general: add support for prometheus stats (#19766)

debian/control

@@ -14,7 +14,8 @@ Depends: ${misc:Depends},
     python-requests,
     python-raven,
     python-graypy,
-    python-apt
+    python-apt,
+    python-prometheus-client
 Recommends: python-django (>= 1.8),
     python-gadjo,
     python-django-mellon (>= 1.2.22.26),

debian/debian_config_common.py

@@ -304,6 +304,9 @@ MIDDLEWARE_CLASSES = (
     'hobo.middleware.xforwardedfor.XForwardedForMiddleware',
 ) + MIDDLEWARE_CLASSES
 
+MIDDLEWARE_CLASSES = MIDDLEWARE_CLASSES + (
+    'hobo.middleware.PrometheusStatsMiddleware',)
+
 HOBO_MANAGER_HOMEPAGE_URL_VAR = 'portal_agent_url'
 HOBO_MANAGER_HOMEPAGE_TITLE_VAR = 'portal_agent_title'
 

hobo/middleware/__init__.py

@@ -1,2 +1,3 @@
 from .version import VersionMiddleware
 from .cors import CORSMiddleware
+from .stats import PrometheusStatsMiddleware

hobo/middleware/stats.py

@@ -0,0 +1,106 @@
+# hobo - portal to configure and deploy applications
+# Copyright (C) 2017  Entr'ouvert
+#
+# This program is free software: you can redistribute it and/or modify it
+# under the terms of the GNU Affero General Public License as published
+# by the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import inspect
+import time
+
+import django
+from django.db import connection
+from django.http import HttpResponse
+
+import prometheus_client
+
+if django.VERSION >= (1, 10, 0):
+    from django.utils.deprecation import MiddlewareMixin
+else:
+    MiddlewareMixin = object
+
+
+requests_total_by_host_view_status_method = prometheus_client.Counter(
+    'django_http_requests_total_by_host_view_status_method',
+    'Count of requests by host, view, status, method.',
+    ['host', 'view', 'status', 'method'])
+
+requests_bytes_by_host_view_status_method = prometheus_client.Summary(
+    'django_http_requests_bytes_by_host_view_status_method',
+    'Bytes of requests by host, view, status, method.',
+    ['host', 'view', 'status', 'method'])
+
+requests_times_by_host_view_status_method = prometheus_client.Summary(
+    'django_http_requests_times_by_host_view_status_method',
+    'Duration of requests by host, view, status, method.',
+    ['host', 'view', 'status', 'method'])
+
+requests_queries_count_by_host_view_status_method = prometheus_client.Summary(
+    'django_http_requests_queries_count_by_host_view_status_method',
+    'Query count by host, view, status, method.',
+    ['host', 'view', 'status', 'method'])
+
+requests_queries_time_by_host_view_status_method = prometheus_client.Summary(
+    'django_http_requests_queries_time_by_host_view_status_method',
+    'Query time by host, view, status, method.',
+    ['host', 'view', 'status', 'method'])
+
+
+
+class PrometheusStatsMiddleware(MiddlewareMixin):
+    def process_request(self, request):
+        if request.method == 'GET' and request.path == '/__metrics__/':
+            return HttpResponse(prometheus_client.generate_latest(),
+                    content_type=prometheus_client.CONTENT_TYPE_LATEST)
+
+        connection.force_debug_cursor = True # to count queries
+        request._stats_t0 = time.time()
+        return None
+
+    def process_view(self, request, view_func, view_args, view_kwargs):
+        view = view_func
+        if not inspect.isfunction(view_func):
+            view = view.__class__
+        try:
+            request._view_name = '%s.%s' % (view.__module__, view.__name__)
+        except AttributeError:
+            pass
+
+    def process_response(self, request, response):
+        if not hasattr(request, '_stats_t0'):
+            return response
+        http_method = request.method
+        host_name = request.get_host()
+        total_time = time.time() - request._stats_t0
+
+        status_code = response.status_code
+        view_name = getattr(request, '_view_name', '<unnamed view>')
+        requests_total_by_host_view_status_method.labels(
+                host_name, view_name, status_code, http_method).inc()
+
+        if hasattr(response, 'content'):
+            response_size = len(response.content)
+            requests_bytes_by_host_view_status_method.labels(
+                    host_name, view_name, status_code, http_method).observe(response_size)
+
+        requests_times_by_host_view_status_method.labels(
+                host_name, view_name, status_code, http_method).observe(total_time)
+
+        if connection.queries_logged:
+            sql_queries_count = len(connection.queries)
+            sql_queries_time = sum([float(x['time']) for x in connection.queries])
+            requests_queries_count_by_host_view_status_method.labels(
+                    host_name, view_name, status_code, http_method).observe(sql_queries_count)
+            requests_queries_time_by_host_view_status_method.labels(
+                    host_name, view_name, status_code, http_method).observe(sql_queries_time)
+
+        return response

requirements.txt

@@ -2,3 +2,4 @@ django>=1.8,<1.9
 -e git+http://repos.entrouvert.org/gadjo.git/#egg=gadjo
 celery<4
 django-mellon
+prometheus_client

setup.py

@@ -100,6 +100,7 @@ setup(
         'celery<4',
         'django-mellon',
         'django-tenant-schemas',
+        'prometheus_client',
     ],
     zip_safe=False,
     cmdclass={