Improved exception handling

openedx_webhooks/tasks/pr_tracking.py

@@ -4,6 +4,7 @@
 
 from __future__ import annotations
 
+import contextlib
 import copy
 import dataclasses
 import itertools
@@ -227,6 +228,10 @@
     label_names = set(lbl["name"] for lbl in pr["labels"])
     desired.jira_nicks = {name.partition(":")[-1] for name in label_names if name.startswith("jira:")}
 
+    if "crash!123" in label_names:
+        # Low-tech backdoor way to test error handling and reporting.
+        raise Exception(f"A crash label was applied by {user}")
+
     desired.jira_title = pr["title"]
     desired.jira_description = pr["body"] or ""
 
@@ -314,10 +319,23 @@
 
         self.bot_data = copy.deepcopy(current.bot_data)
         self.fix_result: FixResult = FixResult()
+        self.exceptions: List[Exception] = []
 
     def result(self) -> FixResult:
         return self.fix_result
 
+    @contextlib.contextmanager
+    def saved_exceptions(self):
+        """
+        A context manager to wrap around isolatable steps.
+
+        An exception raised in the with-block will be added to `self.exceptions`.
+        """
+        try:
+            yield
+        except Exception as exc:
+            self.exceptions.append(exc)
+
     def fix(self) -> None:
         """
         The main routine for making needed changes.
@@ -331,19 +349,26 @@
 
         if self.desired.cla_check != self.current.cla_check:
             assert self.desired.cla_check is not None
-            self.actions.set_cla_status(status=self.desired.cla_check)
+            with self.saved_exceptions():
+                self.actions.set_cla_status(status=self.desired.cla_check)
 
         if self.desired.is_ospr:
-            self._fix_ospr()
+            with self.saved_exceptions():
+                self._fix_ospr()
 
         if self.desired.is_refused:
-            self._fix_comments()
+            with self.saved_exceptions():
+                self._fix_comments()
 
         # Make needed Jira issues.
         current_jira_nicks = {ji.nick for ji in self.current.bot_data.jira_issues}
         for jira_nick in self.desired.jira_nicks:
             if jira_nick not in current_jira_nicks:
-                self._make_jira_issue(jira_nick)
+                with self.saved_exceptions():
+                    self._make_jira_issue(jira_nick)
+
+        if self.exceptions:
+            raise ExceptionGroup("Some actions failed", self.exceptions)
 
     def _fix_comments(self) -> None:
         fix_comment = True

openedx_webhooks/templates/main.html

@@ -31,8 +31,8 @@ <h2>GitHub</h2>
 
     <h2>Other</h2>
     <ul>
-      <li><a href="{{ url_for("github_views.generate_error") }}">Generate Immediate Error</a></li>
-      <li><a href="{{ url_for("github_views.generate_task_error") }}">Generate Task Error</a></li>
+      <li><a href="{{ url_for("github_views.generate_error") }}">Generate Immediate Flask Error</a></li>
+      <li><a href="{{ url_for("github_views.generate_task_error") }}">Generate Celery Task Error</a></li>
     </ul>
     </body>
 </html>

tests/test_pull_request_opened.py

@@ -334,6 +334,13 @@ def test_add_to_multiple_projects(fake_github):
     }
 
 
+def test_crash_label(fake_github):
+    pr = fake_github.make_pull_request("openedx", user="nedbat")
+    pr.set_labels(["crash!123"])
+    with pytest.raises(Exception, match="A crash label was applied by nedbat"):
+        pull_request_changed(pr.as_json())
+
+
 def test_jira_labelling(fake_github, fake_jira, fake_jira2):
     # A PR with a "jira:" label makes a Jira issue.
     pr = fake_github.make_pull_request("openedx", user="nedbat", title="Ned's PR")