Isso can now listen on unix domain sockets, closes #25

This also changes the server configuration from `host` and `port`
to `listen = http://localhost:8080`.

docs/CONFIGURATION.rst

@@ -91,25 +91,36 @@ purge-after
 Server
 ------
 
-HTTP server configuration, does **not** apply to uWSGI (except for `profile`).
+HTTP server configuration.
 
 .. code-block:: ini
 
     [server]
-    host = localhost
-    port = 8080
+    listen = http://localhost:8080
     reload = off
     profile = off
 
-host
-    listen on specified interface
+listen
+    interface to listen on. Isso supports TCP/IP and unix domain sockets:
 
-port
-    application port
+    .. code-block:: uni
+
+        ; UNIX domain socket
+        listen = unix:///tmp/isso.sock
+        ; TCP/IP
+        listen = http:///localhost:1234/
+
+    When ``gevent`` is available, it is automatically used for `http://`
+    Currently, gevent can not handle http requests on unix domain socket
+    (see `#295 <https://github.com/surfly/gevent/issues/295>`_ and
+    `#299 <https://github.com/surfly/gevent/issues/299>`_ for details).
+
+    Does not apply for `uWSGI`.
 
 reload
     reload application, when the source code has changed. Useful for
-    development (don't forget to use a fixed `session-key`).
+    development (don't forget to use a fixed `session-key`). Only works
+    when ``gevent`` and ``uwsgi`` are *not* available.
 
 profile
     show 10 most time consuming function in Isso after each request. Do

isso/__init__.py

@@ -30,8 +30,14 @@ from __future__ import print_function
 import pkg_resources
 dist = pkg_resources.get_distribution("isso")
 
+try:
+    import gevent.monkey; gevent.monkey.patch_all()
+except ImportError:
+    pass
+
 import sys
 import os
+import socket
 import logging
 
 from os.path import dirname, join
@@ -46,11 +52,10 @@ import misaka
 from itsdangerous import URLSafeTimedSerializer
 
 from werkzeug.routing import Map, Rule
-from werkzeug.wrappers import Response
 from werkzeug.exceptions import HTTPException, InternalServerError
 
 from werkzeug.wsgi import SharedDataMiddleware
-from werkzeug.serving import run_simple
+from werkzeug.serving import run_simple, WSGIRequestHandler
 from werkzeug.contrib.fixers import ProxyFix
 
 from isso import db, migrate, views, wsgi
@@ -208,8 +213,52 @@ def main():
         migrate.disqus(db.SQLite3(conf.get('general', 'dbpath'), conf), args.dump)
         sys.exit(0)
 
-    run_simple(conf.get('server', 'host'), conf.getint('server', 'port'), make_app(conf),
-               threaded=True, use_reloader=conf.getboolean('server', 'reload'))
+    if conf.get("server", "listen").startswith("http://"):
+        host, port, _ = parse.host(conf.get("server", "listen"))
+        try:
+            from gevent.pywsgi import WSGIServer
+            WSGIServer((host, port), make_app(conf)).serve_forever()
+        except ImportError:
+            run_simple(host, port, make_app(conf), threaded=True,
+                       use_reloader=conf.getboolean('server', 'reload'))
+    else:
+        try:
+            from socketserver import ThreadingMixIn
+            from http.server import HTTPServer
+        except ImportError:
+            from SocketServer import ThreadingMixIn
+            from BaseHTTPServer import HTTPServer
+
+        class SocketWSGIRequestHandler(WSGIRequestHandler):
+
+            def run_wsgi(self):
+                self.client_address = ("<local>", 0)
+                super(SocketWSGIRequestHandler, self).run_wsgi()
+
+        class SocketHTTPServer(HTTPServer, ThreadingMixIn):
+
+            multithread = True
+            multiprocess = False
+
+            allow_reuse_address = 1
+            address_family = socket.AF_UNIX
+
+            request_queue_size = 128
+
+            def __init__(self, sock, app):
+                HTTPServer.__init__(self, sock, SocketWSGIRequestHandler)
+                self.app = app
+                self.ssl_context = None
+                self.shutdown_signal = False
+
+        sock = conf.get("server", "listen").partition("unix://")[2]
+
+        try:
+            os.unlink(sock)
+        except OSError:
+            pass
+
+        SocketHTTPServer(sock, make_app(conf)).serve_forever()
 
 try:
     import uwsgi

isso/core.py

@@ -92,7 +92,7 @@ class Config:
         "enabled = false",
         "purge-after = 30d",
         "[server]",
-        "host = localhost", "port = 8080",
+        "listen = http://localhost:8080/",
         "reload = off", "profile = off",
         "[smtp]",
         "username = ", "password = ",