Github Action Rollback Strategy - github

Question

I am trying to create a rollback strategy for ecs task that managed with github action. What i am trying to do is:
if previous task definition's image is not found on ecr, set revision number-=1 and check one more previous task definition image, until it is found a valid image (imagetag actually but it doesnt matter.)
If previous task definition revision number is not found check previous (previous revision number -1 like above) revision until found a valid one.
According to that target: when id:tag-checker step is hit on else block i need to repeat all the step below from id:previous-revision-image-tag until my if else blocks pass with true fields.
So how can i achieve this purpose with github action?
Basically i want to repeat all the steps and below steps from a step that i pick.
name: AWS Rollback
on:
workflow_dispatch:
env:
AWS_REGION: "region"
ECR_REPOSITORY: "nodejs-1"
ECS_SERVICE: "nodejs-service"
ECS_CLUSTER: "test-1"
ECS_TASK_DEFINITION: ".aws/staging.paris.json"
CONTAINER_NAME: "nodejs-test"
jobs:
Rollback:
name: "Rollback"
runs-on: ubuntu-latest
environment: production
steps:
- name: Configure AWS credentials
uses: aws-actions/configure-aws-credentials#v1
with:
aws-access-key-id: ${{ secrets.AWS_ACCESS_KEY_ID }}
aws-secret-access-key: ${{ secrets.AWS_SECRET_ACCESS_KEY }}
aws-region: ${{ env.AWS_REGION }}
- name: Login to Amazon ECR
id: login-ecr
uses: aws-actions/amazon-ecr-login#v1
- name: Set Current Task Revision
id: current-revision
env:
ECR_REGISTRY: ${{ steps.login-ecr.outputs.registry }}
IMAGE_TAG: ${{ steps.date.outputs.date }}-${{ steps.vars.outputs.sha_short }}
run: |
echo "REVISION_NUMBER=$(aws ecs describe-services --cluster ${{ env.ECS_CLUSTER }} --query "services[].taskDefinition" --services ${{ env.ECS_SERVICE }} --output text | cut -d: -f7)" >> $GITHUB_ENV
echo "REVISION_NAME=$(aws ecs describe-services --cluster ${{ env.ECS_CLUSTER }} --query "services[].taskDefinition" --services ${{ env.ECS_SERVICE }} --output text | cut -d: -f1-6)" >> $GITHUB_ENV
- name: Set Previous Task Revision Number
id: previous-revision-number
run: |
echo "PREVIOUS_REVISION_NUMBER"=$((${{ env.REVISION_NUMBER }}-1)) >> $GITHUB_ENV
- name: Set Previous Task Revision Image Tag
id: previous-revision-image-tag
env:
PREVIOUS_REVISION_NUMBER: ${{ env.PREVIOUS_REVISION_NUMBER }}
run: |
echo "IMAGE_TAG"=$(aws ecs describe-task-definition --task-definition "${{ env.ECR_REPOSITORY }}:$PREVIOUS_REVISION_NUMBER" --query "taskDefinition.containerDefinitions[0].image" --output text |cut -d: -f2) >> $GITHUB_ENV
- name: Check if previous revision image is exist or not
id: tag-checker
env:
IMAGE_TAG: ${{ env.IMAGE_TAG }}
run: |
if (aws ecr describe-images --repository-name=${{ env.ECR_REPOSITORY }} --image-ids=imageTag=$IMAGE_TAG &> /dev/null); then
echo "Image Found"
else
echo 'Image is Not Found'
fi
- name: Check if previous task revision exist or not
id: revision-checker
env:
PREVIOUS_REVISION_NUMBER: ${{ env.PREVIOUS_REVISION_NUMBER }}
run: |
if (aws ecs describe-task-definition --task-definition "${{ env.ECR_REPOSITORY }}:$PREVIOUS_REVISION_NUMBER" --output text &> /dev/null); then
echo "Task definition Found"
else
echo 'Task definition not Found'
fi
# - name: Rollback to previous version
# id: rollback
# run: |
# aws ecs update-service --cluster ${{ env.ECS_CLUSTER }} --service ${{ env.ECS_SERVICE }} --task-definition ${{ env.REVISION_NAME }}:${{ env.PREVIOUS_REVISION_NUMBER }}

Answer 1

I have a solution for you without updating revision and task.
Lets think you have a ecr repo with tags
latest
v1.0.2
v1.0.1
v1.0.0
latest point to your latest version (v1.0.2)
You need to update your ecs task definition you use latest version always.
When you want to rollback. You can do a hack on ECR point latest version to v1.0.1 then just invoke ecs to force re-deploy services.
IMAGE_TAG_YOU_WANT_TO_DEPLOY="v1.0.1"
# fetch v1.0.1 manifest
MANIFEST=$(aws ecr batch-get-image --repository-name ${ECR_REPOSITORY} --image-ids imageTag=${IMAGE_TAG_YOU_WANT_TO_DEPLOY} --output json | jq --raw-output --join-output '.images[0].imageManifest')
# move latest tag pointer to v1.0.1
aws ecr put-image --repository-name ${ECR_REPOSITORY} --image-tag latest --image-manifest "$MANIFEST"
aws ecs update-service --cluster ${ECS_CLUSTER} --service ${ECS_SERVICE} --force-new-deployment --region us-east-2
For new deployment you will create a image tag (v1.0.3 and latest) together and push both images to ECR.
then just invoke update-service only. (new latest is v1.0.3)
aws ecs update-service --cluster ${ECS_CLUSTER} --service ${ECS_SERVICE} --force-new-deployment --region us-east-2