mapsite.py

python web programming 部分

"""Used to instantiate required page generators, and look up realm authentication data."""

import urllib
import SiteSpec, Static, ErrorPages
from types import ClassType, DictType, StringType

def PageSpec(op, path, query, session, headers,
    Map=SiteSpec.PageMap, Realm=None, PathFound=None):
    """Return the page processor and authentication realm corresponding to a path."""
    if not path:
        return ErrorPages.Error404Page(op, PathFound, query, session, headers, Realm=None)
    pathel = path[0]
    if not PathFound:
        PathFound = [pathel]
    else:
        PathFound.append(pathel)
    del path[0]
    try:
        item, realm = Map[pathel]
        if not realm:
            realm = Realm # Inherit realm from containing tree
        itemtype = type(item)
        if itemtype == DictType:
            return PageSpec(op, path, query, session, headers,
                             Map=item, Realm=realm, PathFound=PathFound)
        elif len(PathFound) and not len(path): # A mapped element was not followed by a "/"
            URI = "/".join([""]+PathFound+path+[""])
            if query:
                URI += "?" + urllib.urlencode(query)
            return ErrorPages.Error301Page(op, path, query, session, headers, Realm=realm,
                             oHeaders=["Location: %s" % URI])
        if itemtype == StringType:
            return Static.Page(op, path, query, session, headers,
                            Realm=realm, Initpath=item.split("/"))
        elif itemtype == ClassType:
            if path[-1] == "": # remove evidence of trailing slash
                del path[-1]
            return item(op, path, query, session, headers,
                         Realm=realm, Initpath=PathFound)
        else:
            raise KeyError
    except KeyError:
        return ErrorPages.Error404Page(op, path, query, session, headers, Realm=None)

def RealmData(realm):
    try:
        return SiteSpec.RealmAuth[realm]
    except KeyError:
        return None