view mercurial/hgweb/wsgicgi.py @ 34390:f6492f482c60

hgweb: query string arguments to control whitespace for annotate

This feature should hopefully be pretty straightforward. We simply
examine some query string arguments to feed into the diff options.

The function to obtain the diff options has been factored into its
own generic function to facilitate an upcoming change to the HTML
interface and to enable diff settings to be controlled via the same
query string arguments on other web commands.

The test output for "ignoreblanklines" didn't change. I'm not sure
why. Our test coverage for --ignore-blank-lines isn't great and I
can't figure out how to make this diff setting do anything meaningful.
On a very brief examination of the code, it is possible the setting
doesn't work because it is operating at the line level and blank lines
detection needs to examine multiple lines. But I'm not an expert in
this code, so I'm not sure.

Differential Revision: https://phab.mercurial-scm.org/D849

# hgweb/wsgicgi.py - CGI->WSGI translator
#
# Copyright 2006 Eric Hopper <[e-mail]>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
#
# This was originally copied from the public domain code at
# http://www.python.org/dev/peps/pep-0333/#the-server-gateway-side

from __future__ import absolute_import

from .. import (
    encoding,
    util,
)

from . import (
    common,
)

def launch(application):
    util.setbinary(util.stdin)
    util.setbinary(util.stdout)

    environ = dict(encoding.environ.iteritems())
    environ.setdefault('PATH_INFO', '')
    if environ.get('SERVER_SOFTWARE', '').startswith('Microsoft-IIS'):
        # IIS includes script_name in PATH_INFO
        scriptname = environ['SCRIPT_NAME']
        if environ['PATH_INFO'].startswith(scriptname):
            environ['PATH_INFO'] = environ['PATH_INFO'][len(scriptname):]

    stdin = util.stdin
    if environ.get('HTTP_EXPECT', '').lower() == '100-continue':
        stdin = common.continuereader(stdin, util.stdout.write)

    environ['wsgi.input'] = stdin
    environ['wsgi.errors'] = util.stderr
    environ['wsgi.version'] = (1, 0)
    environ['wsgi.multithread'] = False
    environ['wsgi.multiprocess'] = True
    environ['wsgi.run_once'] = True

    if environ.get('HTTPS', 'off').lower() in ('on', '1', 'yes'):
        environ['wsgi.url_scheme'] = 'https'
    else:
        environ['wsgi.url_scheme'] = 'http'

    headers_set = []
    headers_sent = []
    out = util.stdout

    def write(data):
        if not headers_set:
            raise AssertionError("write() before start_response()")

        elif not headers_sent:
            # Before the first output, send the stored headers
            status, response_headers = headers_sent[:] = headers_set
            out.write('Status: %s\r\n' % status)
            for header in response_headers:
                out.write('%s: %s\r\n' % header)
            out.write('\r\n')

        out.write(data)
        out.flush()

    def start_response(status, response_headers, exc_info=None):
        if exc_info:
            try:
                if headers_sent:
                    # Re-raise original exception if headers sent
                    raise exc_info[0](exc_info[1], exc_info[2])
            finally:
                exc_info = None     # avoid dangling circular ref
        elif headers_set:
            raise AssertionError("Headers already set!")

        headers_set[:] = [status, response_headers]
        return write

    content = application(environ, start_response)
    try:
        for chunk in content:
            write(chunk)
        if not headers_sent:
            write('')   # send headers now if body was empty
    finally:
        getattr(content, 'close', lambda : None)()