annotate mercurial/hgweb/request.py @ 2506:d0db3462d568

This patch make several WSGI related alterations.

First, it changes the server to be almost a generic WSGI server.

Second, it changes request.py to have wsgiapplication and
_wsgirequest.  wsgiapplication is a class that creates _wsgirequests
when called by a WSGI compliant server.  It needs to know whether
or not it should create hgwebdir or hgweb requests.

Lastly, wsgicgi.py is added, and the CGI scripts are altered to
use it to launch wsgiapplications in a WSGI compliant way.

As a side effect, all the keepalive code has been removed from
request.py.  This code needs to be moved so that it is exclusively
in server.py

# hgweb/request.py - An http request from either CGI or the standalone server.
#
# Copyright 21 May 2005 - (c) 2005 Jake Edge <[e-mail]>
# Copyright 2005 Matt Mackall <[e-mail]>
#
# This software may be used and distributed according to the terms
# of the GNU General Public License, incorporated herein by reference.

from mercurial.demandload import demandload
demandload(globals(), "socket sys cgi os errno")
from mercurial.i18n import gettext as _

class wsgiapplication(object):
    def __init__(self, destmaker):
        self.destmaker = destmaker

    def __call__(self, wsgienv, start_response):
        return _wsgirequest(self.destmaker(), wsgienv, start_response)

class _wsgioutputfile(object):
    def __init__(self, request):
        self.request = request

    def write(self, data):
        self.request.write(data)
    def writelines(self, lines):
        for line in lines:
            self.write(line)
    def flush(self):
        return None
    def close(self):
        return None

class _wsgirequest(object):
    def __init__(self, destination, wsgienv, start_response):
        version = wsgienv['wsgi.version']
        if (version < (1,0)) or (version >= (2, 0)):
            raise RuntimeError("Unknown and unsupported WSGI version %d.%d" \
                               % version)
        self.inp = wsgienv['wsgi.input']
        self.out = _wsgioutputfile(self)
        self.server_write = None
        self.err = wsgienv['wsgi.errors']
        self.threaded = wsgienv['wsgi.multithread']
        self.multiprocess = wsgienv['wsgi.multiprocess']
        self.run_once = wsgienv['wsgi.run_once']
        self.env = wsgienv
        self.form = cgi.parse(self.inp, self.env, keep_blank_values=1)
        self.start_response = start_response
        self.headers = []
        destination.run(self)

    def __iter__(self):
        return iter([])

    def read(self, count=-1):
        return self.inp.read(count)

    def write(self, *things):
        if self.server_write is None:
            if not self.headers:
                raise RuntimeError("request.write called before headers sent.")
            self.server_write = self.start_response('200 Script output follows',
                                                    self.headers)
            self.start_response = None
            self.headers = None
        for thing in things:
            if hasattr(thing, "__iter__"):
                for part in thing:
                    self.write(part)
            else:
                try:
                    self.server_write(str(thing))
                except socket.error, inst:
                    if inst[0] != errno.ECONNRESET:
                        raise

    def header(self, headers=[('Content-type','text/html')]):
        self.headers.extend(headers)

    def httphdr(self, type, filename=None, length=0, headers={}):
        headers = headers.items()
        headers.append(('Content-type', type))
        if filename:
            headers.append(('Content-disposition', 'attachment; filename=%s' %
                            filename))
        if length:
            headers.append(('Content-length', str(length)))
        self.header(headers)