<strong>A developer wants to use CodeBuild to build a docker image and push the image to ECR. Then CodePipeline uses CodeDeploy to deploy the latest docker image on EC2 clusters via ECS. </strong>

Answer options:

A.Pre-build stage: Nothing needs to be done as what you need to do is just push the image to ECR, which will be done in Post-build stage.
Post-build stage: Push the image to your ECR repository such as “docker push $REPOSITORY_URI:latest”.
B.Pre-build stage: Login into ECR using “aws ecr get-login” and set the repository URI. Post-build stage: Push the image to your ECR repository such as “docker push $REPOSITORY_URI:latest”.
C.Pre-build stage: Set the repository URI and an image tag if needed.
Post-build stage: Push the image to your ECR repository such as “docker push $REPOSITORY_URI:latest”.
D.Pre-build stage: Login into ECR using “aws ecr get-login” and set the repository URI. Post-build stage: Push the image to your ECR repository such as “aws ecr push $REPOSITORY_URI:latest”.

Correct Answer B
The below is an example of what the buildspec.yml should look like for this case:
Pre-build stage:
Log in to Amazon ECR.
Set the repository URI to your ECR image and add an image tag with the first seven characters of the Git commit ID of the source.
Build stage:
Build the Docker image and tag the image both as latest and with the Git commit ID.Post-build stage:
Push the image to your ECR repository with both tags.
Write a file called imagedefinitions.json in the build root that has your Amazon ECS service`s container name and the image and tag. The deployment stage of your CD pipeline uses this information to create a new revision of your service`s task definition, and then it updates the service to use the new task definition. The imagedefinitions.json file is required for the AWS CodeDeploy ECS job worker.
The details can be found in https://docs.aws.amazon.com/AmazonECS/latest/developerguide/ecs-cd-pipeline.html.
Option? ?A & C are ?incorrect because under Pre-build stage, you need to Log in to Amazon ECR and Set the repository URI.
Option? D? ?is? ?incorrect. Although the descriptions of Pre-build are correct, for Post-build stage, the CLI command should be “docker push $REPOSITORY_URI:latest”. Refer to https://docs.aws.amazon.com/cli/latest/reference/ecr/index.html for the supported ECR cli commands. After “aws ecr get-login” in the Pre-build stage, the following steps need the docker commands.