github: Add release workflows

This change implements two workflows that together implement the release
process. The first workflow is manually triggered, takes a
human-specified semver version string, and creates an automated commit
that updates the version string in the required places, and then tags
the new commit. The second workflow is triggered on release semver tags,
and performs the build and creates the release.

Tested: no - these workflows are hard to test manually, and will likely
require trial+error on Github itself.

Bug: linear/CUS-332

.bazelrc

@@ -20,3 +20,6 @@ build:noninteractive --show_timestamps
 build:noninteractive --announce_rc
 build:noninteractive --test_output=summary
 build:noninteractive --keep_going
+
+build:release --config=noninteractive
+build:release --stamp

.github/workflows/release.yml

@@ -0,0 +1,23 @@
+name: "release"
+
+on:
+  workflow_dispatch:
+    inputs:
+      version:
+        type: string
+        description: Version of engflow_auth to release
+        required: true
+
+permissions:
+  contents: write
+
+jobs:
+  release:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: release
+        run: |
+          infra/release.sh "${{ github.events.inputs.version }}"
+        env:
+          GITHUB_TOKEN: ${{ github.token }}

BUILD

@@ -2,3 +2,12 @@ load("@gazelle//:def.bzl", "gazelle")
 # gazelle:prefix github.com/EngFlow/auth
 
 gazelle(name = "gazelle")
+
+filegroup(
+    name = "release_artifacts",
+    srcs = [
+        "//cmd/engflow_auth:engflow_auth_linux_x64",
+        "//cmd/engflow_auth:engflow_auth_macos_arm64",
+        "//cmd/engflow_auth:engflow_auth_windows_x64",
+    ],
+)

cmd/engflow_auth/BUILD

@@ -1,4 +1,5 @@
 load("@rules_go//go:def.bzl", "go_binary", "go_cross_binary", "go_library", "go_test")
+load("//infra:visibility.bzl", "RELEASE_ARTIFACT")
 
 go_library(
     name = "engflow_auth_lib",
@@ -40,16 +41,19 @@ go_cross_binary(
     name = "engflow_auth_macos_arm64",
     platform = "@rules_go//go/toolchain:darwin_arm64_cgo",
     target = ":engflow_auth",
+    visibility = RELEASE_ARTIFACT,
 )
 
 go_cross_binary(
     name = "engflow_auth_windows_x64",
     platform = "@rules_go//go/toolchain:windows_amd64_cgo",
     target = ":engflow_auth",
+    visibility = RELEASE_ARTIFACT,
 )
 
 go_cross_binary(
     name = "engflow_auth_linux_x64",
     platform = "@rules_go//go/toolchain:linux_amd64_cgo",
     target = ":engflow_auth",
+    visibility = RELEASE_ARTIFACT,
 )

infra/release.sh

@@ -0,0 +1,67 @@
+#!/usr/bin/env bash
+
+set -o nounset -o pipefail -o errexit
+[[ "${SCRIPT_DEBUG:-"off"}" == "on" ]] && set -o xtrace
+
+if [[ "$#" -ne 1 ]]; then
+  echo "Want 1 argument; got $# arguments"
+  exit 1
+fi
+
+# Taken from https://semver.org/, with a `v` prepended
+readonly SEMVER_REGEX='^v(0|[1-9]\d*)\.(0|[1-9]\d*)\.(0|[1-9]\d*)(?:-((?:0|[1-9]\d*|\d*[a-zA-Z-][0-9a-zA-Z-]*)(?:\.(?:0|[1-9]\d*|\d*[a-zA-Z-][0-9a-zA-Z-]*))*))?(?:\+([0-9a-zA-Z-]+(?:\.[0-9a-zA-Z-]+)*))?$'
+readonly RELEASE_VERSION="$1"
+readonly GH_CLI_URL='https://github.com/cli/cli/releases/download/v2.52.0/gh_2.52.0_linux_amd64.tar.gz'
+readonly GH_CLI_EXPECTED_SHA256='3ea6ed8b2585f406a064cecd7e1501e58f56c8e7ca764ae1f3483d1b8ed68826'
+
+# Check that supplied version string follows semver
+if ! grep --quiet --extended-regexp "${SEMVER_REGEX}" <<<${RELEASE_VERSION}; then
+  echo "Supplied version string '${RELEASE_VERSION}' does not follow semver; exiting"
+  exit 1
+fi
+
+function cleanup {
+  rm -rf "${GH_CLI_DIR}"
+}
+
+# Download and verify Github CLI
+# TODO(CUS-353): Remove this after installing Github CLI in the self-hosted
+# environment (run via Docker?)
+readonly GH_CLI_DIR="$(mktemp -d -t 'gh_cli_XXXXXXXX')"
+curl --silent --location "${GH_CLI_URL}" \
+  | tee >(sha256sum - > "${GH_CLI_DIR}/archive_checksum.txt") \
+  | tar \
+      -C "${GH_CLI_DIR}" \
+      --strip-components 1 \
+      -xzf \
+      -
+trap 'cleanup' EXIT
+readonly GH_CLI="${GH_CLI_DIR}/bin/gh"
+readonly GH_CLI_ACTUAL_SHA256="$(cat ${GH_CLI_DIR}/archive_checksum.txt | awk '{ print $1 }')"
+if [[ "${GH_CLI_ACTUAL_SHA256}" != "${GH_CLI_EXPECTED_SHA256}" ]]; then
+    echo "SHA256 for Github CLI tarball ${GH_CLI_ACTUAL_SHA256} doesn't match expected value ${GH_CLI_ACTUAL_SHA256}; exiting"
+    exit 1
+fi
+
+# Check that the current commit is on either `main` or a release branch
+readonly EXPECTED_RELEASE_BRANCH="$(sed --regexp-extended 's|(v[0-9]+.[0-9]+).[0-9]+|release/\1|' <<<${RELEASE_VERSION})"
+if ! git branch \
+  --contains "$(git rev-parse HEAD)" \
+  | grep --quiet --extended-regexp "main|${EXPECTED_RELEASE_BRANCH}"; then
+    echo "Commit $(git rev-parse HEAD) is not on main or release branch ${EXPECTED_RELEASE_BRANCH}; exiting"
+    exit 1
+fi
+
+# Build release artifacts
+bazel build \
+    --config=release \
+    -- \
+    //:release_artifacts
+
+# Create release
+${GH_CLI} release create \
+    "v${RELEASE_VERSION}" \
+    --generate-notes \
+    "$(realpath bazel-out/k8-fastbuild-ST-*/bin/cmd/engflow_auth/engflow_auth_linux_x64)#engflow_auth (Linux, x64)" \
+    "$(realpath bazel-out/k8-fastbuild-ST-*/bin/cmd/engflow_auth/engflow_auth_macos_arm64)#engflow_auth (macOS, arm64)" \
+    "$(realpath bazel-out/k8-fastbuild-ST-*/bin/cmd/engflow_auth/engflow_auth_windows_x64)#engflow_auth (Windows, x64)"

infra/visibility.bzl

@@ -0,0 +1,5 @@
+"""Contains visibility constants to reduce duplication, increase BUILD file readability"""
+
+# Visibility used for artifacts that get released, which are defined by
+# filegroup(s) in the top-level BUILD file.
+RELEASE_ARTIFACT = ["//:__pkg__"]