[FIX] runbot_merge: make staging cancels more greppable

I just spent 10mn trying to find out why staging 28 was cancelled
(a p=0 comment). Add a common prefix to all staging cancels to make
them easier to find.

runbot_merge/controllers/__init__.py

@@ -153,9 +153,9 @@ def handle_pr(env, event):
 
         if pr_obj.state == 'ready':
             pr_obj.staging_id.cancel(
-                "Updated PR %s:%s, removing staging %s",
+                "PR %s:%s updated by %s",
                 pr_obj.repository.name, pr_obj.number,
-                pr_obj.staging_id,
+                event['sender']['login']
             )
         if pr_obj.state != 'error':
             pr_obj.state = 'opened'
@@ -168,9 +168,9 @@ def handle_pr(env, event):
     if event['action'] == 'closed' and pr_obj.state != 'merged':
         pr_obj.state = 'closed'
         pr_obj.staging_id.cancel(
-            "Closed PR %s:%s, removing staging %s",
+            "PR %s:%s closed by %s",
             pr_obj.repository.name, pr_obj.number,
-            pr_obj.staging_id
+            event['sender']['login']
         )
         return 'Closed {}'.format(pr_obj.id)
 

runbot_merge/models/pull_requests.py

@@ -564,7 +564,7 @@ class PullRequests(models.Model):
                     self.priority = param
                     if param == 0:
                         self.target.active_staging_id.cancel(
-                            "P=0 on %s:%s by %s, unstaging %s",
+                            "P=0 on %s:%s by %s, unstaging target %s",
                             self.repository.name, self.number,
                             author.github_login, self.target.name,
                         )
@@ -821,7 +821,7 @@ class Stagings(models.Model):
         if not self:
             return
 
-        _logger.info(reason, *args)
+        _logger.info("Cancelling staging %s: " + reason, self, *args)
         self.batch_ids.write({'active': False})
         self.active = False
 

runbot_merge/tests/fake_github/__init__.py

@@ -702,6 +702,7 @@ class Client(werkzeug.test.Client):
                 'action': action,
                 'pull_request': self._pr(pr),
                 'repository': self._repo(pr.repo.name),
+                'sender': {'login': '<>'},
                 **({'changes': changes} if changes else {})
             }
         ))