Improve release process (polkadot-fellows#63)

* Improve release process

This pull request introduces the `changelog-processor.py`. A small
script for getting some information out of the `CHANGELOG.md` file for
improving the release process. The script supports to get the latest
version in the `CHANGELOG.md` file, aka the version top of the
file. (This could also be `Unreleased`) The other command is for
printing if there should be done a release or not. This is decided based
on the latest version and if there exists a tag for it.

* Use correct syntax

* Single quotes..

* Integer?

* 🤦

* This?

* AHH

* Some last improvements

* Update .github/changelog-processor.py

Co-authored-by: Oliver Tale-Yazdi <[email protected]>

* Apply suggestions from code review

* Make the arguments mutally exclusive

---------

Co-authored-by: Oliver Tale-Yazdi <[email protected]>

.github/changelog-processor.py

@@ -0,0 +1,65 @@
+#!/usr/bin/env python
+
+import os
+import sys
+import argparse
+
+parser = argparse.ArgumentParser(description="Process the CHANGELOG.md")
+parser.add_argument(
+    "changelog",
+    metavar="CHANGELOG",
+    help="Path to the CHANGELOG.md file",
+    default="CHANGELOG.md",
+    nargs='?'
+)
+
+group = parser.add_mutually_exclusive_group()
+group.add_argument(
+    "--print-latest-version",
+    dest="print_latest_version",
+    help="Print the latest version (first in the file) found in the CHANGELOG.md",
+    action="store_true"
+)
+group.add_argument(
+    "--should-release",
+    dest="should_release",
+    help="Should a release be made? Prints `1` or `0`.",
+    action="store_true"
+)
+
+args = parser.parse_args()
+
+with open(args.changelog, "r") as changelog:
+    lines = changelog.readlines()
+
+    # Find the latest version
+    for line in lines:
+        if not line.startswith("## ["):
+            continue
+
+        version = line.strip().removeprefix("## [").split("]")[0]
+        break
+
+    if args.print_latest_version:
+        print(version, end = "")
+        sys.exit(0)
+    elif args.should_release:
+        if version.lower() == "unreleased":
+            print("0", end = "")
+            sys.exit(-1)
+        elif version.count(".") != 2:
+            print("0", end = "")
+            sys.exit(-1)
+
+        stream = os.popen("git tag -l v" + version)
+        output = stream.read()
+
+        # Empty output means that the tag doesn't exist and that we should release.
+        if output.strip() == "":
+            print("1", end = "")
+        else:
+            print("0", end = "")
+
+        sys.exit(0)
+    else:
+        parser.print_help()

.github/workflows/release.yml

@@ -7,7 +7,21 @@ on:
   workflow_dispatch:
 
 jobs:
+  collect-release-information:
+    runs-on: ubuntu-latest
+    outputs:
+      should-release: ${{ steps.run.outputs.should-release }}
+      version: ${{ steps.run.outputs.version }}
+    steps:
+      - uses: actions/checkout@v2
+      - id: run
+        run: |
+          echo "should-release=$(.github/changelog-processor.py CHANGELOG.md --should-release)" >> $GITHUB_OUTPUT
+          echo "version=$(.github/changelog-processor.py CHANGELOG.md --print-latest-version)" >> $GITHUB_OUTPUT
+          cat $GITHUB_OUTPUT
   runtime-matrix:
+    needs: [ collect-release-information ]
+    if: needs.collect-release-information.outputs.should-release == '1'
     runs-on: ubuntu-latest
     outputs:
       runtime: ${{ steps.runtime.outputs.runtime }}
@@ -66,9 +80,9 @@ jobs:
           path: |
             ${{ steps.srtool_build.outputs.wasm_compressed }}
 
-  publish-draft-release:
+  publish-release:
     runs-on: ubuntu-latest
-    needs: [ build-runtimes ]
+    needs: [ build-runtimes, collect-release-information ]
     outputs:
       release_url: ${{ steps.create-release.outputs.html_url }}
       asset_upload_url: ${{ steps.create-release.outputs.upload_url }}
@@ -92,7 +106,6 @@ jobs:
           SRTOOL() { <$(<<<$CONTEXT head -n1) jq -r .$1; }
           WASM() { <${JSON} jq -r ".runtimes.compressed.subwasm.$1"; }
           tee -a DRAFT <<-EOF
-          ## Changelog
           EOF
           tee -a DRAFT <CHANGELOG.md
           tee -a DRAFT <<-EOF
@@ -115,19 +128,19 @@ jobs:
           EOF
           done
 
-      - name: Create draft release
+      - name: Create release
         id: create-release
         uses: actions/create-release@v1
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         with:
-          tag_name: ${{ github.ref }}
-          release_name: Runtimes ${{ github.sha }}
+          tag_name: ${{ format('v{0}', needs.collect-release-information.outputs.version) }}
+          release_name: Runtimes ${{ needs.collect-release-information.outputs.version }}
           body_path: DRAFT
-          draft: true
+          draft: false
 
   publish-runtimes:
-    needs: [ runtime-matrix, publish-draft-release ]
+    needs: [ runtime-matrix, publish-release ]
     continue-on-error: true
     runs-on: ubuntu-latest
     env:

CHANGELOG.md

@@ -2,7 +2,9 @@
 
 Changelog for the runtimes governed by the Polkadot Fellowship.
 
-## [1.0.0]
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
+
+## [Unreleased]
 
 ### Changed
 

README.md

@@ -36,3 +36,14 @@ To use it, write a comment in a PR that says:
 This will enable [`auto-merge`](https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/incorporating-changes-from-a-pull-request/automatically-merging-a-pull-request) in the Pull Request (or merge it if it is ready to merge).
 
 The automation can be triggered by the author of the PR or any fellow whose GitHub handle is part of their identity.
+
+# Release process
+
+Releases are automatically pushed on commits merged to master that fulfill the following requirements:
+
+- The [`CHANGELOG.md`](CHANGELOG.md) file was modified.
+- The latest version (the version at the top of the file) in [`CHANGELOG.md`](CHANGELOG.md) has no tag in the repository.
+
+The release process is building all runtimes and then puts them into a release in this github repository.
+
+The format of [`CHANGELOG.md`](CHANGELOG.md) is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).