multipart/form-data的请求头必须包含一个特殊的头信息：Content-Type，且其值也必须规定为multipart/form-data，同时还需要规定一个内容分割符用于分割请求体中的多个post的内容，如文件内容和文本内容自然需要分割开来，不然接收方就无法正常解析和还原这个文件了。
import os, random, sys, requestsfrom requests_toolbelt.multipart.encoder import MultipartEncoderurl = 'http://127.0.0.1/sendmsg'argvstr = sys.argv[1:]argv_dict = {}for argv in argvstr : argv = str(argv).replace("/r/n" , "") DICT = eval(argv) argv_dict.update(DICT)headers = { 'User-Agent': 'Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:50.0) Gecko/20100101 Firefox/50.0', 'Referer': url }multipart_encoder = MultipartEncoder( fields={ 'username': argv_dict['username'], 'pwd': argv_dict['pwd'], 'type': 'txt', 'friendfield': argv_dict['friendfield'], 'friend': argv_dict['friend'], 'content': argv_dict['content'], 'file': (os.path.basename(argv_dict['file']) , open(argv_dict['file'], 'rb'), 'application/octet-stream') #file为路径 }, boundary='-----------------------------' + str(random.randint(1e28, 1e29 - 1)) )headers['Content-Type'] = multipart_encoder.content_type#请求头必须包含一个特殊的头信息，类似于Content-Type: multipart/form-data; boundary=${bound}r = requests.post(url, data=multipart_encoder, headers=headers)print(r.text)#注意，不要设置cookies等其他参数，否则会报错# 例子/usr/local/python36/bin/python3 /opt/lykchat/test_upload.py "{'username':'lykchat','pwd':'123456','type':'img','friendfield':'1','friend':'xxxx','content':'恭喜发财','file':'/root/b.jpg'}"#等同于curl -F "file=@/root/a" 'http://127.0.0.1/sendmsg?username=lykchat&pwd=123456&type=img&friendfield=1&friend=xxxx&content=恭喜发财' 
