Add a workflow to create the changelog (#806)

* Add a workflow to create the changelog

This generates the changelog and creates a PR to update our file.

* Lint

* Fix ref

* Make it required

Author: therve

.github/workflows/prepare_release.yml

@@ -0,0 +1,84 @@
+name: Prepare release
+
+on:
+  workflow_dispatch:
+    inputs:
+      tag:
+        description: New version tag
+        required: true
+
+jobs:
+  prepare_release:
+    name: Create release PR
+    runs-on: ubuntu-latest
+    steps:
+      - name: Get GitHub App token
+        id: get_token
+        uses: tibdex/github-app-token@v1
+        with:
+          app_id: ${{ secrets.PIPELINE_GITHUB_APP_ID }}
+          private_key: ${{ secrets.PIPELINE_GITHUB_APP_PRIVATE_KEY }}
+      - name: Create PR
+        uses: actions/github-script@v5
+        env:
+          RELEASE_TAG: ${{ github.event.inputs.tag }}
+        with:
+          github-token: ${{ steps.get_token.outputs.token }}
+          script: |
+            const { data: notes } = await github.rest.repos.generateReleaseNotes({
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              tag_name: process.env.RELEASE_TAG,
+            });
+
+            const today = new Date().toJSON().slice(0, 10);
+            const header = [`# Changelog\n\n## ${process.env.RELEASE_TAG} / ${today}\n`];
+            const changes = header.concat(notes.body.split("\n").slice(3));
+
+            const { data: content } = await github.rest.repos.getContent({
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              path: "CHANGELOG.md",
+            });
+
+            const rawContent = Buffer.from(content.content, "base64")
+              .toString("utf-8")
+              .split("\n");
+            const newContent = changes.concat(rawContent.slice(1)).join("\n");
+
+            const { data: master } = await github.rest.git.getRef({
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              ref: "heads/master",
+            });
+            await github.rest.git.createRef({
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              ref: `refs/heads/release/${process.env.RELEASE_TAG}`,
+              sha: master.object.sha,
+            });
+
+            const { data: commit } = await github.rest.repos.createOrUpdateFileContents({
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              message: "Update CHANGELOG",
+              content: Buffer.from(newContent).toString("base64"),
+              path: "CHANGELOG.md",
+              branch: `release/${process.env.RELEASE_TAG}`,
+              sha: content.sha,
+            });
+
+            const { data: pr } = await github.rest.pulls.create({
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              head: `release/${process.env.RELEASE_TAG}`,
+              base: "master",
+              title: `Release ${process.env.RELEASE_TAG}`,
+              body: "Update CHANGELOG",
+            });
+            await github.rest.issues.addLabels({
+              issue_number: pr.number,
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              labels: ["changelog/no-changelog"],
+            });

.github/workflows/release.yml

@@ -1,16 +1,14 @@
-name: Build
+name: Release
 
 on:
-  pull_request:
   release:
     types:
       - published
 
 jobs:
-  build_wheels:
-    name: Build wheels on ${{ matrix.os }}
+  upload_release:
+    name: Upload release
     runs-on: ubuntu-20.04
-    if: github.event_name == 'release' && github.event.action == 'published'
     steps:
       - uses: actions/checkout@v2
         # Include all history and tags, needed for building the right version