Add release workflow (#121)

.bcr/source.template.json

@@ -1,5 +1,5 @@
 {
   "integrity": "",
-  "strip_prefix": "",
-  "url": "https://github.com/{OWNER}/{REPO}/releases/download/{TAG}/rules_jni-{TAG}.tar.gz"
+  "strip_prefix": "{REPO}-{VERSION}",
+  "url": "https://github.com/{OWNER}/{REPO}/releases/download/{TAG}/{REPO}-{TAG}.tar.gz"
 }

.github/workflows/release.yml

@@ -0,0 +1,15 @@
+# Cut a release whenever a new tag is pushed to the repo.
+# You should use an annotated tag, like `git tag -a v1.2.3`
+# and put the release notes into the commit message for the tag.
+name: Release
+
+on:
+  push:
+    tags:
+      - "v*.*.*"
+
+jobs:
+  release:
+    uses: bazel-contrib/.github/.github/workflows/release_ruleset.yaml@v7
+    with:
+      release_files: rules_jni-*.tar.gz

.github/workflows/release_prep.sh

@@ -0,0 +1,38 @@
+#!/usr/bin/env bash
+
+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=${GITHUB_REF_NAME}
+# The prefix is chosen to match what GitHub generates for source archives
+PREFIX="with_cfg.bzl-${TAG:1}"
+ARCHIVE="with_cfg.bzl-$TAG.tar.gz"
+git archive --format=tar --prefix=${PREFIX}/ ${TAG} | gzip > $ARCHIVE
+SHA=$(shasum -a 256 $ARCHIVE | awk '{print $1}')
+
+cat << EOF
+## Using Bzlmod
+
+1. Enable with \`common --enable_bzlmod\` in \`.bazelrc\`.
+2. Add to your \`MODULE.bazel\` file:
+
+\`\`\`starlark
+bazel_dep(name = "rules_jni", version = "${TAG:1}")
+\`\`\`
+
+## Using WORKSPACE
+
+Paste this snippet into your \`WORKSPACE.bazel\` file:
+
+\`\`\`starlark
+load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
+http_archive(
+    name = "rules_jni",
+    sha256 = "${SHA}",
+    strip_prefix = "${PREFIX}",
+    url = "https://github.com/fmeum/rules_jni/releases/download/${TAG}/${ARCHIVE}",
+)
+EOF
+
+echo "\`\`\`"