ecs

#!/bin/bash

set -o pipefail  # trace ERR through pipes
set -o errtrace  # trace ERR through 'time command' and other functions
# set -o nounset   ## set -u : exit the script if you try to use an uninitialised variable
set -o errexit   ## set -e : exit the script if any statement returns a non-true return value


function aws_setup {
    if [ -z ${AWS_REGION+x} ]; then
        AWS_REGION=$(aws configure get region)
    fi
    if [ -z ${AWS_ACCOUNT_ID+x} ]; then
        AWS_ACCOUNT_ID=$(aws ec2 describe-security-groups --query 'SecurityGroups[0].OwnerId' --output text)
    fi
    if [ -z ${ECR_REGISTRY+x} ]; then
        ECR_REGISTRY="${AWS_ACCOUNT_ID}.dkr.ecr.${AWS_REGION}.amazonaws.com"
    fi
    if [ -z ${AWS_LOGGED_IN+x} ]; then
        $(aws ecr get-login --no-include-email)
        AWS_LOGGED_IN=1
    fi
}

function sourceDestinationInput {
    # $1 is source as NAME:TAG
    assert_name_tag_arg "Source NAME:TAG must be specified" $1
    SOURCE_APP=${1%:*}
    SOURCE_TAG=${1#*:}
    SOURCE="$1"

    # $2 is dest as NAME[:TAG]
    assert_arg "Destination ECR_REPRO_NAME[:TAG] must be specified" $2
    if [[ $2 == *":"* ]]; then
        DEST_REPRO=${2%:*}
        DEST_TAG=${2#*:}
    else
        DEST_REPRO="$2"
        DEST_TAG="${SOURCE_APP}_${SOURCE_TAG}"
    fi
}

function push {

    sourceDestinationInput $1 $2

    # Check if we can identify remote ECR repository
    aws_setup

    # Tag for remote ECR repository
    docker tag "${SOURCE}" "${ECR_REGISTRY}/${DEST_REPRO}:${DEST_TAG}"

    # push to remote ECR repository
    docker push "${ECR_REGISTRY}/${DEST_REPRO}"

    #Remove tags for image to avoid re-push
    docker rmi "${ECR_REGISTRY}/${DEST_REPRO}:${DEST_TAG}"

}

function pull {

    # $1 is source as NAME:TAG
    assert_name_tag_arg "Source ECR_REPRO_NAME:TAG must be specified" $1
    SOURCE="$1"

    # Check if we can identify remote ECR repository
    aws_setup

    # Pull from repro
    docker pull "${ECR_REGISTRY}/${SOURCE}"

}

function deploy {

    sourceDestinationInput $1 $2

    # use global vars created in sourceDestinationInput
    ECS_CLUSTER_NAME="${DEST_REPRO}"
    ECS_SERVICE_NAME="${SOURCE_APP}"
    ECS_TASK_DEFINITION_NAME="${ECS_CLUSTER_NAME}-${ECS_SERVICE_NAME}"

    # Get current task definition and update image to pushed TAG
    IMAGE="${ECR_REGISTRY}/${DEST_REPRO}:${DEST_TAG}"
    echo "Image: $IMAGE"
    CONTAINER_DEF=$( \
        aws ecs describe-task-definition --task-definition "${ECS_TASK_DEFINITION_NAME}" | \
        jq '.taskDefinition.containerDefinitions[0]' | \
        jq -r ".image= \"${IMAGE}\" " \
    )

    # Create new task revision using updated def
    aws ecs register-task-definition --family "${ECS_TASK_DEFINITION_NAME}" --container-definitions "${CONTAINER_DEF}"

    # Update service using old def
    aws ecs update-service --cluster "${ECS_CLUSTER_NAME}" --service "${ECS_SERVICE_NAME}"  --task-definition "${ECS_TASK_DEFINITION_NAME}"

}

function container {
    # $1 is container name, $2 is cluster name
    assert_arg "Container name must be specified" $1
    assert_arg "Cluster name must be specified" $2
    ECS_TASK_DEFINITION_NAME="$2-$1"

    CONTAINER_DEF=$( \
        aws ecs describe-task-definition --task-definition "${ECS_TASK_DEFINITION_NAME}" | \
        jq '.taskDefinition.containerDefinitions[0]' \
    )
    echo "$CONTAINER_DEF" >&2
}

function image {
    # $1 is container name, $2 is cluster name
    assert_arg "Container name must be specified" $1
    assert_arg "Cluster name must be specified" $2
    ECS_TASK_DEFINITION_NAME="$2-$1"

    IMAGE=$( \
        aws ecs describe-task-definition --task-definition "${ECS_TASK_DEFINITION_NAME}" | \
        jq '.taskDefinition.containerDefinitions[0].image' \
    )
    echo "$IMAGE" >&2
}

function docker_build {

    assert_arg "Container name must be specified" $1

    if [ -e pom.xml ]; then
        mvn clean install
    fi

    CONTAINER_NAME=$1
    GIT_STATUS=$(git status -s)
    GIT_BRANCH=$(git rev-parse --abbrev-ref HEAD)
    GIT_COMMIT=$(git show -s --format='%h')
    # Retrieving TAG may return error and contain non valid repro characters. Lets do later...
    # GIT_TAG=$(git describe --exact-match "$GIT_COMMIT")

    if [[ ! -z $GIT_STATUS ]]; then
        echo "Has staged uncommited files"
        TAG="${GIT_BRANCH}-${GIT_COMMIT}-SNAPSHOT"
    else
        if [[ ! -z $GIT_TAG ]]; then
            TAG="${GIT_BRANCH}-${GIT_COMMIT}-${GIT_TAG}"
        else
            TAG="${GIT_BRANCH}-${GIT_COMMIT}"
        fi
    fi

    # Build local image
    docker build -t "${CONTAINER_NAME}:${TAG}" .

    # Remove all dangling images (without name,tags)
    DANGLING=$(docker images -f dangling=true -q)
    if [[ ! -z $DANGLING ]]; then
        docker rmi -f $DANGLING
    fi

    # If repro name is supplied, lets push image
    if [[ ! -z $2 ]]; then
        echo "push to  $2"
        push "${CONTAINER_NAME}:${TAG}" $2
        echo "image tag: ${CONTAINER_NAME}_${TAG}"
    fi

    # lets list all images with container name to remind user to clean-up...
    docker images "${CONTAINER_NAME}*"

}


function repositories {
    aws ecr describe-repositories | jq -r "[.repositories[].repositoryName]"
}

function clusters {
    aws ecs list-clusters | jq -r ".clusterArns"
}

function services {
    # Cluster must be specified
    if [ -z ${CLUSTER+x} ]; then
        echo "-c CLUSTER_SHORT_NAME must be specified using the services command!"
        exit 1
    fi
    aws ecs list-services --cluster "$CLUSTER" | jq -r ".serviceArns"
}

function assert_arg {
    if [ -z ${2+x} ]; then
        echo "$1" >&2
        exit 1
    fi
}

function assert_name_tag_arg {
    assert_arg $1 $2
    if [[ $2 != *":"* ]]; then
        echo "$1" >&2
        exit 1
    fi
}

case "$1" in
    push)
        push $2 $3
        ;;
    pull)
        pull $2
        ;;
    deploy)
        deploy $2 $3
        ;;
    container)
        container $2 $3
        ;;
    image)
        image $2 $3
        ;;
    repositories)
        repositories
        ;;
    clusters)
        clusters
        ;;
    build)
        docker_build $2 $3
        ;;
    services)
        shift;
        while getopts ":c::" opt; do
          case $opt in
            c)
              CLUSTER="$OPTARG"
              ;;
            \?)
              echo "Invalid option for services: -$OPTARG" >&2
              exit 1
              ;;
            :)
              echo "Option -$OPTARG requires an argument." >&2
              exit 1
              ;;
          esac
        done
        services
        ;;
    *)
        echo "Invalid command: $1"
        echo $"Usage: $0 {push|pull|deploy|repositories|clusters|services}"
        exit 1
        ;;
esac