Merge pull request silinternational#152 from silinternational/develop

Add flag for using the latest task definition
DjamesSuhanko · Aug 13, 2018 · 2470057 · 2470057
2 parents b23b574 + da39f64
commit 2470057
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Showing 2 changed files with 20 additions and 3 deletions.
diff --git a/README.md b/README.md
@@ -38,6 +38,7 @@ Usage
                                             Max definitions causes all task revisions not matching criteria to be deregistered, even if they're created manually.
                                             Script will only perform deregistration if deployment succeeds.
         --enable-rollback             Rollback task definition if new version is not running before TIMEOUT
+        --use-latest-task-def         Will use the most recently created task definition as it's base, rather than the last used.
         --force-new-deployment        Force a new deployment of the service. Default is false.
         --skip-deployments-check      Skip deployments check for services that take too long to drain old tasks
         --run-task                    Run created task now. If you set this, service-name are not needed.
@@ -114,7 +115,7 @@ _Naturally, enough computing resources must be available in the ECS cluster for
 Consequently, all that is needed to deploy a new version of an application is to update the Service which is running its
 Tasks to point at a new version of the Task Definition. `ecs-deploy` uses the python `aws` utility to do this. It,
 
-  * Pulls the JSON representation of the in-use Task Definition
+  * Pulls the JSON representation of the in-use Task Definition; or the most recently created if using `--use-latest-task-def`
   * Edits it
   * Defines a new version, with the changes
   * Updates the Service to use the new version

diff --git a/ecs-deploy b/ecs-deploy
@@ -15,6 +15,7 @@ VERBOSE=false
 TAGVAR=false
 TAGONLY=""
 ENABLE_ROLLBACK=false
+USE_MOST_RECENT_TASK_DEFINITION=false
 AWS_CLI=$(which aws)
 AWS_ECS="$AWS_CLI --output json ecs"
 FORCE_NEW_DEPLOYMENT=false
@@ -54,6 +55,7 @@ Optional arguments:
     --max-definitions            Number of Task Definition Revisions to persist before deregistering oldest revisions.
     --enable-rollback            Rollback task definition if new version is not running before TIMEOUT
     --force-new-deployment       Force a new deployment of the service. Default is false.
+    --use-latest-task-def   Will use the most recently created task definition as it's base, rather than the last used.
     --skip-deployments-check     Skip deployments check for services that take too long to drain old tasks
     --run-task                   Run created task now. If you set this, service-name are not needed.
     -v | --verbose               Verbose output
@@ -273,6 +275,17 @@ function getCurrentTaskDefinition() {
     if [ $SERVICE != false ]; then
       # Get current task definition arn from service
       TASK_DEFINITION_ARN=`$AWS_ECS describe-services --services $SERVICE --cluster $CLUSTER | jq -r .services[0].taskDefinition`
+      TASK_DEFINITION=`$AWS_ECS describe-task-definition --task-def $TASK_DEFINITION_ARN`
+
+      # For rollbacks
+      LAST_USED_TASK_DEFINITION_ARN=$TASK_DEFINITION_ARN
+
+      if [ $USE_MOST_RECENT_TASK_DEFINITION != false ]; then
+        # Use the most recently created TD of the family; rather than the most recently used.
+        TASK_DEFINITION_FAMILY=`$AWS_ECS describe-task-definition --task-def $TASK_DEFINITION_ARN | jq -r .taskDefinition.family`
+        TASK_DEFINITION=`$AWS_ECS describe-task-definition --task-def $TASK_DEFINITION_FAMILY`
+        TASK_DEFINITION_ARN=`$AWS_ECS describe-task-definition --task-def $TASK_DEFINITION_FAMILY | jq -r .taskDefinition.taskDefinitionArn`
+      fi
     elif [ $TASK_DEFINITION != false ]; then
       # Get current task definition arn from family[:revision] (or arn)
       TASK_DEFINITION_ARN=`$AWS_ECS describe-task-definition --task-def $TASK_DEFINITION | jq -r .taskDefinition.taskDefinitionArn`
@@ -330,8 +343,8 @@ function registerNewTaskDefinition() {
 }
 
 function rollback() {
-    echo "Rolling back to ${TASK_DEFINITION_ARN}"
-    $AWS_ECS update-service --cluster $CLUSTER --service $SERVICE --task-definition $TASK_DEFINITION_ARN > /dev/null
+    echo "Rolling back to ${LAST_USED_TASK_DEFINITION_ARN}"
+    $AWS_ECS update-service --cluster $CLUSTER --service $SERVICE --task-definition $LAST_USED_TASK_DEFINITION_ARN > /dev/null
 }
 
 function updateServiceForceNewDeployment() {
@@ -549,6 +562,9 @@ if [ "$BASH_SOURCE" == "$0" ]; then
             --enable-rollback)
                 ENABLE_ROLLBACK=true
                 ;;
+            --use-latest-task-def)
+                USE_MOST_RECENT_TASK_DEFINITION=true
+                ;;
             --force-new-deployment)
                 FORCE_NEW_DEPLOYMENT=true
                 ;;