pythonでhttpのファイルアップロード

とりあえず、何も書かずにどんどん過ぎたってしまうので、Pythonでファイルをアップロードするコード。日本語のファイル名もそこそこちゃんと扱ってくれるはず。

#! /usr/bin/env python

import mimetypes
import os.path
import random
import sys
import urllib
import urllib2

OS_FILESYSTEM_ENCODING = sys.getfilesystemencoding()

FORMENCODE_HEADERS = {
     "Content-Type": "application/x-www-form-urlencoded; charset=UTF-8",
     "Accept-Language": "ja",
     "Accept-Charset": "utf-8"}

MULTIPART_HEADERS = {
     "Content-Type": 'multipart/form-data; boundary=',
     "Accept-Language": "ja",}


        
def is_multipart(postdata):
    for value in postdata.values():
        if isinstance(value, file):
            return True
    return False

def encode_postdata(postdata):
    getRandomChar = lambda: chr(random.choice(range(97, 123)))
    randomChar = [getRandomChar() for x in xrange(20)]
    boundary = "----------%s" % ("".join(randomChar))
    lines = ["--" + boundary]
    for key, value in postdata.iteritems():
        header = 'Content-Disposition: form-data; name="%s"' % key
        if hasattr(value, "name"):
            name = value.name
            if isinstance(name, str):
                name = name.decode(OS_FILESYSTEM_ENCODING)
            header += '; filename="%s"' % os.path.split(name.encode("utf-8"))[-1]
            lines.append(header)
            mtypes = mimetypes.guess_type(value.name)
            if mtypes:
                contentType = mtypes[0]
                header = "Content-Type: %s" % contentType
                lines.append(header)
            lines.append("Content-Transfer-Encoding: binary")
        else:
            lines.append(header)

        lines.append("")
        if hasattr(value, "read"):
            lines.append(value.read())
        elif isinstance(value, unicode):
            lines.append(value.encode("utf-8"))
        else:
            lines.append(value)
        lines.append("--" + boundary)
    lines[-1] += "--"

    return "\r\n".join(lines), boundary



def open_url(url, postdata=None, headers = None):
    encoded = None
    _headers = None
    if postdata:
        if is_multipart(postdata):
            encoded, boundary = encode_postdata(postdata)
            _headers = MULTIPART_HEADERS.copy()
            _headers["Content-Type"] = _headers["Content-Type"] + boundary
        else:
            encoded = urllib.urlencode(postdata)
            _headers = FORMENCODE_HEADERS

    request = urllib2.Request(url, encoded)
    if _headers:
        for key, value in _headers.iteritems():
            request.add_header(key, value)
    if headers:
        for key, value in headers.iteritems():
            request.add_header(key, value)
    opener = urllib2.build_opener()
    response = opener.open(request)

    return response


if __name__ == "__main__":
    url = "http://example.com/post"
    postdata = {"key": "value",
                "file1": open("somefile.txt", "r+b")}
    resp = open_url(url, postdata)
    print resp.read()