Python socket 客户端 Post 参数

Question

首先让我清楚我不想使用更高级别的API，我只想使用套接字编程

我编写了以下程序来使用 POST 请求连接到服务器。

import socket
import binascii

host = "localhost"
port = 9000
message = "POST /auth HTTP/1.1\r\n"
parameters = "userName=Ganesh&password=pass\r\n"
contentLength = "Content-Length: " + str(len(parameters))
contentType = "Content-Type: application/x-www-form-urlencoded\r\n"

finalMessage = message + contentLength + contentType + "\r\n"
finalMessage = finalMessage + parameters
finalMessage = binascii.a2b_qp(finalMessage)


s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((host, port))
s.sendall(finalMessage)

print(s.recv(1024))

我在网上查看了 POST 请求是如何创建的。

不知何故，参数没有传递到服务器。我是否必须在请求之间添加或删除“\r\n”？

提前致谢，问候，象头神。

Answer 1

这一行 finalMessage = binascii.a2b_qp(finalMessage) 肯定是错误的，所以你应该完全删除该行，另一个问题是 Content-Length 之后没有换行。在这种情况下，发送到套接字的请求是(我在这里将 CR 和 LF 字符显示为 \r\n，但也会拆分线条清晰):

POST /auth HTTP/1.1\r\n
Content-Length: 31Content-Type: application/x-www-form-urlencoded\r\n
\r\n
userName=Ganesh&password=pass\r\n

很明显，这对网络服务器来说意义不大。

---

但即使在添加换行符并删除 a2b_qp 之后，问题仍然是您不是 talking HTTP/1.1那里;请求必须具有 HTTP/1.1 (RFC 2616 14.23) 的 Host header :

A client MUST include a Host header field in all HTTP/1.1 request messages . If the requested URI does not include an Internet host name for the service being requested, then the Host header field MUST be given with an empty value. An HTTP/1.1 proxy MUST ensure that any request message it forwards does contain an appropriate Host header field that identifies the service being requested by the proxy. All Internet-based HTTP/1.1 servers MUST respond with a 400 (Bad Request) status code to any HTTP/1.1 request message which lacks a Host header field.

此外，您不支持分块请求和持久连接、keepalive 或任何东西，因此您必须执行 Connection: close (RFC 2616 14.10):

HTTP/1.1 applications that do not support persistent connections MUST include the "close" connection option in every message.

因此，任何在没有 Host: header 的情况下仍能正常响应您的消息的 HTTP/1.1 服务器也已损坏。

这是您应该随该请求发送到套接字的数据:

POST /auth HTTP/1.1\r\n
Content-Type: application/x-www-form-urlencoded\r\n
Content-Length: 29\r\n
Host: localhost:9000\r\n
Connection: close\r\n
\r\n
userName=Ganesh&password=pass

请注意，您不再在正文中添加 \r\n(因此正文的长度为 29)。此外，您应该阅读响应以找出您遇到的错误。

---

在 Python 3 上，工作代码会说:

host = "localhost"
port = 9000

headers = """\
POST /auth HTTP/1.1\r
Content-Type: {content_type}\r
Content-Length: {content_length}\r
Host: {host}\r
Connection: close\r
\r\n"""

body = 'userName=Ganesh&password=pass'                                 
body_bytes = body.encode('ascii')
header_bytes = headers.format(
    content_type="application/x-www-form-urlencoded",
    content_length=len(body_bytes),
    host=str(host) + ":" + str(port)
).encode('iso-8859-1')

payload = header_bytes + body_bytes

# ...

socket.sendall(payload)