.logger.debug(
+                    "  Skipping proposal: status is {0}, not "
+                    "'Approved'".format(entry.queue_status))
+                continue
+
+            if not imply_commit_message and not entry.commit_message:
+                self.logger.debug(
+                    "  Skipping proposal: proposal has no commit message")
+                continue
+
+            proposals.append(entry)
+        return proposals
+
     def _get_reviews(self, proposal):
         """Get the set of reviews from the proposal."""
         reviews = []