Get ARN from step machine

Serverless Framework
,
1

Hi guys,

Been fighting with the following for quite a bit and googling doesn’t help much…

I’ve been following a combination of:

https://serverless.com/plugins/serverless-step-functions/#current-gotcha and https://serverless.com/plugins/serverless-step-functions/#how-to-specify-the-statemachine-arn-to-environment-variables

Problem is if I follow the code as it is, first it complains about:

  Trying to populate non string value into a string for variable ${opt:stage}. Please make sure the value of the property is a string.

So apparently the following somehow is not valid:

resources:
  Outputs:
    halfHourMachine:
      Value:
        Ref: HalfHourMachineDash${self:service}Dash${opt:stage}

So I am like, ok whatever, let’s go with ${self:provider.stage} instead

resources:
  Outputs:
    halfHourMachine:
      Value:
        Ref: HalfHourMachineDash${self:service}Dash${self:provider.stage}

But then I got the following error:

  Error: The CloudFormation template is invalid: Template format error: Unresolved resource dependencies [HalfHourMachineDashms-pipedriveDashdev] in the Resources block of the template

For completeness here’s the relevant parts:

Step Function

stepFunctions:
  stateMachines:
    halfHourMachine:
      name: halfHourMachine-${self:service}-${self:provider.stage}
      definition:
        StartAt: WaitSecondsTask
        States:
          WaitSecondsTask:
            Type: Wait
            SecondsPath: $.wait
            Next: checkDealsAndUpdateIfOlderThan30MinutesTask
          checkDealsAndUpdateIfOlderThan30MinutesTask:
            Type: Task
            Resource:
              Fn::GetAtt: [checkDealsAndUpdateIfOlderThan30Minutes, Arn]
            End: true

Environemnt

  environment:
    stage: ${self:provider.stage}
    stepmachine_arn: ${self:resources.Outputs.halfHourMachine.Value}

Function to be called

functions:
  checkDealsAndUpdateIfOlderThan30Minutes:
    handler: index.checkDealsAndUpdateIfOlderThan30Minutes

Any help would be greatly appreciated!

1 Like
2

To anyone having a similar problem I solved it with the following:

Step Functions:

stepFunctions:
  stateMachines:
    checkDealAndUpdateIfOlderThan30MinutesMachine:
      name: checkDealAndUpdateIfOlderThan30MinutesMachine
      definition:
        StartAt: WaitSecondsTask
        States:
          WaitSecondsTask:
            Type: Wait
            SecondsPath: $.wait
            Next: checkDealsAndUpdateIfOlderThan30MinutesTask
          checkDealsAndUpdateIfOlderThan30MinutesTask:
            Type: Task
            Resource: 'arn:aws:lambda:#{AWS::Region}:#{AWS::AccountId}:function:${self:service}-${opt:stage}-checkDealsAndUpdateIfOlderThan30Minutes'
            End: true

Environment:

  environment:
    stage: ${self:provider.stage}
    stepmachine_arn: ${self:resources.Outputs.CheckDealAndUpdateIfOlderThan30MinutesMachine.Value}

and Resources:

resources:
  Outputs:
    CheckDealAndUpdateIfOlderThan30MinutesMachine:
      Value:
        Ref: CheckDealAndUpdateIfOlderThan30MinutesMachine

Everything works, but I am now having another problem which is created by the fact that when I deploy to dev/prod one of them works the other one doesn’t as it claims the stepMachine is already created…

3

Can you add the stage in the stage machine name?

4

Good point, just tried and it doesn’t work?

It could be thought.

That’s what I tried:

org: melmacaluso
app: ms-pipedrive
service: ms-pipedrive

frameworkVersion: '>=1.0.0 <2.0.0'

provider:
  name: aws
  runtime: nodejs12.x
  region: eu-west-2
  stage: ${opt:stage, 'dev'}
  environment:
    stage: ${self:provider.stage}
    stepmachine_arn: ${self:resources.Outputs.CheckDealAndUpdateIfOlderThan30MinutesMachine.Value}
  iamRoleStatements:
    - Effect: 'Allow'
      Action:
        - states:*
        - secretsmanager:*
      Resource: '*'

functions:
  createDeal:
    handler: index.createDeal
    events:
      - http:
          path: create-deal
          method: post
          cors: trues

  checkDealsAndUpdateIfOlderThan30Minutes:
    handler: index.checkDealsAndUpdateIfOlderThan30Minutes

stepFunctions:
  stateMachines:
    checkDealAndUpdateIfOlderThan30MinutesMachine:
      name: checkDealAndUpdateIfOlderThan30MinutesMachine-${self:custom.service}-${opt:stage}
      definition:
        StartAt: WaitSecondsTask
        States:
          WaitSecondsTask:
            Type: Wait
            SecondsPath: $.wait
            Next: checkDealsAndUpdateIfOlderThan30MinutesTask
          checkDealsAndUpdateIfOlderThan30MinutesTask:
            Type: Task
            Resource: 'arn:aws:lambda:#{AWS::Region}:#{AWS::AccountId}:function:${self:service}-${opt:stage}-checkDealsAndUpdateIfOlderThan30Minutes'
            End: true

package:
  individually: true

plugins:
  - serverless-bundle
  - serverless-step-functions
  - serverless-pseudo-parameters

custom:
  bundle:
    sourcemaps: true
    linting: false

resources:
  Outputs:
    CheckDealAndUpdateIfOlderThan30MinutesMachine:
      Value:
        Ref: CheckDealAndUpdateIfOlderThan30MinutesMachine-${self:custom.service}-${opt:stage}
5

Just tried (I could be wrong) but it doesn’t work?

org: melmacaluso
app: ms-pipedrive
service: ms-pipedrive

frameworkVersion: '>=1.0.0 <2.0.0'

provider:
  name: aws
  runtime: nodejs12.x
  region: eu-west-2
  stage: ${opt:stage, 'dev'}
  environment:
    stage: ${self:provider.stage}
    stepmachine_arn: ${self:resources.Outputs.CheckDealAndUpdateIfOlderThan30MinutesMachine.Value}
  iamRoleStatements:
    - Effect: 'Allow'
      Action:
        - states:*
        - secretsmanager:*
      Resource: '*'

functions:
  createDeal:
    handler: index.createDeal
    events:
      - http:
          path: create-deal
          method: post
          cors: trues

  checkDealsAndUpdateIfOlderThan30Minutes:
    handler: index.checkDealsAndUpdateIfOlderThan30Minutes

stepFunctions:
  stateMachines:
    checkDealAndUpdateIfOlderThan30MinutesMachine:
      name: checkDealAndUpdateIfOlderThan30MinutesMachine-${self:custom.service}-${opt:stage}
      definition:
        StartAt: WaitSecondsTask
        States:
          WaitSecondsTask:
            Type: Wait
            SecondsPath: $.wait
            Next: checkDealsAndUpdateIfOlderThan30MinutesTask
          checkDealsAndUpdateIfOlderThan30MinutesTask:
            Type: Task
            Resource: 'arn:aws:lambda:#{AWS::Region}:#{AWS::AccountId}:function:${self:service}-${opt:stage}-checkDealsAndUpdateIfOlderThan30Minutes'
            End: true

package:
  individually: true

plugins:
  - serverless-bundle
  - serverless-step-functions
  - serverless-pseudo-parameters

custom:
  bundle:
    sourcemaps: true
    linting: false

resources:
  Outputs:
    CheckDealAndUpdateIfOlderThan30MinutesMachine:
      Value:
        Ref: CheckDealAndUpdateIfOlderThan30MinutesMachine-${self:custom.service}-${opt:stage}