static.py

python web programming 部分

#
# $Workfile: Static.py $ $Revision: 8 $
# $Date: 9/12/01 10:54a $ $Author: Sholden $
#
import Web
from Error import Error
import os
from mimetypes import guess_type
import mx.DateTime as mxdt
import mx.DateTime.ARPA as arpa


class Page(Web.Page):
    """Handle content present as a file in the virtual web filestore.

    Note that a whole passel of stuff is inherited, from Web.Page,
    much of which is neither required nor used because the content
    is simply dragged from a file and squirted down to the client.
    """

    def Content(self):
        """Generate static content by squirting file content."""
        if self.ReturnCode() == 200:    # No error raised
            if self.op.upper() != "GET":
                raise Error(405, "Method Not Allowed", errmsg="Illegal Operation")
            else:
                if not self.path:
                    raise Error(400, "Bad Request", errmsg="Missing file path")
                fname = self.path[-1]
                ext = os.path.splitext(fname)[1]
                mimetype, encoding = guess_type(fname)
                if not mimetype:
                    raise Error(415, "Unsupported Media Type", errmsg="Content type not recognised")
                try:
                    filepath = os.sep.join(self.initpath + self.path)
                    ims = self.headers.getheader("if-modified-since")
                    s = os.stat(filepath)
                    mdt = mxdt.local2gm(mxdt.DateTimeFromTicks(s[8]))
                    if ims:             # optimize if file not modified
                        sdt = arpa.ParseDateTime(ims.split(";")[0])
                        # print "If-mod-since:", ims, "Last-mod:", mdt
                        if mdt <= sdt:
                            raise Error(304, "Not modified",
                                    errcontent="Not modified")
                    self.oheaders.append("Last-Modified: %s" % arpa.str(mxdt.DateTimeFromTicks(mdt)))
                    if encoding:
                        enchdr = "Content-Encoding: %s\n" % encoding
                    else:
                        enchdr = ""
                    f = open(filepath, "rb")
                    img = f.read()
                    return img
                except (IOError, OSError):
                    raise Error(404, "Not Found", errmsg="Content Not Found")
        else:
            return Web.Page.Content(self) # standard method has smarts we do not

def test():
    import rfc822, StringIO, Session
    h = rfc822.Message(StringIO.StringIO("""If-Modified-Since: Mon, 09 Sep 2001 09:00:00
"""))
    s = Session.Session(1)
    p = Page("GET", ["Windows.htm"], {}, s, h, Initpath=["text"])
    import sys
    sys.stdout.write(p.Generate())
    
if __name__ == "__main__":
    test()