add debug option and support in paster. It allows us to work with paster

in debug mode and some other app that eval results. In debug mode only
one worker could be launch and wsgi.multiprocess is set to False.

gunicorn/arbiter.py

@@ -32,13 +32,14 @@ class Arbiter(object):
         if name[:3] == "SIG" and name[3] != "_"
     )
     
-    def __init__(self, address, num_workers, modname):
+    def __init__(self, address, num_workers, modname, debug=False):
         self.address = address
         self.num_workers = num_workers
         self.modname = modname
         self.timeout = 30
         self.reexec_pid = 0
         self.pid = os.getpid()
+        self.debug = debug
         self.log = logging.getLogger(__name__)
         self.init_signals()
         self.listen(self.address)
@@ -270,7 +271,7 @@ class Arbiter(object):
                 continue
 
             worker = Worker(i, self.pid, self.LISTENER, self.modname,
-                        self.timeout)
+                        self.timeout, self.debug)
             pid = os.fork()
             if pid != 0:
                 self.WORKERS[pid] = worker

gunicorn/http/request.py

@@ -43,7 +43,9 @@ class HttpRequest(object):
     }
 
 
-    def __init__(self, socket, client_address, server_address):
+    def __init__(self, socket, client_address, server_address, 
+            debug=False):
+        self.debug = debug
         self.socket = socket
         self.client_address = client_address
         self.server_address = server_address
@@ -82,13 +84,24 @@ class HttpRequest(object):
         else:
             wsgi_input = TeeInput(self.socket, self.parser, buf[i:])
                 
+                
+        if self.debug:
+            # according to the doc 
+            # This value should evaluate true if an equivalent application object
+            # may be simultaneously invoked by another process, and should evaluate
+            # false otherwise. In debug mode we fall to one worker
+            # so we comply to pylons and other paster app.
+            wsgi_multiprocess = False
+        else:
+            wsgi_multiprocess = True
+            
         environ = {
             "wsgi.url_scheme": 'http',
             "wsgi.input": wsgi_input,
             "wsgi.errors": sys.stderr,
             "wsgi.version": (1, 0),
             "wsgi.multithread": False,
-            "wsgi.multiprocess": True,
+            "wsgi.multiprocess": wsgi_multiprocess,
             "wsgi.run_once": False,
             "SCRIPT_NAME": "",
             "SERVER_SOFTWARE": self.SERVER_VERSION,

gunicorn/main.py

@@ -28,7 +28,9 @@ def options():
         op.make_option('--log-level', dest='loglevel', default='info',
             help='Log level below which to silence messages. [%default]'),
         op.make_option('--log-file', dest='logfile', default='-',
-            help='Log to a file. - is stdout. [%default]')
+            help='Log to a file. - is stdout. [%default]'),
+        op.make_option('-d', '--debug', dest='debug', action="store_true",
+            default=False, help='Debug mode. only 1 worker.')
     ]
 
 def configure_logging(opts):
@@ -52,7 +54,12 @@ def main(usage, get_app):
     configure_logging(opts)
 
     app = get_app(parser, opts, args)
-    arbiter = Arbiter((opts.host, opts.port), opts.workers, app)
+    workers = opts.workers
+    if opts.debug:
+        workers = 1
+    
+    arbiter = Arbiter((opts.host, opts.port), workers, app, 
+                    opts.debug)
     arbiter.run()
     
 def paste_server(app, global_conf=None, host="127.0.0.1", port=None, 
@@ -69,5 +76,11 @@ def paste_server(app, global_conf=None, host="127.0.0.1", port=None,
     else:
         workers = int(global_conf.get('workers', 1))
     
-    arbiter = Arbiter(bind_addr, workers, app)
+    debug = global_conf.get('debug') == "true"
+    if debug:
+        # we force to one worker in debug mode.
+        workers = 1
+    
+    arbiter = Arbiter(bind_addr, workers, app, 
+                    debug)
     arbiter.run()

gunicorn/worker.py

@@ -25,9 +25,11 @@ class Worker(object):
         "HUP QUIT INT TERM TTIN TTOU USR1".split()
     )
 
-    def __init__(self, workerid, ppid, socket, app, timeout):
+    def __init__(self, workerid, ppid, socket, app, timeout,
+            debug=False):
         self.id = workerid
         self.ppid = ppid
+        self.debug = debug
         self.timeout = timeout / 2.0
         fd, tmpname = tempfile.mkstemp()
         self.tmp = os.fdopen(fd, "r+b")
@@ -115,7 +117,7 @@ class Worker(object):
     def handle(self, client, addr):
         util.close_on_exec(client)
         try:
-            req = http.HttpRequest(client, addr, self.address)
+            req = http.HttpRequest(client, addr, self.address, self.debug)
             try:
                 response = self.app(req.read(), req.start_response)
             except Exception, e:

setup.py

@@ -45,5 +45,4 @@ setup(
     main=gunicorn.main:paste_server
     """,
     test_suite = 'nose.collector',
-)
-
+)