From 30eee512351ca9369cdea7ccfee747264336dc62 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?L=C3=A1szl=C3=B3=20Vask=C3=B3?= <laszlo.vasko@outlook.com>
Date: Fri, 1 Jan 2021 01:18:07 +0000
Subject: [PATCH] github actions: action to update init.el

---
 .github/workflows/update-dependencies.yml |   6 ++
 .github/workflows/update_init_el.py       | 109 ++++++++++++++++++++++
 2 files changed, 115 insertions(+)
 create mode 100755 .github/workflows/update_init_el.py

diff --git a/.github/workflows/update-dependencies.yml b/.github/workflows/update-dependencies.yml
index 9cad175..19d504b 100644
--- a/.github/workflows/update-dependencies.yml
+++ b/.github/workflows/update-dependencies.yml
@@ -23,3 +23,9 @@ jobs:
         GITHUB_BASE_BRANCH: develop
       run: |
         nix develop -c .github/workflows/update_flake_lock.py
+    - name: Create PR for updated init.el
+      env:
+        GITHUB_API_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        GITHUB_BASE_BRANCH: develop
+      run: |
+        nix develop -c .github/workflows/update_init_el.py
diff --git a/.github/workflows/update_init_el.py b/.github/workflows/update_init_el.py
new file mode 100755
index 0000000..6f6210e
--- /dev/null
+++ b/.github/workflows/update_init_el.py
@@ -0,0 +1,109 @@
+#!/usr/bin/env python3
+import sys
+from difflib import unified_diff
+
+from os import environ as env
+from typing import cast
+from github import Github
+from github.ContentFile import ContentFile
+from github.GithubException import GithubException
+from github.Repository import Repository
+
+API_TOKEN = env["GITHUB_API_TOKEN"]
+REPOSITORY = env["GITHUB_REPOSITORY"]
+BASE_BRANCH = env.get("GITHUB_BASE_BRANCH", "master")
+DRY_RUN = bool(env.get("GITHUB_DRY_RUN", False))
+
+INIT_EL = "test/doom.d/init.el"
+UPSTREAM_INIT_EL = "init.example.el"
+DOOM_UPSTREAM = "hlissner/doom-emacs"
+UPSTREAM_BRANCH = "develop"
+
+
+def create_pr(
+    repo: Repository,
+    pr_branch_name: str,
+    head: str,
+    file: ContentFile,
+    updated_content: str,
+    pr_title: str,
+    pr_body: str,
+):
+    try:
+        repo.get_branch(pr_branch_name)
+        print(f"Branch '{pr_branch_name}' already exist. Skipping update.")
+        return
+    except GithubException as ex:
+        if ex.status != 404:
+            raise
+
+    pr_branch = repo.create_git_ref(pr_branch_name, head)
+    repo.update_file(
+        file.path,
+        f"{pr_title}\n\n{pr_body}",
+        updated_content,
+        file.sha,
+        branch=pr_branch_name,
+    )
+    repo.create_pull(title=pr_title, body=pr_body, head=pr_branch.ref, base=BASE_BRANCH)
+
+
+def main():
+    if API_TOKEN:
+        github = Github(API_TOKEN)
+    else:
+        print("GITHUB_API_TOKEN is required")
+        sys.exit(1)
+
+    repo = github.get_repo(REPOSITORY)
+    head = repo.get_branch(BASE_BRANCH).commit.sha
+    init_el = cast(ContentFile, repo.get_contents(INIT_EL, ref=BASE_BRANCH))
+    doom_repo = github.get_repo(DOOM_UPSTREAM)
+    upstream_init_el = cast(
+        ContentFile, doom_repo.get_contents(UPSTREAM_INIT_EL, ref=UPSTREAM_BRANCH)
+    )
+
+    diff = "".join(
+        unified_diff(
+            init_el.decoded_content.decode().splitlines(keepends=True),
+            upstream_init_el.decoded_content.decode().splitlines(keepends=True),
+        )
+    )
+
+    if not diff:
+        print(f"{INIT_EL} is up-to date")
+        return
+
+    print(f"{INIT_EL} updated.")
+    print(diff)
+
+    upstream_rev = doom_repo.get_branch(UPSTREAM_BRANCH).commit.sha
+    title = f"{INIT_EL}: Updating from {DOOM_UPSTREAM} - {upstream_rev[:8]}"
+
+    body = f"""\
+### Changes for {INIT_EL}
+
+```diff
+{diff}
+```
+"""
+
+    print(f"[{INIT_EL}] - Creating PR\nTitle: {title}\nBody:\n{body}")
+    if DRY_RUN:
+        print(f"DRY-RUN: NOT creating PR...")
+        return
+
+    pr_branch_name = f"refs/heads/update/init.el-{upstream_rev}"
+    create_pr(
+        repo,
+        pr_branch_name,
+        head,
+        init_el,
+        upstream_init_el.decoded_content.decode(),
+        title,
+        body,
+    )
+
+
+if __name__ == "__main__":
+    main()