@@ -18,10 +18,13 @@
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
from collections import OrderedDict
+import json
from rest_framework.generics import ListAPIView
from rest_framework.serializers import ModelSerializer
from rest_framework.serializers import SerializerMethodField
+from rest_framework.renderers import JSONRenderer
+from rest_framework.renderers import TemplateHTMLRenderer
from patchwork.api.embedded import CheckSerializer
from patchwork.api.embedded import CoverLetterSerializer
@@ -85,9 +88,21 @@ class EventSerializer(ModelSerializer):
read_only_fields = fields
+# The standard template html renderer is broken:
+# https://github.com/encode/django-rest-framework/issues/5236
+class JSONListHTMLRenderer(TemplateHTMLRenderer):
+ def get_template_context(self, data, renderer_context):
+ response = renderer_context['response']
+ if response.exception:
+ data['status_code'] = response.status_code
+ return {'data': json.dumps(data, indent=4)}
+
+
class EventList(ListAPIView):
"""List events."""
+ renderer_classes = (JSONRenderer, JSONListHTMLRenderer)
+ template_name = 'patchwork/event-list.html'
serializer_class = EventSerializer
filter_class = EventFilter
page_size_query_param = None # fixed page size
new file mode 100644
@@ -0,0 +1,17 @@
+{% extends "base.html" %}
+
+{% load person %}
+{% load static %}
+
+{% block title %}Event List{% endblock %}
+{% block patch_active %}active{% endblock %}
+
+{% block body %}
+
+<p>Due to a currently undiagnosed issue with django-rest-framework, the browsable API is very CPU intensive and has been disabled. The JSON output is:</p>
+
+<pre>
+{{data}}
+</pre>
+
+{% endblock %}
Something is very, very slow in the d-r-f browsable API events renderer. In my MySQL test (~33k patches), the CPU time to render the events list is ~11s, and the time taken by SQL queries is only ~3s. If the JSON renderer is used, that drops to 0.2s for the entire page (because less CPU is used, and - for some as yet unknown reason - a *very* expensive db query is dropped.) In my PostgreSQL test (~100k patches), the results are even more stark: 30s of CPU time and 0.2s of DB time goes to 0.25s for the entire page. Something is seriously, seriously wrong with whatever d-r-f is doing. So, simply render the event list as HTML-ised, unlinked JSON for now. There are a few followups we should do, but this is an important start - no-one should be able to DoS a patchwork server by just enumerating the events! In particular, we should find out: - why postgres and mysql behaviour is so different. - what on earth d-r-f is doing that makes rendering the pretty-printed version so incredibly slow. Signed-off-by: Daniel Axtens <dja@axtens.net> --- v2: Make it a bit nicer than just pure json. --- patchwork/api/event.py | 15 +++++++++++++++ patchwork/templates/patchwork/event-list.html | 17 +++++++++++++++++ 2 files changed, 32 insertions(+) create mode 100644 patchwork/templates/patchwork/event-list.html