feat(go): runtime release tagging (#2417)

Adds github actions workflows for automatically tagging jsii-runtime-go
when jsii release branch is updated. This essentially publishes new
runtime version. This may eventually be served better in delivlib but is
much simpler in github actions for the alpha phase.

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Romain Marcadier <[email protected]>

.github/workflows/main.yml

@@ -466,3 +466,95 @@ jobs:
           path: |-
             ${{ github.workspace }}/aws-cdk/dist/
             ${{ github.workspace }}/aws-cdk/**/dist/
+
+  push-go-runtime:
+    needs: build
+    if: github.event_name == 'push'
+    runs-on: ubuntu-latest
+    steps:
+      - name: Set up Node 12
+        uses: actions/[email protected]
+        with:
+          node-version: '12'
+      - name: Download Artifact
+        uses: actions/download-artifact@v2
+        with:
+          name: built-tree
+          path: ${{ github.workspace }}/jsii-built-tree
+      - name: Extract Artifact
+        working-directory: ${{ github.workspace }}/jsii-built-tree
+        run: |-
+          echo "::group::Untar Archive"
+          tar Jxvf built-tree.tar.xz
+          echo "::endgroup"
+
+          rm built-tree.tar.xz
+      - name: Get Last Commit Message
+        id: get-last-commit-msg
+        working-directory: ${{ github.workspace }}/jsii-built-tree
+        run: |-
+          message=$(git log -1 --format=%s)
+          echo "::set-output name=result::$message"
+      - name: Locate Caches
+        id: cache-locations
+        run: |-
+          echo "::set-output name=yarn-cache::$(yarn cache dir)"
+      - name: Cache
+        uses: actions/cache@v2
+        with:
+          path: |-
+            ${{ steps.cache-locations.outputs.yarn-cache }}
+            ${{ github.workspace }}/node_modules
+            ${{ github.workspace }}/*/*/node_modules
+          key: ${{ hashFiles('**/yarn.lock') }}
+          restore-keys: |-
+            ${{ runner.os }}-yarn-
+      - name: Install Dependencies
+        working-directory: ${{ github.workspace }}/jsii-built-tree
+        run: |-
+          yarn install --frozen-lockfile
+      - name: Build Runtime Repo Directory
+        id: build-repo-dir
+        run: |-
+          mkdir ${{ github.workspace }}/jsii-runtime-go
+          repo_dir=${{ github.workspace }}/jsii-runtime-go
+          echo "::set-output name=repodir::$repo_dir"
+      - name: Clone Runtime
+        uses: actions/checkout@v2
+        with:
+          repository: ${{ secrets.JSII_RUNTIME_REPO_NAME }}
+          ref: 'main'
+          token: ${{ secrets.AUTO_APPROVE_GITHUB_TOKEN }}
+          path: ${{ steps.build-repo-dir.outputs.repodir }}
+      - name: Copy Runtime Files
+        working-directory: ${{ github.workspace }}/jsii-built-tree/packages/@jsii/go-runtime
+        run: |-
+          yarn ts-node ./build-tools/build-repo-dir.ts ${{ steps.build-repo-dir.outputs.repodir }}
+      - name: Check for changes
+        id: check-for-changes
+        working-directory: ${{ steps.build-repo-dir.outputs.repodir }}
+        run: |-
+          git fetch --depth=1 --quiet origin main
+          git add .
+          # Check for modifications in tracked files
+          changed=$(git diff --name-only origin/main)
+          if [-z "$changed"]; then
+            echo "::set-output name=result::false"
+          else
+            echo "::set-output name=result::true"
+          fi
+      - name: Commit and Push
+        if: steps.check-for-changes.outputs.result == 'true'
+        working-directory: ${{ steps.build-repo-dir.outputs.repodir }}
+        run: |-
+          git config user.name "AWS CDK Automation"
+          git config user.email "[email protected]"
+          git commit -m "${{ steps.get-last-commit-msg.outputs.result }}"
+          git push
+      - name: Tag Release
+        if: github.ref == 'refs/head/release'
+        run: |-
+          VERSION=$(node -e 'console.log(require("./lerna.json").version)')
+          cd ${{ steps.build-repo-dir.outputs.repodir }}
+          git tag -a $VERSION -m "v$VERSION"
+          git push $VERSION

packages/@jsii/go-runtime/build-tools/build-repo-dir.ts

@@ -1,21 +1,10 @@
 #!/usr/bin/env npx ts-node
 
-import { SpawnOptions } from 'child_process';
 import * as fs from 'fs-extra';
 import * as path from 'path';
 
-import { runCommand } from './_constants';
-
 // Constants
 const RUNTIME_DIR = path.resolve(__dirname, '..', 'jsii-experimental');
-// Destination repo configuration
-const REPO_NAME = process.env.JSII_RUNTIME_REPO_NAME;
-const USERNAME = process.env.JSII_RUNTIME_REPO_USERNAME;
-const TOKEN = process.env.JSII_RUNTIME_REPO_TOKEN;
-const REMOTE =
-  USERNAME && TOKEN
-    ? `https://${USERNAME}:${TOKEN}@github.com/${REPO_NAME}.git`
-    : `https://github.com${REPO_NAME}.git`;
 
 // Always preserve these files/paths from the cloned repo
 const PRESERVE = ['.git', '.gitignore'];
@@ -28,18 +17,10 @@ const DONT_OVERWRITE = [...PRESERVE, ...ROOT_FILES, ...LOCAL_FILES];
 
 async function main() {
   const args = process.argv.slice(2);
-  console.log(args[0]);
   await makeRepoDir(args[0]);
 }
 
 async function makeRepoDir(dir: string) {
-  const runRepoCmd = (
-    cmd: string,
-    args: readonly string[],
-    opts: SpawnOptions = {},
-  ) => runCommand(cmd, args, { cwd: dir, ...opts });
-  runRepoCmd('git', ['clone', REMOTE, '.'], { stdio: 'inherit' });
-
   // Clone repo and delete its contents except nodes in the PRESERVE list.
   const clonedFiles = await fs.readdir(dir);
   await Promise.all(