Python socket client Post parameters

http, post, python, sockets

Solution

This line `finalMessage = binascii.a2b_qp(finalMessage)` is certainly wrong, so you should remove the line completely, another problem is that there is no new-line missing after `Content-Length`. In this case the request sent to the socket is (I am showing the `CR` and `LF` characters here as `\r\n`, but also splitting lines for clarity):

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

So obviously this does not make much sense to the web server.

But even after adding a newline and removing `a2b_qp`, there is still the problem is that you are not talking `HTTP/1.1` there; the request must have a `Host` header for HTTP/1.1 (RFC 2616 14.23):

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.

Also you do not support chunked requests and persistent connections, keepalives or anything, so you must do `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.

Thus, any `HTTP/1.1` server that would still respond normally to your messages without `Host:` header is also broken.

This the data that you should send to the socket with that request:

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

Note that you'd not add the `\r\n` in the body anymore (thus the length of body 29). Also you should read the response to find out whatever the error is that you're getting.

On Python 3 the working code would say:

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)

Problem

Original source