ReviewBot: rework override check to operate on actions.

In multi-action workflows the override check should be performed by
action so that different groups of users can override for different
actions. Additionally, abstracting the request_commands() method provides
a flexible base for additional commands to be added by ReviewBots.

ReviewBot.py

@@ -182,10 +182,6 @@ class ReviewBot(object):
             with sentry_sdk.configure_scope() as scope:
                 scope.set_extra('request.id', self.request.reqid)
 
-            override = self.request_override_check(req)
-            if override is not None:
-                good = override
-            else:
             try:
                 good = self.check_one_request(req)
             except Exception as e:
@@ -228,15 +224,12 @@ class ReviewBot(object):
 
         return users
 
-    def request_override_check(self, request, force=False):
+    def request_override_check(self, force=False):
         """Check for a comment command requesting review override."""
         if not force and not self.override_allow:
             return None
 
-        comments = self.comment_api.get_comments(request_id=request.reqid)
-        users = self.request_override_check_users(request.actions[0].tgt_project)
-        for args, who in self.comment_api.command_find(
-            comments, self.review_user, 'override', users):
+        for args, who in self.request_commands('override'):
             message = 'overridden by {}'.format(who)
             override = args[1] if len(args) >= 2 else 'accept'
             if override == 'accept':
@@ -247,6 +240,17 @@ class ReviewBot(object):
                 self.review_messages['declined'] = message
                 return False
 
+    def request_commands(self, command, who_allowed=None, request=None, action=None):
+        if not request:
+            request = self.request
+        if not action:
+            action = self.action
+        if not who_allowed:
+            who_allowed = self.request_override_check_users(action.tgt_project)
+
+        comments = self.comment_api.get_comments(request_id=request.reqid)
+        yield from self.comment_api.command_find(comments, self.review_user, command, who_allowed)
+
     def _set_review(self, req, state):
         doit = self.can_accept_review(req.reqid)
         if doit is None:
@@ -407,6 +411,10 @@ class ReviewBot(object):
             with sentry_sdk.configure_scope() as scope:
                 scope.set_extra('action.key', key)
 
+            override = self.request_override_check()
+            if override is not None:
+                ret = override
+            else:
                 func = getattr(self, self.action_method(a))
                 ret = func(req, a)
 

origin-manager.py

@@ -86,7 +86,7 @@ class OriginManager(ReviewBot.ReviewBot):
         if result.wait:
             # Allow overriding a policy wait by accepting as workaround with the
             # hope that pending request will be accepted.
-            override = self.request_override_check(self.request, True)
+            override = self.request_override_check(True)
             if override:
                 self.review_messages['accepted'] = origin_annotation_dump(
                     origin_info_new, origin_info_old, self.review_messages['accepted'], raw=True)