git-update-pr

#!/usr/bin/env python

import re
import os
import sys

from time import sleep

from subprocess import check_output
from subprocess import call
from subprocess import Popen
from subprocess import PIPE

from getpass import getpass

from tempfile import NamedTemporaryFile

from git import Repo
from github import Github

from github.GithubException import UnknownObjectException

import github
#github.enable_console_debug_logging()

# Approximate value of the magic length that GitHub will allow
#   for the length of a new comment:
PATCH_MAX_LENGTH = 6144

PR_REGEX = re.compile("``` diff.*```", re.DOTALL)
GITHUB_TOKEN = os.path.expanduser("~/.git_pull_req_auth")

github = None

if not os.path.exists(GITHUB_TOKEN):
    print 'Script requires GitHub login/password (only once)...'
    user = raw_input("GitHub username: ")
    pw = getpass("GitHub password: ")
    github = Github(user, pw)
    user = github.get_user()
    print 'Creating authorization token...'
    auth = user.create_authorization(
            scopes=["repo"],
            note="git-update-pr",
            note_url="https://github.com/cozybit/cozyreview")
    open(GITHUB_TOKEN, 'w').write(auth.token)
    token = auth.token
else:
    token = open(GITHUB_TOKEN, 'r').read()

github = Github(token)
user = github.get_user()
print 'Token resolved to GitHub username:', user.login

try:
    print 'Getting repo for current directory...'
    gitrepo = Repo(os.getcwd())
except:
    sys.stderr.write('ERROR: Failed to find git repository\n')
    sys.exit(1)

try:
    print 'Finding URL of remote named \'origin\' (which must use the SSH protocol)...'
    remote_url = gitrepo.config_reader().get('remote "origin"', "url")
except:
    sys.stderr.write("ERROR: Failed to find remote named 'origin'\n")
    sys.exit(1)

if not remote_url.startswith("git@github.com"):
    sys.stderr.write("ERROR: Expected remote to start with 'git@github.com'\n")
    sys.exit(1)

if not remote_url.endswith(".git"):
    sys.stderr.write("ERROR: Expected remote to end with '.git'\n")
    sys.exit(1)

if ':' not in remote_url:
    sys.stderr.write("ERROR: Expected remote contain ':'\n")
    sys.exit(1)

_, orgprojgit = remote_url.split(":")
orgname, projgit = orgprojgit.split('/')
projname = projgit[:-4]

try:
    org = github.get_organization(orgname)
except UnknownObjectException:
    org = github.get_user(orgname)

print 'Getting repo name for:', projname

ghrepo = org.get_repo(projname)
print 'Repository found:', ghrepo.html_url

print 'Updating remote \'origin\' to find new commits...'
os.spawnvp(os.P_WAIT, "git", ["git", "remote", "update", "origin"])

active_branch_name = gitrepo.active_branch.name
print 'Using branch name for pull request:', active_branch_name

cmd = ["git", "cherry", "origin/" + active_branch_name, active_branch_name]

has_new_commits = 0 < len(check_output(cmd).splitlines())

if not ('UPR_FORCE' in os.environ and os.environ['UPR_FORCE'] == '1'):
    if not has_new_commits:
        sys.stderr.write("ERROR: No new commits found, aborting\n")
        sys.exit(1)

print 'Finding pull request for branch name:', active_branch_name

for pr in ghrepo.get_pulls():

    org_name, branch_name = pr.head.label.split(":")
    if branch_name != active_branch_name:
        continue

    updated_patch = check_output(
        ["git", "format-patch", "--stdout", "origin/master"])
        #["git", "format-patch", "--stdout", "origin/" + active_branch_name])

    if len(updated_patch) > PATCH_MAX_LENGTH:
        sys.stderr.write("***************************************\n")
        sys.stderr.write("* WARNING: Patch too big, truncating! *\n")
        sys.stderr.write("***************************************\n")

    new_pr_diff = "``` diff\n" + updated_patch[:PATCH_MAX_LENGTH] + "\n```"
    updated_pr_body = PR_REGEX.sub(new_pr_diff, pr.body)
    updated_pr_body = updated_pr_body.replace("\r\n", "\n")

    editor = "vi"
    if 'EDITOR' in os.environ:
        editor = os.environ['EDITOR']

    fp, fp_orig = NamedTemporaryFile(), NamedTemporaryFile()

    title = pr.title + "\n\n"
    fp.write(title)
    fp.write(updated_pr_body)

    fp.flush()
    fp.seek(0)
    fp_orig.write(fp.read())

    fp_orig.flush()

    exit_code = os.spawnvp(os.P_WAIT, editor, [editor, fp.name])
    if exit_code != 0:
        sys.stderr.write("ERROR: Editor was aborted\n")
        sys.exit(1)

    exit_code = Popen(["diff", "-w", fp_orig.name, fp.name],
            stdout=PIPE, stderr=PIPE).wait()

    if exit_code == 0:
        sys.stderr.write("ERROR: Pull request body not modified\n")
        sys.exit(1)

    fp.seek(0)

    lines = fp.read().splitlines()
    updated_title, updated_pr_body = lines[0], str.join("\n", lines[1:]).strip()

    print 'Updating pull request, adding new issue comment with new diff (len=%d)...' % (len(updated_title+updated_pr_body),)

    pr.edit(title=updated_title, body=updated_pr_body)
    sleep(1)

    pr.create_issue_comment(updated_pr_body)

    #pr.create_issue_comment(new_pr_diff)


print
print '*** NOTE ********************************************'
print
print 'Please run:'
print '\tgit push -f origin ', active_branch_name
print
print '... to finish updating pull-request'
print
print '*****************************************************'
print