使用Python Requests与Flask传输exe文件时出现文件损坏问题

你的代码存在两处核心问题，导致exe文件传输后损坏：

问题1：发送端文件上传格式错误 #

你直接将f.read()的二进制内容作为files字典的值，不符合requests文件上传的规范。files参数需要接收文件对象，或包含文件名、内容、MIME类型的元组，这样requests才能正确生成multipart/form-data格式的请求，保证二进制数据完整传输。

问题2：服务器端接收逻辑错误 #

你用request.form["file"]获取文件内容是完全错误的：request.form仅用于处理表单文本数据，而文件上传必须用request.files。另外，对二进制内容执行encode("utf-8")会把非UTF-8兼容的字节（exe文件大量存在）强制转码，直接破坏文件结构。

修正后的发送端代码 #

import requests, shutil
targeturl = "http://127.0.0.1:5000/latest"

with open("client_copy.exe", "rb") as f:
    # 正确传递文件对象，requests会自动处理上传格式
    files = {"file": f}
    response = requests.post(targeturl, files=files)
    shutil.copyfile("client_copy.exe", "client.exe")
print(f"Request Sent. Response code: {response.status_code}. {response.reason}")

修正后的Flask服务器代码 #

from flask import request, send_file
import os

@app.route("/latest", methods=["GET", "POST"])
def latest():
    if request.method == "GET":
        path = os.path.join(os.getcwd(), "client.exe")
        return send_file(path, as_attachment=True)
    elif request.method == "POST":
        uploaded_file = request.files.get("file")
        if not uploaded_file:
            return "No file uploaded", 400
        
        # 直接读取二进制内容写入文件，跳过错误的编码步骤
        with open("client.exe", "wb") as file:
            file.write(uploaded_file.read())
        return "Success", 200
    else:
        return f"Error: {request.method} is not a valid method. Use GET or POST.", 405

内容的提问来源于stack exchange，提问作者cycooYT