ecs_fargate_deploy_lambda.js

'use strict'
const AWS = require('aws-sdk')
AWS.config.region = 'us-east-1'

const ecrRegistryId = process.env.ECR_REGISTRY_ID
const ecrRegistryName = process.env.ECR_REGISTRY_NAME
const ecsName = process.env.ECS_NAME

const ecs = new AWS.ECS()
const ecr = new AWS.ECR()

exports.handler = async (event) => {
  const newVersion = event.version
  if (newVersion == '') {
    throw Error ('no version specified')
  }
  
  const image = await ecr.describeImages({
    registryId: ecrRegistryId,
    repositoryName: ecrRegistryName,
    imageIds: [
      { imageTag: newVersion }
    ]
  }).promise()
  if (image.imageDetails[0].imageSizeInBytes == 0) {
    throw Error ('no image in registry')
  }
  
  const cluster = await ecs.describeClusters({
    clusters: [ ecsName ]
  }).promise()
  if (cluster.clusters.length == 1) {
    if (cluster.clusters[0].status !== 'ACTIVE') {
      throw Error ('no ACTIVE cluster found')
    }
  } else {
    throw Error ('cluster not found')
  }

  const service = await ecs.describeServices({
    cluster: ecsName,
    services: [ ecsName ]
  }).promise()

  if (service.services.length == 1) {
    if (service.services[0].status !== 'ACTIVE') {
      throw Error ('no ACTIVE service found')
    }
  } else {
    throw Error ('service not found')
  }
  
  const taskDefinitions = await ecs.listTaskDefinitions({
    familyPrefix: ecsName,
    sort: 'DESC',
    status: 'active'
  }).promise()
  const lastTaskDefinition = await ecs.describeTaskDefinition({
    taskDefinition: taskDefinitions['taskDefinitionArns'][0],
    include: ['TAGS']
  }).promise()

  const newTaskDefintion = lastTaskDefinition.taskDefinition
  const newTaskDefintionTags = lastTaskDefinition.tags
  const newTaskDefintionContainerImage = lastTaskDefinition.taskDefinition.containerDefinitions[0].image.split(":").splice(0,1).concat([newVersion]).join(":")
  newTaskDefintion.containerDefinitions[0].image = newTaskDefintionContainerImage

  const extra_keys = [
    'taskDefinitionArn',
    'revision',
    'status',
    'requiresAttributes',
    'compatibilities'
  ]

  extra_keys.forEach(key => {
    delete newTaskDefintion[key]
  })
  
  for (const tag of newTaskDefintionTags) {
    if (tag['key'] == 'Version') {
      newTaskDefintion.tags.push({key: 'Version', value: newVersion})
    } else {
      newTaskDefintion.tags.push(tag)
    }
  }
  
  const registeredTaskDefinition = await ecs.registerTaskDefinition(newTaskDefintion).promise()
  
  const serviceUpdate = await ecs.updateService({
      cluster: ecsName,
      service: ecsName,
      taskDefinition: registeredTaskDefinition.taskDefinition.taskDefinitionArn
    }).promise()
  console.log(serviceUpdate)

  return {
    statusCode: 200,
    body: {
      status: 'success',
      version: newVersion
    }
  }  
}