Example about how to kill a running task

readthedocs/builds/models.py

@@ -687,6 +687,12 @@ class Build(models.Model):
         _('Cold Storage'),
         help_text='Build steps stored outside the database.',
     )
+    task_id = models.CharField(
+        _('Celery task id'),
+        max_length=36,
+        null=True,
+        blank=True,
+    )
 
     # Managers
     objects = BuildManager.from_queryset(BuildQuerySet)()

readthedocs/builds/views.py

@@ -153,3 +153,19 @@ def get_context_data(self, **kwargs):
         issue_url = urlparse(issue_url).geturl()
         context['issue_url'] = issue_url
         return context
+
+    @method_decorator(login_required)
+    def post(self, request, project_slug, build_pk):
+        project = get_object_or_404(Project, slug=project_slug)
+        build = get_object_or_404(Build, pk=build_pk)
+
+        if not AdminPermission.is_admin(request.user, project):
+            return HttpResponseForbidden()
+
+        import signal
+        from celery.task.control import revoke
+        revoke(build.task_id, signal=signal.SIGINT, terminate=True)
+
+        return HttpResponseRedirect(
+            reverse('builds_detail', args=[project.slug, build.pk]),
+        )

readthedocs/core/utils/__init__.py

@@ -225,7 +225,10 @@ def trigger_build(project, version=None, commit=None, record=True, force=False):
         # Build was skipped
         return (None, None)
 
-    return (update_docs_task.apply_async(), build)
+    task = update_docs_task.apply_async()
+    build.task_id = task.id
+    build.save()
+    return task, build
 
 
 def send_email(

readthedocs/doc_builder/environments.py

@@ -50,6 +50,7 @@
     ProjectBuildsSkippedError,
     VersionLockedError,
     YAMLParseError,
+    BuildKilled,
 )
 
 
@@ -356,7 +357,7 @@ def run(self):
                         '\n\nCommand killed due to excessive memory consumption\n',
                     ),
                 )
-        except DockerAPIError:
+        except (DockerAPIError, BuildKilled):
             self.exit_code = -1
             if self.output is None or not self.output:
                 self.output = _('Command exited abnormally')
@@ -605,6 +606,13 @@ def handle_exception(self, exc_type, exc_value, _):
             elif exc_type in self.WARNING_EXCEPTIONS:
                 log_level_function = log.warning
                 self.failure = exc_value
+            elif exc_type is BuildKilled:
+                log.warning('KILLED FROM handle_exception')
+                log_level_function = log.warning
+                self.failure = 'Killed!'
+                self.build['state'] = BUILD_STATE_FINISHED
+                # self.done = True
+                # self.successful = False
             else:
                 log_level_function = log.error
                 self.failure = exc_value

readthedocs/doc_builder/exceptions.py

@@ -90,3 +90,7 @@ class MkDocsYAMLParseError(BuildEnvironmentError):
         'Please follow the user guide https://www.mkdocs.org/user-guide/configuration/ '
         'to configure the file properly.',
     )
+
+
+class BuildKilled(Exception):
+    pass

readthedocs/projects/tasks.py

@@ -64,6 +64,7 @@
     ProjectBuildsSkippedError,
     VersionLockedError,
     YAMLParseError,
+    BuildKilled,
 )
 from readthedocs.doc_builder.loader import get_builder_class
 from readthedocs.doc_builder.python_environments import Conda, Virtualenv
@@ -536,7 +537,32 @@ def run(
 
         :rtype: bool
         """
+
         try:
+            def sigstop_received(*args, **kwargs):
+                log.warning('SIGSTOP received. Killing the current building.')
+                env_cls = DockerBuildEnvironment
+                # environment = env_cls(
+                #     project=self.project,
+                #     version=self.version,
+                #     build=self.build,
+                #     record=False,
+                #     update_on_success=False,
+                # )
+                # client = environment.get_client()
+                # client.kill(environment.container_id)
+                # client.remove_container(environment.container_id)
+                # api_v2.build(self.build['id']).patch({
+                #     'error': 'Killed!',
+                #     'success': False,
+                #     'state': BUILD_STATE_FINISHED,
+                # })
+                raise BuildKilled
+                return False
+
+            # signal.signal(signal.SIGUSR2, sigstop_received)
+            signal.signal(signal.SIGINT, sigstop_received)
+
             self.version = self.get_version(version_pk)
             self.project = self.version.project
             self.build = self.get_build(build_pk)
@@ -585,6 +611,19 @@ def run(
                 return False
             self.run_build(record=record)
             return True
+        except BuildKilled:
+            log.warning(
+                'Build killed by user. project=%s version=%s build=%s',
+                self.project.slug,
+                self.version.slug,
+                build_pk,
+            )
+            api_v2.build(self.build['id']).patch({
+                'error': 'Killed!',
+                'success': False,
+                'state': BUILD_STATE_FINISHED,
+            })
+            return False
         except Exception:
             log.exception(
                 'An unhandled exception was raised during build setup',

readthedocs/templates/builds/build_detail.html

@@ -30,6 +30,12 @@
 {% block content %}
   <div class="build build-detail" id="build-detail">
 
+    <form method="post" action="{% url "builds_detail" build.version.project.slug build.pk %}">
+        {% csrf_token %}
+        <input type="submit" value="{% trans "Cancel build" %}">
+    </form>
+
+
     <!-- Build meta data -->
     <ul class="build-meta">
       <div data-bind="visible: finished()">