httpserver.py

__all__ = ["runsimple"]

import sys, os
from SimpleHTTPServer import SimpleHTTPRequestHandler
import urllib
import posixpath

import webapi as web
import net
import utils

def runbasic(func, server_address=("0.0.0.0", 8080)):
    """
    Runs a simple HTTP server hosting WSGI app `func`. The directory `static/` 
    is hosted statically.

    Based on [WsgiServer][ws] from [Colin Stewart][cs].
    
  [ws]: http://www.owlfish.com/software/wsgiutils/documentation/wsgi-server-api.html
  [cs]: http://www.owlfish.com/
    """
    # Copyright (c) 2004 Colin Stewart (http://www.owlfish.com/)
    # Modified somewhat for simplicity
    # Used under the modified BSD license:
    # http://www.xfree86.org/3.3.6/COPYRIGHT2.html#5

    import SimpleHTTPServer, SocketServer, BaseHTTPServer, urlparse
    import socket, errno
    import traceback

    class WSGIHandler(SimpleHTTPServer.SimpleHTTPRequestHandler):
        def run_wsgi_app(self):
            protocol, host, path, parameters, query, fragment = \
                urlparse.urlparse('http://dummyhost%s' % self.path)

            # we only use path, query
            env = {'wsgi.version': (1, 0)
                   ,'wsgi.url_scheme': 'http'
                   ,'wsgi.input': self.rfile
                   ,'wsgi.errors': sys.stderr
                   ,'wsgi.multithread': 1
                   ,'wsgi.multiprocess': 0
                   ,'wsgi.run_once': 0
                   ,'REQUEST_METHOD': self.command
                   ,'REQUEST_URI': self.path
                   ,'PATH_INFO': path
                   ,'QUERY_STRING': query
                   ,'CONTENT_TYPE': self.headers.get('Content-Type', '')
                   ,'CONTENT_LENGTH': self.headers.get('Content-Length', '')
                   ,'REMOTE_ADDR': self.client_address[0]
                   ,'SERVER_NAME': self.server.server_address[0]
                   ,'SERVER_PORT': str(self.server.server_address[1])
                   ,'SERVER_PROTOCOL': self.request_version
                   }

            for http_header, http_value in self.headers.items():
                env ['HTTP_%s' % http_header.replace('-', '_').upper()] = \
                    http_value

            # Setup the state
            self.wsgi_sent_headers = 0
            self.wsgi_headers = []

            try:
                # We have there environment, now invoke the application
                result = self.server.app(env, self.wsgi_start_response)
                try:
                    try:
                        for data in result:
                            if data: 
                                self.wsgi_write_data(data)
                    finally:
                        if hasattr(result, 'close'): 
                            result.close()
                except socket.error, socket_err:
                    # Catch common network errors and suppress them
                    if (socket_err.args[0] in \
                       (errno.ECONNABORTED, errno.EPIPE)): 
                        return
                except socket.timeout, socket_timeout: 
                    return
            except:
                print >> web.debug, traceback.format_exc(),

            if (not self.wsgi_sent_headers):
                # We must write out something!
                self.wsgi_write_data(" ")
            return

        do_POST = run_wsgi_app
        do_PUT = run_wsgi_app
        do_DELETE = run_wsgi_app

        def do_GET(self):
            if self.path.startswith('/static/'):
                SimpleHTTPServer.SimpleHTTPRequestHandler.do_GET(self)
            else:
                self.run_wsgi_app()

        def wsgi_start_response(self, response_status, response_headers, 
                              exc_info=None):
            if (self.wsgi_sent_headers):
                raise Exception \
                      ("Headers already sent and start_response called again!")
            # Should really take a copy to avoid changes in the application....
            self.wsgi_headers = (response_status, response_headers)
            return self.wsgi_write_data

        def wsgi_write_data(self, data):
            if (not self.wsgi_sent_headers):
                status, headers = self.wsgi_headers
                # Need to send header prior to data
                status_code = status[:status.find(' ')]
                status_msg = status[status.find(' ') + 1:]
                self.send_response(int(status_code), status_msg)
                for header, value in headers:
                    self.send_header(header, value)
                self.end_headers()
                self.wsgi_sent_headers = 1
            # Send the data
            self.wfile.write(data)

    class WSGIServer(SocketServer.ThreadingMixIn, BaseHTTPServer.HTTPServer):
        def __init__(self, func, server_address):
            BaseHTTPServer.HTTPServer.__init__(self, 
                                               server_address, 
                                               WSGIHandler)
            self.app = func
            self.serverShuttingDown = 0

    print "http://%s:%d/" % server_address
    WSGIServer(func, server_address).serve_forever()

# The WSGIServer instance. 
# Made global so that it can be stopped in embedded mode.
server = None

def runsimple(func, server_address=("0.0.0.0", 8080)):
    """
    Runs [CherryPy][cp] WSGI server hosting WSGI app `func`. 
    The directory `static/` is hosted statically.

    [cp]: http://www.cherrypy.org
    """
    global server
    func = StaticMiddleware(func)
    func = LogMiddleware(func)
    
    server = WSGIServer(server_address, func)

    if server.ssl_adapter:
        print "https://%s:%d/" % server_address
    else:
        print "http://%s:%d/" % server_address

    try:
        server.start()
    except (KeyboardInterrupt, SystemExit):
        server.stop()
        server = None

def WSGIServer(server_address, wsgi_app):
    """Creates CherryPy WSGI server listening at `server_address` to serve `wsgi_app`.
    This function can be overwritten to customize the webserver or use a different webserver.
    """
    import wsgiserver
    
    # Default values of wsgiserver.ssl_adapters uses cherrypy.wsgiserver
    # prefix. Overwriting it make it work with web.wsgiserver.
    wsgiserver.ssl_adapters = {
        'builtin': 'web.wsgiserver.ssl_builtin.BuiltinSSLAdapter',
        'pyopenssl': 'web.wsgiserver.ssl_pyopenssl.pyOpenSSLAdapter',
    }
    
    server = wsgiserver.CherryPyWSGIServer(server_address, wsgi_app, server_name="localhost")
        
    def create_ssl_adapter(cert, key):
        # wsgiserver tries to import submodules as cherrypy.wsgiserver.foo.
        # That doesn't work as not it is web.wsgiserver. 
        # Patching sys.modules temporarily to make it work.
        import types
        cherrypy = types.ModuleType('cherrypy')
        cherrypy.wsgiserver = wsgiserver
        sys.modules['cherrypy'] = cherrypy
        sys.modules['cherrypy.wsgiserver'] = wsgiserver
        
        from wsgiserver.ssl_pyopenssl import pyOpenSSLAdapter
        adapter = pyOpenSSLAdapter(cert, key)
        
        # We are done with our work. Cleanup the patches.
        del sys.modules['cherrypy']
        del sys.modules['cherrypy.wsgiserver']

        return adapter

    # SSL backward compatibility
    if (server.ssl_adapter is None and
        getattr(server, 'ssl_certificate', None) and
        getattr(server, 'ssl_private_key', None)):
        server.ssl_adapter = create_ssl_adapter(server.ssl_certificate, server.ssl_private_key)

    server.nodelay = not sys.platform.startswith('java') # TCP_NODELAY isn't supported on the JVM
    return server

class StaticApp(SimpleHTTPRequestHandler):
    """WSGI application for serving static files."""
    def __init__(self, environ, start_response):
        self.headers = []
        self.environ = environ
        self.start_response = start_response

    def send_response(self, status, msg=""):
        self.status = str(status) + " " + msg

    def send_header(self, name, value):
        self.headers.append((name, value))

    def end_headers(self):
        pass

    def log_message(*a): pass

    def __iter__(self):
        environ = self.environ

        self.path = environ.get('PATH_INFO', '')
        self.client_address = environ.get('REMOTE_ADDR','-'), \
                              environ.get('REMOTE_PORT','-')
        self.command = environ.get('REQUEST_METHOD', '-')

        from cStringIO import StringIO
        self.wfile = StringIO() # for capturing error

        try:
            path = self.translate_path(self.path)
            etag = '"%s"' % os.path.getmtime(path)
            client_etag = environ.get('HTTP_IF_NONE_MATCH')
            self.send_header('ETag', etag)
            if etag == client_etag:
                self.send_response(304, "Not Modified")
                self.start_response(self.status, self.headers)
                raise StopIteration
        except OSError:
            pass # Probably a 404

        f = self.send_head()
        self.start_response(self.status, self.headers)

        if f:
            block_size = 16 * 1024
            while True:
                buf = f.read(block_size)
                if not buf:
                    break
                yield buf
            f.close()
        else:
            value = self.wfile.getvalue()
            yield value

class StaticMiddleware:
    """WSGI middleware for serving static files."""
    def __init__(self, app, prefix='/static/'):
        self.app = app
        self.prefix = prefix
        
    def __call__(self, environ, start_response):
        path = environ.get('PATH_INFO', '')
        path = self.normpath(path)

        if path.startswith(self.prefix):
            return StaticApp(environ, start_response)
        else:
            return self.app(environ, start_response)

    def normpath(self, path):
        path2 = posixpath.normpath(urllib.unquote(path))
        if path.endswith("/"):
            path2 += "/"
        return path2

    
class LogMiddleware:
    """WSGI middleware for logging the status."""
    def __init__(self, app):
        self.app = app
        self.format = '%s - - [%s] "%s %s %s" - %s'
    
        from BaseHTTPServer import BaseHTTPRequestHandler
        import StringIO
        f = StringIO.StringIO()
        
        class FakeSocket:
            def makefile(self, *a):
                return f
        
        # take log_date_time_string method from BaseHTTPRequestHandler
        self.log_date_time_string = BaseHTTPRequestHandler(FakeSocket(), None, None).log_date_time_string
        
    def __call__(self, environ, start_response):
        def xstart_response(status, response_headers, *args):
            out = start_response(status, response_headers, *args)
            self.log(status, environ)
            return out

        return self.app(environ, xstart_response)
             
    def log(self, status, environ):
        outfile = environ.get('wsgi.errors', web.debug)
        req = environ.get('PATH_INFO', '_')
        protocol = environ.get('ACTUAL_SERVER_PROTOCOL', '-')
        method = environ.get('REQUEST_METHOD', '-')
        host = "%s:%s" % (environ.get('REMOTE_ADDR','-'), 
                          environ.get('REMOTE_PORT','-'))

        time = self.log_date_time_string()

        msg = self.format % (host, time, protocol, method, req, status)
        print >> outfile, utils.safestr(msg)