Pull request merge script

bin/ckan-merge-pr.py

@@ -0,0 +1,86 @@
+#!/usr/bin/python3
+
+# https://github.com/KSP-CKAN/CKAN/wiki/Releasing-a-new-CKAN-client#when-merging-pull-requests
+
+import sys
+from pathlib import Path
+from subprocess import run
+from exitstatus import ExitStatus
+import click
+from click import command, option, argument
+from git import Repo
+from github import Github
+
+@command()
+@option('--repo-path', type=click.Path(exists=True, file_okay=False),
+        default='.', help='Path to CKAN working copy')
+@option('--token', required=False, envvar='GITHUB_TOKEN')
+@argument('pr_num', type=click.INT)
+def merge_pr(repo_path: str, token: str, pr_num: int) -> None:
+    r = Repo(repo_path)
+    pr = Github(token).get_repo('KSP-CKAN/CKAN').get_pull(pr_num)
+    # Make sure master is checked out
+    if r.head.ref.name != 'master':
+        print('Not on master branch!')
+        # Bail and let user get his or her repo in order
+        sys.exit(ExitStatus.failure)
+    # Make sure master is up to date
+    master_remote = r.remotes[r.head.ref.tracking_branch().remote_name]
+    print(f'Fetching {master_remote.name}...')
+    master_remote.fetch()
+    remote_master = r.head.ref.tracking_branch()
+    if r.head.commit.hexsha != remote_master.commit.hexsha:
+        print(f'master branch is not up to date!')
+        sys.exit(ExitStatus.failure)
+    # Make sure PR's branch exists
+    local_branch = pr.head.ref
+    branch = r.heads[local_branch]
+    # Fetch remote to make sure we aren't missing changes
+    tracking = branch.tracking_branch()
+    if not tracking:
+        print(f'Upstream {pr.head.label} missing!')
+        sys.exit(ExitStatus.failure)
+    remote = r.remotes[tracking.remote_name]
+    if remote.name != master_remote.name:
+        print(f'Fetching {remote.name}...')
+        remote.fetch()
+    # Make sure branch is identical to its upstream
+    if branch.commit.hexsha != pr.head.sha:
+        print(f'Branch {local_branch} not up to date!')
+        # Bail and let the user figure it out, no way we can safely cover all possibilities here
+        sys.exit(ExitStatus.failure)
+    # Get reviewers from PR
+    reviewers = [rvw.user.login for rvw in pr.get_reviews() if rvw.state == 'APPROVED']
+    if not reviewers:
+        print(f'PR #{pr_num} is not approved!')
+        sys.exit(ExitStatus.failure)
+    # Get title from PR
+    pr_title = pr.title
+    # Get author from PR
+    author = pr.user.login
+    # Merge the branch with no-commit and no-ff
+    base = r.merge_base(branch, r.head)
+    r.index.merge_tree(branch, base=base)
+    # Update the working copy
+    r.index.checkout(force=True)
+    # Print line to add to CHANGELOG.md at top of file, user needs to move it to the right spot
+    changelog_path = Path(repo_path) / 'CHANGELOG.md'
+    with open(changelog_path, 'r+') as changelog:
+        lines = [f'- [UNKNOWN] {pr_title} (#{pr_num} by: {author}; reviewed: {", ".join(reviewers)})\n',
+                 *changelog.readlines()]
+        changelog.seek(0)
+        changelog.writelines(lines)
+    # Edit CHANGELOG.md
+    editor=r.config_reader().get('core', 'editor')
+    run([editor, changelog_path])
+    # Stage change log
+    r.index.add([changelog_path.as_posix()])
+    # Commit
+    r.index.commit(f'Merge #{pr_num} {pr_title}',
+                   parent_commits=(r.head.commit, branch.commit))
+
+    # Don't push, let the user inspect and decide
+    sys.exit(ExitStatus.success)
+
+if __name__ == '__main__':
+    merge_pr()