From 9e28476a0eabf18f159798d46293c1910766a916 Mon Sep 17 00:00:00 2001
From: Matthew Betts <matt@publons.com>
Date: Mon, 18 Nov 2019 14:08:12 +1100
Subject: [PATCH] Add django middleware to write flamegraphs for requests to
 files

---
 flame_analyzer/middleware.py | 37 ++++++++++++++++++++++++++++++++++++
 1 file changed, 37 insertions(+)
 create mode 100644 flame_analyzer/middleware.py

diff --git a/flame_analyzer/middleware.py b/flame_analyzer/middleware.py
new file mode 100644
index 0000000..889c7d1
--- /dev/null
+++ b/flame_analyzer/middleware.py
@@ -0,0 +1,37 @@
+from datetime import datetime
+
+from flame_analyzer import DjangoFileFlame
+
+try:
+    from django.utils.deprecation import MiddlewareMixin
+
+    class FlameMiddleware(MiddlewareMixin):
+        """
+        Django Middleware to log flamegraphs to files.
+        Requires python manager.py runserver --noreload --nothreading
+        """
+
+        def __call__(self, request):
+            self.process_request()
+            response = self.get_response(request)
+            return self.process_response(request, response)
+
+        def process_request(self, request):
+            request.flame = DjangoFileFlame(self.file_path(request))
+            request.flame.__enter__()
+
+        def process_response(self, request, response):
+            if hasattr(request, 'flame'):
+                request.flame.__exit__(None, None, None)
+            return response
+
+        def file_path(self, request):
+            now = datetime.now().strftime(f'%Y-%m-%d-%H:%M:%S')
+            path = request.get_full_path().strip('/')
+            file_path = f'{now}|{path}'.replace('/', '-')
+            file_path += '.svg'
+            return file_path
+
+
+except ImportError:
+    FlameMiddleware = None