Allow to trigger release manually (#1359)

.github/workflows/release-go.yml

@@ -1,6 +1,8 @@
 name: Create new Release
 
 on:
+  repository_dispatch:
+    types: perform-release
   schedule:
     - cron:  '0 9 * * 1'
 

DEVELOPMENT.md

@@ -8,6 +8,7 @@
 1. [Logging](#logging)
 1. [Error handling](#error-handling)
 1. [Debugging](#debugging)
+1. [Release](#release)
 
 ## Getting started
 
@@ -197,3 +198,11 @@ Modify the `launch.json` located in folder `.vscode` of your project root to poi
 ```
 
 Finally set your breakpoints and use the `Launch` button in the VS code UI to start debugging.
+
+## Release
+
+Releases are performed using [Project "Piper" Action](https://github.com/SAP/project-piper-action).
+We release on schedule (once a week) and on demand.
+To perform a release, the respective action must be invoked for which a convenience script is available in `contrib/perform-release.sh`.
+It requires a personal access token for GitHub with `repo` scope.
+Example usage `PIPER_RELEASE_TOKEN=THIS_IS_MY_TOKEN contrib/perform-release.sh`.

contrib/perform-release.sh

@@ -0,0 +1,18 @@
+#!/bin/sh -e
+
+# Manually trigger a release of project "Piper".
+# Usually we do release on a schedule, but sometimes you might need to trigger a release.
+# Invoke this script with PIPER_RELEASE_TOKEN set to your personal access token for GitHub with 'repo' scope.
+# This script is based on https://goobar.io/2019/12/07/manually-trigger-a-github-actions-workflow/
+
+if [ -z "$PIPER_RELEASE_TOKEN" ]
+then
+    echo "Required variable PIPER_RELEASE_TOKEN is not set, please set a personal access token for GitHub with 'repo' scope."
+    exit 1
+fi
+
+curl -H "Accept: application/vnd.github.everest-preview+json" \
+    -H "Authorization: token ${PIPER_RELEASE_TOKEN}" \
+    --request POST \
+    --data '{"event_type": "perform-release"}' \
+    https://api.github.com/repos/SAP/jenkins-library/dispatches