Feat: Set Task Definitions to Inactive

README.md

@@ -96,6 +96,12 @@ Example: `"my-task"`
 
 ### Optional
 
+### `deregister-tasks` (boolean)
+
+Controls if previous task definitions are set to `INACTIVE` after a successful deploy. Default: `false`
+
+Requires the `ecs:DeregisterTaskDefinition` IAM Action
+
 #### `env` (array)
 
 An array of environment variables to add to *every* image's task definition in the `NAME=VALUE` format

hooks/command

@@ -156,6 +156,9 @@ if [ -n "${task_compat_reqs}" ]; then
   register_command+=(--requires-compatibilities "${task_compat_reqs}")
 fi
 
+# Task Deregistration Control
+task_deregistration=${BUILDKITE_PLUGIN_ECS_DEPLOY_DEREGISTER_TASKS:-false}
+
 echo "--- :ecs: register command:"
 
 json_output=$("${register_command[@]}")
@@ -185,7 +188,6 @@ aws ecs wait services-stable \
   --cluster "${cluster}" \
   --services "${service_name}" || deploy_exitcode=$?
 
-
 service_events=$(aws ecs describe-services \
   ${aws_default_args[@]+"${aws_default_args[@]}"} \
   --cluster "${cluster}" \
@@ -195,8 +197,12 @@ service_events=$(aws ecs describe-services \
 if [[ $deploy_exitcode -eq 0 ]]; then
   echo "--- :ecs: Service is up 🚀"
   echo "$service_events"
+
+  if [[ "${task_deregistration}" == "true" ]]; then
+    deregister_old_task_definitions "${task_family}" "${task_revision}"
+  fi
 else
   echo "+++ :ecs: Service failed to deploy ❌"
   echo "$service_events"
   exit $deploy_exitcode
-fi
+fi

lib/plugin.bash

@@ -53,3 +53,33 @@ function prefix_read_list_into_result() {
 function plugin_read_list_into_result() {
   prefix_read_list_into_result "BUILDKITE_PLUGIN_${PLUGIN_PREFIX}_${1}"
 }
+
+# Deregisters task definitions that are not the current one
+deregister_old_task_definitions() {
+  local task_family=$1
+  local task_revision=$2
+
+  echo "--- :ecs: Fetching old task definitions to de-register"
+  echo "$task_family"
+  # Fetch all `ACTIVE` task definitions for the family
+  all_active_task_defs=$(aws ecs list-task-definitions \
+    --family-prefix "${task_family}" \
+    --query 'taskDefinitionArns[]' \
+    --output text)
+
+  # Array
+  readarray -t active_task_defs <<<"$all_active_task_defs"
+
+  # Remove the current task definition from the list
+  for i in "${!active_task_defs[@]}"; do
+    if [[ "${active_task_defs[$i]}" == *":${task_revision}"* ]]; then
+      unset 'active_task_defs[$i]'
+    fi
+  done
+
+  # De-register the old task definitions
+  for task_def in "${active_task_defs[@]}"; do
+    echo "Deregistering $task_def"
+    aws ecs deregister-task-definition --task-definition "$task_def"
+  done
+}

plugin.yml

@@ -10,6 +10,8 @@ configuration:
       type: string
     container-definitions:
       type: string
+    deregister-tasks:
+      type: boolean
     env:
       type: array
     execution-role:

tests/command.bats

@@ -142,3 +142,25 @@ setup() {
 
   unstub aws
 }
+
+@test "Remove all but the current task definition" {
+  export BUILDKITE_PLUGIN_ECS_DEPLOY_DEREGISTER_TASKS=true
+
+  stub aws \
+      "ecs describe-task-definition --task-definition hello-world --query 'taskDefinition' : echo '{}'" \
+      "ecs register-task-definition --family hello-world --container-definitions \* : echo '{\"taskDefinition\":{\"revision\":2}}'" \
+      "ecs update-service --cluster my-cluster --service my-service --task-definition hello-world:2 : echo ok" \
+      "ecs wait services-stable --cluster my-cluster --services my-service : echo ok" \
+      "ecs describe-services --cluster my-cluster --services my-service --query 'services[].events' --output text : echo ok" \
+      "ecs list-task-definitions --family-prefix hello-world --query 'taskDefinitionArns[]' --output text : echo arn:aws:ecs:region:account:task-definition/hello-world:1" \
+      "ecs deregister-task-definition --task-definition arn:aws:ecs:region:account:task-definition/hello-world:1 : echo De-registering arn:aws:ecs:region:account:task-definition/hello-world:1"
+
+  run "$PWD/hooks/command"
+
+  assert_success
+  assert_output --partial "Service is up 🚀"
+  assert_output --partial "Fetching old task definitions to de-register"
+  assert_output --partial "Deregistering arn:aws:ecs:region:account:task-definition/hello-world:1"
+
+  unstub aws
+}