upload_server.py：

#!/usr/bin/env python
# coding=utf-8
# 文件上传服务器端,只考虑文件在当前目录下

import flask

app = flask.Flask(__name__)

@app.route("/upload",methods=["POST"])
def uploadFile():
    # msg = ""
    try:       
        if "fileName" in flask.request.values:
            fileName = flask.request.values.get("fileName")
            data = flask.request.get_data()
            # 获取上传的文件名字：图像.jpg
            # file = fileName[fileName.rfind("\\")+1:]
            # 获取上传文件的路径D:\PycharmDevelop
            # path = fileName[:fileName.rfind("\\")]
            # with open(path +"\\"+"upload"+file,"wb")as f:
            #     f.write(data)
            with open("upload"+fileName,"wb")as f:
                f.write(data)
            msg = "OK"
        else:
            msg = "没有按要求上传文件"
    except Exception as e:
        print(e)
        msg = str(e)
    return msg


if __name__ == "__main__":
    app.run()

upload _client.py：

#!/usr/bin/env python
# coding=utf-8
# 文件上传客户端

import urllib.request
import urllib.parse
import os,time

url = "http://127.0.0.1:5000/upload"
fileName = input("请输入要上传的文件名字：")
try:
    if os.path.exists(fileName):
        with open(fileName,"rb")as f:
            data = f.read()
        print("准备上传文件："+fileName)
        time.sleep(3)
        headers = {'content-type':'application/octet-stream'}
        purl = url + "?fileName="+urllib.parse.quote(fileName)
        req = urllib.request.Request(purl,data,headers)
        response = urllib.request.urlopen(req)
        msg = response.read().decode()
        print(msg)
        if msg == "OK":
            print("成功上传文件：%s，大小为%s字节。"%(fileName,len(data)))
        else:
            print(msg)
    else:
        print("文件不存在！")

except Exception as e:
    print(e)