Merge ~shawn111/pmr:one-shot into pmr:master

[Shawn Wang]

[Colin Watson (cjwatson)]

The requirement I've seen for --one-shot comes from Jenkaas, and my understanding is that in that context the requirement would be more precisely described as an option that causes pmr to land at most one merge request. This doesn't meet that requirement.

Could you push the check down into the loop in merge_mergable_on_project instead? I'd suggest that the option description should then become something like "Only check for approved merge requests once, and land at most one of them."

review: Needs Fixing

[Shawn Wang (shawn111)]

Hi Colin,

Yes, you are right, I should move the --one-shot option into merge_mergable_on_project.
And yes, it is for Jenkaas.

I also improve the check for project_list with parser.error.

Could you help me review it again?

Thanks,
Shawn

[Colin Watson (cjwatson)]

Looks fine now, thanks, just a few style tweaks.

review: Approve

diff --git a/process-merge-requests b/process-merge-requests
index 02b59a6..9f6b561 100755
--- a/process-merge-requests
+++ b/process-merge-requests
@@ -258,7 +258,7 @@ def merge_bzr_proposal(branch_merge_proposal):
     _logger.info(_("Bzr merge completed"))
 
 
-def merge_mergable_on_project(project):
+def merge_mergable_on_project(project, one_shot=False):
     """Merge all approved merge requests on a given project."""
     _logger.debug("Inspecting merge requests on project: %s", project.web_link)
     num_seen = 0
@@ -278,6 +278,9 @@ def merge_mergable_on_project(project):
         else:
             assert branch_merge_proposal.target_git_repository_link is None
             merge_bzr_proposal(branch_merge_proposal)
+        if one_shot:
+            _logger.info(_("Only landing one request in one-shot mode."))
+            return
     if num_seen == 0:
         _logger.debug(_("There are no merge proposals present at this time"))
 
@@ -310,19 +313,35 @@ def main():
     parser.add_argument(
         'project_list', metavar=_('PROJECT'), nargs="+",
         help=_("name of the launchpad project to process"))
+    parser.add_argument(
+        "--one-shot", action='store_true', default=False,
+        help=_("Only check for approved merge requests once, "
+               "and land at most one of them."))
     ns = parser.parse_args()
     _logger.info(_("Logging into launchpad.net"))
     lp = Launchpad.login_with('process-merge-requests', ns.lp_api_url)
+
+    projects = []
+    for project_name in ns.project_list:
+        try:
+            project = lp.projects[project_name]
+        except KeyError:
+            raise parser.error(
+                "No such project: %s" % project_name)
+        projects.append(project)
+
+    if ns.one_shot:
+        if len(ns.project_list) > 1:
+            raise parser.error(
+                "The --one-shot option may only be used with a single project.")
+        merge_mergable_on_project(projects[0], one_shot=True)
+        return
+
     _logger.info(_("Checking for new things to land every minute..."))
     try:
         while True:
-            for project_name in ns.project_list:
-                try:
-                    project = lp.projects[project_name]
-                except KeyError:
-                    _logger.error(_("No such project: %s"), project_name)
-                else:
-                    merge_mergable_on_project(project)
+            for project in projects:
+                merge_mergable_on_project(project)
             time.sleep(60)
     except KeyboardInterrupt:
         pass