Add source archive and snippet to release (#1089)

Author: mortenmj

.github/workflows/create_archive_and_notes.sh

@@ -0,0 +1,53 @@
+#!/usr/bin/env bash
+# Copyright 2023 The Bazel Authors. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+set -o errexit -o nounset -o pipefail
+
+# Set by GH actions, see
+# https://docs.github.com/en/actions/learn-github-actions/environment-variables#default-environment-variables
+TAG=${GITHUB_REF_NAME}
+# A prefix is added to better match the GitHub generated archives.
+PREFIX="jsonnet-${TAG}"
+ARCHIVE="jsonnet-$TAG.tar.gz"
+git archive --format=tar --prefix=${PREFIX}/ ${TAG} | gzip > $ARCHIVE
+SHA=$(shasum -a 256 $ARCHIVE | awk '{print $1}')
+
+cat > release_notes.txt << EOF
+### Importing Jsonnet in a project that uses Bazel
+
+#### Using Bzlmod with Bazel 6
+
+Add to your \`MODULE.bazel\` file:
+
+\`\`\`starlark
+bazel_dep(name = "jsonnet", version = "${TAG}")
+\`\`\`
+
+#### Using WORKSPACE
+
+Paste this snippet into your \`WORKSPACE\` file:
+
+\`\`\`starlark
+load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
+
+http_archive(
+    name = "jsonnet",
+    sha256 = "${SHA}",
+    strip_prefix = "${PREFIX}",
+    url = "https://github.com/google/jsonnet/releases/download/${TAG}/jsonnet-${TAG}.tar.gz",
+)
+\`\`\`
+
+EOF

.github/workflows/release.yml

@@ -0,0 +1,38 @@
+# Copyright 2023 The Bazel Authors. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Cut a release whenever a new tag is pushed to the repo.
+name: Release
+
+on:
+  push:
+    tags:
+      - "*.*.*"
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+      - name: Create release archive and notes
+        run: .github/workflows/create_archive_and_notes.sh
+      - name: Release
+        uses: softprops/action-gh-release@v1
+        with:
+          # Use GH feature to populate the changelog automatically
+          generate_release_notes: true
+          body_path: release_notes.txt
+          fail_on_unmatched_files: true
+          files: jsonnet-*.tar.gz