Add profiling utilities

src/pretix/helpers/profile/middleware.py

@@ -0,0 +1,38 @@
+import cProfile
+import os
+import random
+
+import time
+from django.conf import settings
+
+
+class CProfileMiddleware(object):
+    blacklist = (
+        '/healthcheck/',
+        '/jsi18n/'
+    )
+
+    def __init__(self, get_response):
+        self.get_response = get_response
+        # One-time configuration and initialization.
+
+    def __call__(self, request):
+        # Code to be executed for each request before
+        # the view (and later middleware) are called.
+        for b in self.blacklist:
+            if b in request.path:
+                return self.get_response(request)
+
+        if settings.PROFILING_RATE > 0 and random.random() < settings.PROFILING_RATE / 100:
+            profiler = cProfile.Profile()
+            profiler.enable()
+            starttime = time.time()
+            response = self.get_response(request)
+            profiler.disable()
+            tottime = time.time() - starttime
+            profiler.dump_stats(os.path.join(settings.PROFILE_DIR, '{time:.0f}_{tottime:.3f}_{path}.pstat'.format(
+                path=request.path[1:].replace("/", "_"), tottime=tottime, time=time.time()
+            )))
+            return response
+        else:
+            return self.get_response(request)

src/pretix/settings.py

@@ -16,6 +16,7 @@ BASE_DIR = os.path.dirname(os.path.dirname(__file__))
 DATA_DIR = config.get('pretix', 'datadir', fallback=os.environ.get('DATA_DIR', 'data'))
 LOG_DIR = os.path.join(DATA_DIR, 'logs')
 MEDIA_ROOT = os.path.join(DATA_DIR, 'media')
+PROFILE_DIR = os.path.join(DATA_DIR, 'profiles')
 
 if not os.path.exists(DATA_DIR):
     os.mkdir(DATA_DIR)
@@ -223,6 +224,14 @@ try:
 except ImportError:
     pass
 
+
+PROFILING_RATE = config.getfloat('django', 'profile', fallback=0)  # Percentage of requests to profile
+if PROFILING_RATE > 0:
+    if not os.path.exists(PROFILE_DIR):
+        os.mkdir(PROFILE_DIR)
+    MIDDLEWARE.insert(0, 'pretix.helpers.profile.middleware.CProfileMiddleware')
+
+
 # Security settings
 X_FRAME_OPTIONS = 'DENY'