Indicate released image in the release body

Signed-off-by: Artiom Diomin <[email protected]>

.github/workflows/release.yaml

@@ -1,4 +1,4 @@
-name: Build and push a release image
+name: Build, push and release
 on:
   workflow_dispatch:
     inputs:
@@ -11,8 +11,18 @@ on:
         required: true
         type: string
 
+env:
+  IMAGE_REGISTRY: ghcr.io
+  IMAGE_REPO: gardener/ingress-gce
+  IMAGE_TAG: ${{ inputs.release_tag }}
+  PLATFORMS: linux/amd64,linux/arm64
+
+defaults:
+  run:
+    shell: bash
+
 jobs:
-  build-push:
+  build-push-release:
     permissions:
       # give GITHUB_TOKEN write permissions
       packages: write
@@ -34,25 +44,29 @@ jobs:
       - name: Login to registry
         uses: docker/login-action@9780b0c442fbb1117ed29e0efdff1e18412f7567 # https://github.com/docker/login-action/releases/tag/v3.3.0
         with:
-          registry: ghcr.io
+          registry: ${{ env.IMAGE_REGISTRY }}
           username: ${{ github.repository_owner }}
           password: ${{ secrets.GITHUB_TOKEN }}
 
       - name: Docker setup buildx
         uses: docker/setup-buildx-action@988b5a0280414f521da01fcc63a27aeeb4b104db # https://github.com/docker/setup-buildx-action/releases/tag/v3.6.1
         with:
-          platforms: linux/amd64,linux/arm64
+          platforms: ${{ env.PLATFORMS }}
 
       - name: Build and push Docker images
         uses: docker/build-push-action@5cd11c3a4ced054e52742c5fd54dca954e0edd85 # https://github.com/docker/build-push-action/releases/tag/v6.7.0
         with:
           context: .
           tags: |
-            ghcr.io/gardener/ingress-gce:${{ inputs.release_tag }}
+            ${{ env.IMAGE_REGISTRY }}/${{ env.IMAGE_REPO }}:${{ env.IMAGE_TAG }}
           push: true
-          platforms: linux/amd64,linux/arm64
+          platforms: ${{ env.PLATFORMS }}
 
       - name: Create new release
         uses: ncipollo/release-action@2c591bcc8ecdcd2db72b97d6147f871fcd833ba5 # https://github.com/ncipollo/release-action/releases/tag/v1.14.0
         with:
           tag: ${{ inputs.release_tag }}
+          makeLatest: true
+          body: |
+            ## Docker Images
+            * ingress-gce: ${{ env.IMAGE_REGISTRY }}/${{ env.IMAGE_REPO }}:${{ env.IMAGE_TAG }}

README.md

@@ -2,6 +2,45 @@
 
 [![reuse compliant](https://reuse.software/badge/reuse-compliant.svg)](https://reuse.software/)
 
+This repository is dedicated to building [kubernetes/ingress-gce](https://github.com/kubernetes/ingress-gce) images for Gardener project.
+
+## Building a new Release
+
+Once in a while a new release of the
+[kubernetes/ingress-gce](https://github.com/kubernetes/ingress-gce) will be
+released and we need to build new docker image. In order to trigger the new
+release one can use two options, tigger the release workflow from the web UI or
+from CLI, see more at the
+https://docs.github.com/en/actions/managing-workflow-runs-and-deployments/managing-workflow-runs/manually-running-a-workflow.
+
+
+### Trigger the release from the Github web UI
+
+* Navigate to Actions https://github.com/gardener/ingress-gce/actions
+* Select **Build, push and release** worflow
+* Click **Run worflow** button
+* Input `New release tag to publish` and `kubernetes/ingress-gce version to build`
+* Click green **Run worflow** button
+
+### Trigger the release from gh CLI
+
+```shell
+gh workflow run release.yaml -f release_tag=<NEW_TAG_TO_RELEASE> -f ingress_gce_version=<TAG_FROM_UPSTREAM>
+```
+
+Where `NEW_TAG_TO_RELEASE` is a new tag for the GH release and image to be
+created and `TAG_FROM_UPSTREAM` is existing target tag to build from
+[kubernetes/ingress-gce](https://github.com/kubernetes/ingress-gce).
+
+Example:
+
+```shell
+gh workflow run release.yaml -f release_tag=v1.30.0-sap.0 -f ingress_gce_version=v1.30.0
+```
+
+Will build [kubernetes/ingress-gce](https://github.com/kubernetes/ingress-gce) binary from v1.30.0 git tag, and publish docker image: `ghcr.io/gardener/ingress-gce:v1.30.0-sap.0`
+
+
 ## How to use this repository template
 
 This template repository can be used to seed new git repositories in the gardener github organisation.
@@ -99,5 +138,3 @@ In case you modify copied/forked source code you must state this in the header v
 To get your project reuse compliant you should register it [here](https://api.reuse.software/register) using your SAP email address. After confirming your email, an inital reuse check is done by the reuse API.
 
 To add the badge to your project's `README.md` file, use the snipped provided by the reuse API.
-
-##