智能HTTP git客户端

Question

Here, this part I can't make it work.

https://gist.github.com/schacon/6092633#file-git-http-proto-txt-L313

# -*- coding: utf-8 -*-
import requests                              
url = "https://github.com/llacroix/node-nfc.git/git-upload-pack"

def make_line(line):
    prefix = "%0.4x" % (len(line) + 4)
    return "%s%s" % (prefix, line)

data = ""
data += make_line("want ba9007f12771f6fddf2b1b22888af90352588197\0 \n")
data += make_line("have 5cec4d0c777aa2bda27c6c9be8e6108ef0f08d62\n")
data += "0000"

req = requests.post(url, data, headers={'Content-Type': 'application/x-git-upload-pack-request'})
print req.text

I don't understand how I can make it work. I tried the command locally with:

git-upload-pack --stateless-rpc .

But I can't figure out to make the protocol work correctly. It either fail or return nothing locally. And Remotely, it always fails with:

IncompleteRead(0 bytes read)', ...

Answer 1

Ok, first off the solution is pretty much based on this answer for a similar question.

https://stackoverflow.com/a/31953327/54606

The documentation I linked is either wrong or really outdated. The NUL delimiter isn't "\\0" but "0000". "0000" Isn't actually ending the communication but "done" is effectively doing that.

The four char before the line are actually the length of the line including a newline and the 4 char except the 0000 is a line starts with them. Without looking at the source code, I'd expect the "0000" to behave like a reset or a flush.

The done line also have to be prefixed with the length which will be 9 chars including a newline.

The end result looks like this:

upload_pack = '%s/git-upload-pack'
url = upload_pack % (options.url)

def make_line(line):
    prefix = "%0.4x" % (len(line) + 5)
    return "%s%s\n" % (prefix, line)

def make_want(obj):
    line = make_line("want %s" % obj)
    return line + "0000"

def make_have(obj):
    return make_line("have %s" % obj)

def make_request(from_obj, to_obj):
    data = ""
    data += make_want(to_obj)
    data += make_have(from_obj)
    data += make_line("done")
    return data

headers = {
    'Content-Type': 'application/x-git-upload-pack-request',
}

req_data = make_request(options.from_obj, options.to_obj)
req = requests.post(url, req_data, headers=headers)

print req.content