A company just started to use AWS ECS/ECR for its dockerized applications. They are looking for a pipeline service with a source stage that can deploy a container application to the ECS cluster using a blue/green deployment. At the moment, all docker images are already stored in the ECR service which will be used in the pipelines as artifactories. What is the quickest way to implement this pipeline?

Answer options:

A.Create a Jenkins server in the EC2 instance. In the Jenkins job, add a source stage for the ECR docker image and a deployment stage for the ECS cluster using AWS CLI commands. 
B.In AWS CodePipeline, configure a source stage for ECR, a build stage with CodeBuild for the docker image and a deployment stage using CloudFormation to deploy the ECS cluster.
C.In AWS CodeDeploy, create a CodeDeploy application and a deployment group to configure the blue/green deployment to the ECS cluster using the image in the ECR repository.
D.In AWS CodePipeline, add a source stage for ECR docker image and a deployment stage for ECS where the deployment runs with a CodeDeploy application and deployment group.

Correct Answer – D
The question asks for the quickest way. So it is possible that multiple answers may work. However, we should find out the answer which is the most fit in this scenario without unnecessary efforts.
Option A is incorrect: Because CodePipeline is better in this case since it already provides a way for ECS blue/green deployment.
Option B is incorrect: Because using CloudFormation to deploy blue/green ECS services needs more effort and CodePipeline has already provided support for ECS deployment.
Option C is incorrect: Because AWS CodeDeploy cannot constitute a complete pipeline. The pipeline needs a source stage. When a new image is uploaded to Amazon ECR, the pipeline can automatically deploy container images.
Option D is CORRECT: Because a two-stages CodePipeline service can meet the need. In its deployment stage, the action provider can be selected as Amazon ECS (Blue/Green):