[cdk-pipelines] Stacks in stage doesn't get deployed in parallel when stage.add_application is used?

❓ Parallel Deployment to Multiple Accounts

The Question

[1]: CDK Pipeline does not deploy the a stack in two accounts in parallel

environments = self.node.try_get_context("environments")
stage = pipeline.add_stage("dev")
stage.add_application(EpsRoute53(self, f"dev01-route53", env=environments["dev01"], account_identifier="dev01"))
stage.add_application(EpsRoute53(self, f"dev02-route53", env=environments["dev02"], account_identifier="dev02"))

Note, environments[“dev01”], - account, region combination

Result: The stack EpsRoute53 is getting ordered as follows

1. dev01-epsroute53.prepare
2. dev01-epsroute53.deploy
3. dev02-epsroute53.prepare
4. dev02-epsroute53.deploy

I had to change to using something like this to get it added pipeline stage actions in parallel.

environments = self.node.try_get_context("environments")
stage = pipeline.add_stage("dev")
stage.add_actions(pipelines.DeployCdkStackAction(action_role=iam.Role.from_role_arn(self, id="role-dev01",role_arn="arn:aws:iam::<account-dev01>:role/<pipeline-role-arn>"),
                                   stack_name="dev01-route53-domain-stack",
                                   template_path="<path of the template>",
                                   region="us-west-2",
                                   cloud_assembly_input=cloud_assembly_artifact,
                                   prepare_run_order=1,
                                   execute_run_order=2,
                                   cloud_formation_execution_role=iam.Role.from_role_arn(self, id="role-dev01a",
                                   role_arn="arn:aws:iam::<account-dev01>:role/cdk-XXXX-cfn-exec-role-<account-dev01>-us-west-2")
                                   )))
stage.add_actions(pipelines.DeployCdkStackAction(action_role=iam.Role.from_role_arn(self, id="role-dev01",role_arn="arn:aws:iam::<account-dev02>:role/<pipeline-role-arn>"),
                                   stack_name="dev02-route53-domain-stack",
                                   template_path="<path of the template>",
                                   region="us-west-2",
                                   cloud_assembly_input=cloud_assembly_artifact,
                                   prepare_run_order=1,
                                   execute_run_order=2,
                                   cloud_formation_execution_role=iam.Role.from_role_arn(self, id="role-dev02a",
                                   role_arn="arn:aws:iam::<account-dev02>:role/cdk-XXXX-cfn-exec-role-<account-dev02>-us-west-2")
                                   )))

Is this an expected behavior?

Environment

• CDK CLI Version: 1.60.0 (build 8e3f53a)
• Module Version: 1.60.0
• Node.js Version: v12.18.2
• OS: CentOS Linux release 7.8.2003 (Core)
• Language (Version): Python 3.7.9

Other information

[kichik]

The workaround we ended up using is:

def _run_next_action_in_parallel(stage: Stage):
    current_run_order = stage.next_sequential_run_order(0)  # passing 0 means it doesn't advance the run oder
    stage.next_sequential_run_order(1 - current_run_order)  # send the order back to 1 so the next stage runs in parallel

 
stage.add_application(EpsRoute53(self, f"dev01-route53", env=environments["dev01"], account_identifier="dev01"))
_run_next_action_in_parallel(stage)
stage.add_application(EpsRoute53(self, f"dev02-route53", env=environments["dev02"], account_identifier="dev02"))
_run_next_action_in_parallel(stage)

It resets the run order after each application and allows them to run in parallel.

[karthikns16]

@rix0rrr , Thank you for reviewing my request. Any tentative of ETA on when we could get this feature added?

Even with run order say if I had two accounts, the action in runOrder 1 has to be successful for both the accounts for action in subsequent order to start. Instead of stopping the whole pipeline when a deployments fails in one of the many accounts, shouldn’t it stop just the deployment just in that one account and push forward in the remaining accounts.