def is_git(environ):

    path_info = environ['PATH_INFO']

    isgit_path = GIT_PROTO_PAT.match(path_info)

    log.debug('pathinfo: %s detected as GIT %s' % (

        path_info, isgit_path != None)

    )

    return isgit_path

class SimpleGit(BaseVCSController):

    def _handle_request(self, environ, start_response):

        if not is_git(environ):

            return self.application(environ, start_response)

        if not self._check_ssl(environ, start_response):

            return HTTPNotAcceptable('SSL REQUIRED !')(environ, start_response)

        ipaddr = self._get_ip_addr(environ)

        username = None

        self._git_first_op = False

        # skip passing error to error controller

        environ['pylons.status_code_redirect'] = True

        #======================================================================

        # EXTRACT REPOSITORY NAME FROM ENV

        #======================================================================

        try:

            repo_name = self.__get_repository(environ)

            log.debug('Extracted repo name is %s' % repo_name)

        except:

            return HTTPInternalServerError()(environ, start_response)

        # quick check if that dir exists...

        if is_valid_repo(repo_name, self.basepath, 'git') is False:

            return HTTPNotFound()(environ, start_response)

        #======================================================================

        # GET ACTION PULL or PUSH

        #======================================================================

        action = self.__get_action(environ)

        #======================================================================

        # CHECK ANONYMOUS PERMISSION

        #======================================================================

        if action in ['pull', 'push']:

            anonymous_user = self.__get_user('default')

            username = anonymous_user.username

            anonymous_perm = self._check_permission(action, anonymous_user,

                                                    repo_name)

            if anonymous_perm is not True or anonymous_user.active is False:

                if anonymous_perm is not True:

                    log.debug('Not enough credentials to access this '

                              'repository as anonymous user')

                if anonymous_user.active is False:

                    log.debug('Anonymous access is disabled, running '

                              'authentication')

                #==============================================================

                # DEFAULT PERM FAILED OR ANONYMOUS ACCESS IS DISABLED SO WE

                # NEED TO AUTHENTICATE AND ASK FOR AUTH USER PERMISSIONS

                #==============================================================

                # Attempting to retrieve username from the container

                username = get_container_username(environ, self.config)

                # If not authenticated by the container, running basic auth

                if not username:

                    self.authenticate.realm = \

                        safe_str(self.config['rhodecode_realm'])

                    result = self.authenticate(environ)

                    if isinstance(result, str):

                        AUTH_TYPE.update(environ, 'basic')

                        REMOTE_USER.update(environ, result)

                        username = result

                    else:

                        return result.wsgi_application(environ, start_response)

                #==============================================================

                # CHECK PERMISSIONS FOR THIS REQUEST USING GIVEN USERNAME

                #==============================================================

                try:

                    user = self.__get_user(username)

                    if user is None or not user.active:

                        return HTTPForbidden()(environ, start_response)

                    username = user.username

                except:

                    log.error(traceback.format_exc())

                    return HTTPInternalServerError()(environ, start_response)

                #check permissions for this repository

                perm = self._check_permission(action, user, repo_name)

                if perm is not True:

                    return HTTPForbidden()(environ, start_response)

        # extras are injected into UI object and later available

        # in hooks executed by rhodecode

        extras = {

            'ip': ipaddr,

            'username': username,

            'action': action,

            'repository': repo_name,

            'scm': 'git',

            'make_lock': None,

            'locked_by': [None, None]

        }

        #===================================================================

        # GIT REQUEST HANDLING

        #===================================================================

        repo_path = os.path.join(safe_str(self.basepath), safe_str(repo_name))

        log.debug('Repository path is %s' % repo_path)

        # CHECK LOCKING only if it's not ANONYMOUS USER

        if username != User.DEFAULT_USER:

            log.debug('Checking locking on repository')

            (make_lock,

             locked,

             locked_by) = self._check_locking_state(

                            environ=environ, action=action,

                            repo=repo_name, user_id=user.user_id

                       )

            # store the make_lock for later evaluation in hooks

            extras.update({'make_lock': make_lock,

                           'locked_by': locked_by})

        # set the environ variables for this request

        os.environ['RC_SCM_DATA'] = json.dumps(extras)

        log.debug('HOOKS extras is %s' % extras)

        baseui = make_ui('db')

        self.__inject_extras(repo_path, baseui, extras)

        try:

            # invalidate cache on push

            if action == 'push':

                self._invalidate_cache(repo_name)

            self._handle_githooks(repo_name, action, baseui, environ)

            log.info('%s action on GIT repo "%s"' % (action, repo_name))

            app = self.__make_app(repo_name, repo_path, extras)

            return app(environ, start_response)

        except HTTPLockedRC, e:

            log.debug('Repositry LOCKED ret code 423!')

            return e(environ, start_response)

        except Exception:

            log.error(traceback.format_exc())

            return HTTPInternalServerError()(environ, start_response)

    def __make_app(self, repo_name, repo_path, extras):

        """

        Make an wsgi application using dulserver

        :param repo_name: name of the repository

        :param repo_path: full path to the repository

        """

        from rhodecode.lib.middleware.pygrack import make_wsgi_app

        app = make_wsgi_app(

            repo_root=safe_str(self.basepath),

            repo_name=repo_name,

            extras=extras,

        )

        app = GunzipFilter(LimitedInputFilter(app))

        return app

    def __get_repository(self, environ):

        """

        Get's repository name out of PATH_INFO header

        :param environ: environ where PATH_INFO is stored

        """

        try:

            environ['PATH_INFO'] = self._get_by_id(environ['PATH_INFO'])

            repo_name = GIT_PROTO_PAT.match(environ['PATH_INFO']).group(1)

        except:

            log.error(traceback.format_exc())

            raise

        return repo_name

    def __get_user(self, username):

        return User.get_by_username(username)

    def __get_action(self, environ):

        """

        Maps git request commands into a pull or push command.

        :param environ:

        """

        service = environ['QUERY_STRING'].split('=')

        if len(service) > 1:

            service_cmd = service[1]

            mapping = {

                'git-receive-pack': 'push',

                'git-upload-pack': 'pull',

            }

            op = mapping[service_cmd]

            self._git_stored_op = op

            return op