Add make prepare-release and automatic Github workflow (#1197)

* Add `make prepare-release` and automatic Github workflow

* patch

* patch

.github/workflows/release_drafter.yaml

@@ -0,0 +1,69 @@
+name: Prepare New Helm Chart Release
+
+# Description:
+# This workflow prepares a new release of the helm chart by updating chart and app versions as well as creating a PR.
+# A release PR will be created in these cases.
+#  - When a user kicks offs this workflow manually. A user can specify the CHART_VERSION and APP_VERSION used for the new release.
+#  - When the cron schedule kicks off the job and there is a major or minor version different for the APP_VERSION. The CHART_VERSION will be automatically incremented appropriately.
+
+on:
+  schedule:
+    # Run every 12 hours at 55 minutes past the hour.
+    - cron: "55 */12 * * *"
+  workflow_dispatch:
+    inputs:
+      CREATE_BRANCH:
+        description: 'Whether to create a remote branch for the release. Defaults to false since peter-evans/create-pull-request steps will handle branch creation.'
+        required: false
+        default: 'false'
+      CHART_VERSION:
+        description: 'Optionally overrides the chart version in Chart.yaml.'
+        required: false
+        default: ''
+      APP_VERSION:
+        description: 'Optionally overrides the app version in Chart.yaml.'
+        required: false
+        default: ''
+      DEBUG:
+        description: 'Enable debug mode for the script.'
+        required: false
+        default: 'false'
+
+jobs:
+  prepare_release:
+    runs-on: ubuntu-latest
+    env:
+      CREATE_BRANCH: ${{ github.event.inputs.CREATE_BRANCH }}
+      CHART_VERSION: ${{ github.event.inputs.CHART_VERSION }}
+      APP_VERSION: ${{ github.event.inputs.APP_VERSION }}
+      DEBUG: ${{ github.event.inputs.DEBUG }}
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Install tools
+        run: make install-tools
+
+      - name: Prepare Release
+        id: prepare_release
+        run: |
+          make prepare-release CHART_VERSION=$CHART_VERSION APP_VERSION=$APP_VERSION CREATE_BRANCH=$CREATE_BRANCH DEBUG=$DEBUG
+
+      - name: Check if PR is already open
+        id: check_if_pr_open
+        run: |
+          DIFF=1
+          git fetch origin
+          ((git show-ref --verify --quiet refs/heads/update-release) || (git diff --no-ext-diff --quiet main..update-release -- helm-charts)) && DIFF=0
+          echo "PR_NEEDED=$DIFF" >> "$GITHUB_OUTPUT"
+
+      - name: Open PR for Version Update
+        id: open_pr
+        if: ${{ steps.prepare_release.outputs.NEED_UPDATE == 1 && steps.check_if_pr_open.outputs.PR_NEEDED == 1 }}
+        uses: peter-evans/create-pull-request@v6
+        with:
+          commit-message: Prepare release v${{ steps.prepare_release.outputs.LATEST_CHART_VERSION }}
+          title: Prepare release v${{ steps.prepare_release.outputs.LATEST_CHART_VERSION }}
+          body: Updating Helm chart from version ${{ steps.prepare_release.outputs.CURRENT_CHART_VERSION }} to ${{ steps.prepare_release.outputs.LATEST_CHART_VERSION }} and App version from ${{ steps.prepare_release.outputs.CURRENT_APP_VERSION }} to ${{ steps.prepare_release.outputs.LATEST_APP_VERSION }}
+          branch: "update-release" # Same branch name for all PRs
+          base: main
+          delete-branch: true

Makefile

@@ -181,3 +181,15 @@ update-chart-dep: dep-update ## Updates the dependency version in the Chart.yaml
 		exit 1; \
 	fi
 	ci_scripts/update-chart-dependency.sh $(CHART_PATH) $(SUBCHART_NAME) $(DEBUG_MODE)
+
+# Usage Examples:
+#   make prepare-release
+#       - Prepares for a new release using the current chart and app version in Chart.yaml.
+#         Automatically increments the chart version.
+#         Commits and pushes changes to a new branch unless CREATE_BRANCH is set to "false".
+#   make prepare-release CHART_VERSION=1.2.3 APP_VERSION=1.2.0 CREATE_BRANCH=false
+#       - Prepares for a new release with the chart version explicitly set to 1.2.3 and the app version to 1.2.0.
+#         Changes remain local if CREATE_BRANCH is set to "false", suitable for workflows that do not immediately push to remote.
+.PHONY: prepare-release
+prepare-release: ## Prepares for a new release of the helm chart. Optionally specify CHART_VERSION and APP_VERSION.
+	ci_scripts/prepare-release.sh CREATE_BRANCH=${CREATE_BRANCH} CHART_VERSION=${CHART_VERSION} APP_VERSION=${APP_VERSION}

RELEASE.md

@@ -13,10 +13,24 @@ of `version` field.
 
 ### Release Procedure
 
-To make a new release of the helm chart:
-1. Bump the chart `version` in [Chart.yaml](helm-charts/splunk-otel-collector/Chart.yaml)
-1. Run `make render` to update Helm dependencies and render all the examples with the latest changes.
-1. Run `git add .` to stage the rendered differences without requiring a chloggen entry
-1. Run `make chlog-update` to update CHANGELOG.md for the release.
-1. Create PR and request review from the team.
-1. When the PR gets merged, the release will automatically be made and the helm repo updated.
+#### Using GitHub Workflows
+
+- **Manual Github Worfklow:**
+  - Navigate to the **[Draft Release](https://github.com/signalfx/splunk-otel-collector-chart/actions/workflows/release_drafter.yaml** workflow under GitHub Actions.
+  - Manually trigger the workflow. It automatically drafts a PR for the release.
+  - Review code changes, validate chart functionality, approve the PR, and merge the PR.
+- **Scheduled PRs:** Automatically generated PRs are scheduled for new versions of the collector that introduce major or minor version changes.
+  - Review code changes, validate chart functionality, approve the PR, and merge the PR.
+
+#### Manually Making a Release
+
+1. **Version Update:** Manually edit [Chart.yaml](helm-charts/splunk-otel-collector/Chart.yaml) to update the `version` field.
+1. **Dependencies & Rendering:** Execute `make render` to update Helm dependencies and apply changes.
+1. **CHANGELOG Update:** Run `make chlog-update` to incorporate changes into the CHANGELOG.
+1. **Stage & Commit Changes:**
+   1. Stage all changes: `git add .`
+   1. Commit with a message: `git commit -m "Prepare release {version}"`
+1. **Create a pull request:**
+   1. Push your commits to the signalfx owned remote repository.
+   1. Create a PR for your changes against the main branch.
+1. Review code changes, validate chart functionality, approve the PR, and merge the PR.

ci_scripts/base_util.sh

@@ -108,6 +108,7 @@ emit_output() {
     fi
 }
 
+# ---- CI/CD Methods ----
 # Function: setup_git
 # Description: Configures git so commits are published under the bot user.
 # Usage: setup_git
@@ -117,6 +118,80 @@ setup_git() {
   echo "set git config for release-bot ([email protected])"
 }
 
+# Function: get_release_version
+# Description: Removes the leading 'v' from a version string.
+# Usage: get_release_version "v1.2.3"
+get_release_version() {
+  local release_tag="$1"
+  echo "$release_tag" | cut -c2-
+}
+
+# Function: get_major_version
+# Description: Extracts the major version number from a version string.
+# Usage: get_major_version "v1.2.3"
+get_major_version() {
+  local release_tag="$1"
+  get_release_version "$release_tag" | awk -F'.' '{print $1}'
+}
+
+# Function: get_minor_version
+# Description: Extracts the minor version number from a version string.
+# Usage: get_minor_version "v1.2.3"
+get_minor_version() {
+  local release_tag="$1"
+  get_release_version "$release_tag" | awk -F'.' '{print $2}'
+}
+
+# Function: get_patch_version
+# Description: Extracts the patch version number from a version string.
+# Usage: get_patch_version "v1.2.3"
+get_patch_version() {
+  local release_tag="$1"
+  get_release_version "$release_tag" | awk -F'.' '{print $3}'
+}
+
+# Function: validate_version
+# Description: Validates that the provided version string follows the major.minor.patch format.
+# Usage: validate_version "1.2.3"
+validate_version() {
+  local version="$1"
+  if [[ ! $version =~ ^[0-9]+\.[0-9]+\.[0-9]+$ ]]
+  then
+    echo "Invalid release version: $version"
+    echo "Release version must follow the pattern major.minor.patch, e.g. 1.2.3"
+    exit 1
+  fi
+}
+
+# Function: setup_branch
+# Description: Checks if the specified branch exists and has open PRs. If it does and has no open PRs, it resets the branch to main. If it doesn't exist, it creates a new branch.
+# Usage: setup_branch "release-1.2.3" "github.com/example/repo"
+setup_branch() {
+  local branch="$1"
+  local repo_url="$2"
+
+  # check if the branch exists
+  if git ls-remote --exit-code --heads origin "$branch"; then
+    # get number of open PRs for the branch
+    pr_count="$( gh pr list --repo "$repo_url" --head "$branch" --state open --json id --jq length )"
+    if [[ ! "$pr_count" =~ ^[0-9]+$ ]]; then
+      echo "ERROR: Failed to get PRs for the $branch branch!" >&2
+      echo "$pr_count" >&2
+      exit 1
+    fi
+    if [[ "$pr_count" != "0" ]]; then
+      echo ">>> The $branch branch exists and has $pr_count open PR(s)."
+      echo ">>> Nothing to do."
+      exit 0
+    fi
+    echo ">>> Resetting the $branch branch to main ..."
+    git checkout "$branch"
+    git reset --hard origin/main
+  else
+    git checkout -b "$branch"
+  fi
+}
+
 # ---- Docker Methods ----
 # These methods provide functions for managing docker images.
 # To use this utility, source it in your script as shown in the example below:

ci_scripts/prepare-release.sh

@@ -0,0 +1,118 @@
+#!/bin/bash
+# Simplifies the process of preparing a new helm chart release.
+# Usage:
+# ./prepare-release.sh
+# Environment Variables:
+# CREATE_BRANCH - If set to "false", changes remain local. Default is "true" to push changes.
+# CHART_VERSION - Optionally overrides the chart version in Chart.yaml.
+# APP_VERSION - Optionally overrides the app version in Chart.yaml.
+
+# Include the base utility functions for setting and debugging variables
+SCRIPT_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
+source "$SCRIPT_DIR/base_util.sh"
+
+# Function to update Chart.yaml with the new chart and app version.
+function update_versions() {
+    echo "Updating Chart.yaml with chart version: $1 and app version: $2"
+    yq e ".version = \"$1\"" -i "${CHART_FILE_PATH}"
+    yq e ".appVersion = \"$2\"" -i "${CHART_FILE_PATH}"
+}
+
+# Function to notify Github workflows when to execute downstream release jobs.
+function notify_workflows_for_need_update() {
+    local current_chart_version="$1"
+    local latest_chart_version="$2"
+
+    # Emit the NEED_UPDATE variable to either GitHub output or stdout.
+    setd "NEED_UPDATE" 1
+    setd "CURRENT_CHART_VERSION" "$current_chart_version"
+    setd "LATEST_CHART_VERSION" "$latest_chart_version"
+    setd "CURRENT_APP_VERSION" "$current_chart_version"
+    setd "LATEST_APP_VERSION" "$latest_chart_version"
+
+    # Notify possible downstream CI/CD tasks about needed info.
+    emit_output "NEED_UPDATE"
+    emit_output "CURRENT_CHART_VERSION"
+    emit_output "LATEST_CHART_VERSION"
+    emit_output "CURRENT_APP_VERSION"
+    emit_output "LATEST_APP_VERSION"
+}
+
+# Prepare the release by updating versions, creating a branch, and committing changes.
+function prepare_release() {
+    local version="$1" appVersion="$2" create_branch="$3"
+
+    echo "Preparing release: $version"
+    echo "Release chart version: $version"
+    echo "Release app version: $appVersion"
+    # Update Chart.yaml with the new versions.
+    update_versions "$version" "$appVersion"
+
+    # Generate new configs and update the changelog.
+    make render
+    make chlog-update
+
+    # Stage any changes.
+    git add .
+
+    # Check if there are staged changes and if the create_branch flag is true.
+    if git diff --staged --quiet; then
+        echo "No changes to commit."
+    else
+        if [[ "$create_branch" == "true" ]]; then
+            local branch_name="release-$version"
+            echo "Creating branch: $branch_name"
+            # Ensure the branch is correctly set up, either by creating or resetting it.
+            setup_branch "$branch_name" "jvoravong/splunk-otel-collector-chart"
+            # Commit and push only if create_branch is true.
+            git commit -m "Prepare release $version"
+            git push -u origin "$branch_name"
+        else
+            echo "Changes are staged but not committed or pushed because CREATE_BRANCH is not set to true."
+            # Optionally, you might still want to commit locally even if not pushing.
+            git commit -m "Prepare release $version"
+        fi
+    fi
+}
+
+# Detect if CHART_VERSION is overridden via an environment variable.
+CHART_VERSION_OVERRIDDEN=false
+if [ -n "$CHART_VERSION" ]; then
+    CHART_VERSION_OVERRIDDEN=true
+    debug "Chart version overridden to: $CHART_VERSION"
+fi
+
+# Fetch chart and app versions, either from environment variables or Chart.yaml.
+CHART_VERSION=${CHART_VERSION:-$(grep "^version:" "${CHART_FILE_PATH}" | awk '{print $2}')}
+APP_VERSION=${APP_VERSION:-$(yq e ".appVersion" "${CHART_FILE_PATH}")}
+# Defaults CREATE_BRANCH to true if not set.
+CREATE_BRANCH=${CREATE_BRANCH:-true}
+
+# Increment chart version if it matches the app version's major and minor.
+chart_major=$(get_major_version "v$CHART_VERSION")
+chart_minor=$(get_minor_version "v$CHART_VERSION")
+app_major=$(get_major_version "v$APP_VERSION")
+app_minor=$(get_minor_version "v$APP_VERSION")
+
+# Notify downstream Github workflow to create a release PR if needed.
+# Create a PR if the job was manually created by a human.
+if [[ "$WORKFLOW_TRIGGER_TYPE" = "dispatch" ]]; then
+    notify_workflows_for_need_update "$CHART_VERSION" "$APP_VERSION"
+fi
+
+# Conditional logic to increment chart version or align it based on app version.
+if [[ "$CHART_VERSION_OVERRIDDEN" = true ]]; then
+    debug "Using overridden chart version: $CHART_VERSION"
+elif [[ "$chart_major" -eq "$app_major" && "$chart_minor" -eq "$app_minor" ]]; then
+    chart_patch=$(get_patch_version "v$CHART_VERSION")
+    CHART_VERSION="$chart_major.$chart_minor.$((chart_patch + 1))"
+    debug "Incrementing chart version to $chart_version"
+else
+    CHART_VERSION="$app_major.$app_minor.0"
+    debug "Aligning chart version to $chart_version due to major.minor mismatch with app version"
+    # Notify downstream Github workflow to create a release PR if needed.
+    # Create a PR if the there is a major or minor version difference for the chart.
+    notify_workflows_for_need_update "$CHART_VERSION" "$APP_VERSION"
+fi
+
+prepare_release "$CHART_VERSION" "$APP_VERSION" "$CREATE_BRANCH"