fix issue #348 .

Rather than testing the parent pd, test if the parent pid is still
alive. Only use it in gevent for now.

examples/frameworks/django/testing/testing/apps/someapp/middleware.py

@@ -0,0 +1,22 @@
+from multiprocessing import Process, Queue
+import requests
+
+def child_process(queue):
+    while True:
+        print queue.get()
+        r = requests.get('http://friendpaste.com')
+        print r.headers
+
+class GunicornSubProcessTestMiddleware(object):
+    def __init__(self):
+        super(GunicornSubProcessTestMiddleware, self).__init__()
+        self.queue = Queue()
+        self.process = Process(target=child_process, args=(self.queue,))
+        self.process.start()
+
+    def process_request(self, request):
+        self.queue.put(('REQUEST',))
+
+    def process_response(self, request, response):
+        self.queue.put(('RESPONSE',response.status_code))
+        return response

examples/frameworks/django/testing/testing/settings.py

@@ -98,6 +98,7 @@ MIDDLEWARE_CLASSES = (
     'django.contrib.messages.middleware.MessageMiddleware',
     # Uncomment the next line for simple clickjacking protection:
     # 'django.middleware.clickjacking.XFrameOptionsMiddleware',
+    'testing.apps.someapp.middleware.GunicornSubProcessTestMiddleware'
 )
 
 ROOT_URLCONF = 'testing.urls'

gunicorn/util.py

@@ -353,3 +353,10 @@ def check_is_writeable(path):
     except IOError, e:
         raise RuntimeError("Error: '%s' isn't writable [%r]" % (path, e))
     f.close()
+
+def is_process_running(process_id):
+    try:
+        os.kill(process_id, 0)
+        return True
+    except OSError:
+        return False

gunicorn/workers/ggevent.py

@@ -23,6 +23,7 @@ from gevent import pywsgi
 
 import gunicorn
 from gunicorn.workers.async import AsyncWorker
+from gunicorn.util import is_process_running
 
 VERSION = "gevent/%s gunicorn/%s" % (gevent.__version__, gunicorn.__version__)
 
@@ -36,6 +37,7 @@ BASE_WSGI_ENV = {
     'wsgi.run_once': False
 }
 
+
 class GeventWorker(AsyncWorker):
 
     server_class = None
@@ -61,11 +63,12 @@ class GeventWorker(AsyncWorker):
         else:
             server = StreamServer(self.socket, handle=self.handle, spawn=pool)
 
-        server.start()
+        gevent.spawn(server.start)
         try:
             while self.alive:
                 self.notify()
-                if self.ppid != os.getppid():
+
+                if not is_process_running(self.ppid):
                     self.log.info("Parent changed, shutting down: %s", self)
                     break