Add an embedded HTTP server to Supybot.

scripts/supybot

@@ -121,6 +121,7 @@ def main():
                 print 'raise an exception, but freaking-a, it was a string'
                 print 'exception.  People who raise string exceptions should'
                 print 'die a slow, painful death.'
+    httpserver.stopServer()
     now = time.time()
     seconds = now - world.startedAt
     log.info('Total uptime: %s.', utils.gen.timeElapsed(seconds))
@@ -331,6 +332,10 @@ if __name__ == '__main__':
 
     owner = Owner.Class()
 
+    # These may take some resources, and it does not need to be run while boot, so
+    # we import it as late as possible.
+    import supybot.utils.httpserver as httpserver
+
     if options.profile:
         import profile
         world.profiling = True

src/conf.py

@@ -1042,13 +1042,10 @@ utils.web.proxy = supybot.protocols.http.proxy
 
 
 ###
-# Especially boring stuff.
+# HTTP server
 ###
-registerGlobalValue(supybot, 'defaultIgnore',
-    registry.Boolean(False, _("""Determines whether the bot will ignore
-    unregistered users by default.  Of course, that'll make it particularly
-    hard for those users to register or identify with the bot, but that's your
-    problem to solve.""")))
+registerGroup(supybot, 'servers')
+registerGroup(supybot.servers, 'http')
 
 class IP(registry.String):
     """Value must be a valid IP."""
@@ -1058,6 +1055,27 @@ class IP(registry.String):
         else:
             registry.String.setValue(self, v)
 
+registerGlobalValue(supybot.servers.http, 'host',
+    IP('0.0.0.0', _("Determines what host the HTTP server will bind.")))
+registerGlobalValue(supybot.servers.http, 'port',
+    registry.Integer(8080, _("""Determines what port the HTTP server will
+    bind.""")))
+registerGlobalValue(supybot.servers.http, 'keepAlive',
+    registry.Boolean(True, _("""Defines whether the server will stay alive if
+    no plugin is using it. This also means that the server will start even
+    if it is not used.""")))
+
+
+###
+# Especially boring stuff.
+###
+registerGlobalValue(supybot, 'defaultIgnore',
+    registry.Boolean(False, _("""Determines whether the bot will ignore
+    unregistered users by default.  Of course, that'll make it particularly
+    hard for those users to register or identify with the bot, but that's your
+    problem to solve.""")))
+
+
 registerGlobalValue(supybot, 'externalIP',
    IP('', _("""A string that is the external IP of the bot.  If this is the
    empty string, the bot will attempt to find out its IP dynamically (though

src/utils/httpserver.py

@@ -0,0 +1,197 @@
+###
+# Copyright (c) 2011, Valentin Lorentz
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+#
+#   * Redistributions of source code must retain the above copyright notice,
+#     this list of conditions, and the following disclaimer.
+#   * Redistributions in binary form must reproduce the above copyright notice,
+#     this list of conditions, and the following disclaimer in the
+#     documentation and/or other materials provided with the distribution.
+#   * Neither the name of the author of this software nor the name of
+#     contributors to this software may be used to endorse or promote products
+#     derived from this software without specific prior written consent.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.
+###
+
+"""
+An embedded and centralized HTTP server for Supybot's plugins.
+"""
+
+from threading import Event, Thread
+from cStringIO import StringIO
+from SocketServer import ThreadingMixIn
+from BaseHTTPServer import HTTPServer, BaseHTTPRequestHandler
+
+import supybot.log as log
+import supybot.conf as conf
+import supybot.world as world
+
+configGroup = conf.supybot.servers.http
+
+if world.testing:
+    class TestHTTPServer(HTTPServer):
+        """A fake HTTP server for testing purpose."""
+        def __init__(self, address, handler):
+            self.server_address = address
+            self.RequestHandlerClass = handler
+            self.socket = StringIO()
+            self._notServing = Event()
+            self._notServer.set()
+
+        def fileno(self):
+            return hash(self)
+
+        def serve_forever(self, poll_interval=None):
+            self._notServing.clear()
+            self._notServing.wait()
+
+        def shutdown(self):
+            self._notServing.set()
+
+    HTTPServer = TestHTTPServer
+
+class SupyHTTPServer(HTTPServer):
+    # TODO: make this configurable
+    timeout = 0.5
+    callbacks = {}
+    running = False
+    def hook(self, subdir, callback):
+        if subdir in callbacks:
+            raise KeyError('This subdir is already hooked.')
+        else:
+            callbacks[subdir] = callback
+    def unhook(self, subdir):
+        callback = callbacks.pop(subdir) # May raise a KeyError. We don't care.
+        callback.doUnhook(self)
+        return callback
+
+class SupyHTTPRequestHandler(BaseHTTPRequestHandler):
+    def do_GET(self):
+        if self.path == '/':
+            callback = SupyIndex()
+        else:
+            subdir = self.path.split('/')[1]
+            try:
+                callback = self.server.callbacks[subdir]()
+            except KeyError:
+                callback = Supy404()
+
+        # Some shortcuts
+        for name in ('send_response', 'send_header', 'end_headers', 'rfile',
+                'wfile'):
+            setattr(callback, name, getattr(self, name))
+        # We call doGet, because this is more supybotic than do_GET.
+        callback.doGet(self, '/'.join(self.path[2:]))
+
+    def log_message(self, format, *args):
+        log.info('HTTP request: %s - %s' %
+                (self.address_string(), format % args))
+
+
+class SupyHTTPServerCallback:
+    name = "Unnamed plugin"
+    defaultResponse = """
+    This is a default response of the Supybot HTTP server. If you see this
+    message, it probably means you are developping a plugin, and you have
+    neither overriden this message or defined an handler for this query."""
+
+    def doGet(self, handler, path):
+        handler.send_response(400)
+        self.send_header('Content_type', 'text/plain')
+        self.send_header('Content-Length', len(self.defaultResponse))
+        self.end_headers()
+        self.wfile.write(self.defaultResponse)
+
+    def doUnhook(self, handler):
+        """Method called when unhooking this callback."""
+        pass
+
+class Supy404(SupyHTTPServerCallback):
+    name = "Error 404"
+    response = """
+    I am a pretty clever IRC bot, but I suck at serving Web pages, particulary
+    if I don't know what to serve.
+    What I'm saying is you just triggered a 404 Not Found, and I am not
+    trained to help you in such a case."""
+    def doGet(self, handler, path):
+        handler.send_response(404)
+        self.send_header('Content_type', 'text/plain')
+        self.send_header('Content-Length', len(self.response))
+        self.end_headers()
+        self.wfile.write(self.response)
+
+class SupyIndex(SupyHTTPServerCallback):
+    name = "index"
+    defaultResponse = "Request not handled."""
+    template = """
+    <html>
+     <head>
+      <title>Supybot Web server index</title>
+     </head>
+     <body>
+      Here is a list of the plugins that have a Web interface:
+      %s
+     </body>
+    </html>"""
+    def doGet(self, handler, path):
+        plugins = [x for x in handler.server.callbacks.items()]
+        if plugins == []:
+            response = 'No plugins available.'
+        else:
+            response = '<ul><li>%s</li></ul>' % '</li><li>'.join(
+                    ['<a href="/%s">%s</a>' % x in plugins])
+        handler.send_response(200)
+        self.send_header('Content_type', 'text/html')
+        self.send_header('Content-Length', len(response))
+        self.end_headers()
+        self.wfile.write(response)
+
+httpServer = None
+
+def startServer():
+    """Starts the HTTP server. Shouldn't be called from other modules.
+    The callback should be an instance of a child of SupyHTTPServerCallback."""
+    global httpServer
+    log.info('Starting HTTP server.')
+    address = (configGroup.host(), configGroup.port())
+    httpServer = SupyHTTPServer(address, SupyHTTPRequestHandler)
+    Thread(target=httpServer.serve_forever, name='HTTP Server').start()
+
+def stopServer():
+    """Stops the HTTP server. Should be run only from this module or from
+    when the bot is dying (ie. from supybot.world)"""
+    global httpServer
+    log.info('Stopping HTTP server.')
+    httpServer.shutdown()
+    httpServer = None
+
+if configGroup.keepAlive():
+    startServer()
+
+def hook(subdir, callback):
+    """Sets a callback for a given subdir."""
+    if httpServer is None:
+        startServer()
+    httpServer.hook(subdir, callback)
+
+def unhook(subdir):
+    """Unsets the callback assigned to the given subdir, and return it."""
+    global httpServer
+    assert httpServer is not None
+    callback = httpServer.unhook(subdir)
+    if len(httpServer.callbacks) <= 0 and not configGroup.keepAlive():
+        stopServer()