V2 Pre-Token Generation Lamba / Cognito Support about serverless

[btamadio]

I'd also like to use this feature.

Unfortunately, it seems the line you've posted here doesn't control the allowed versions for PreTokenGeneration events, as it only gets evaluated when the trigger is one of "CustomEmailSender" or "CustomSMSSender"

See:

serverless/lib/plugins/aws/package/compile/events/cognito-user-pool.js

Line 189 in 7b1e012

if (customSenderSources.includes(trigger)) {

When I simply try to set the lambdaVersion in my event configuration for the PreTokenGeneration trigger, I get this error:

Warning: Invalid configuration encountered
  at 'functions.MyFunction.events.1.cognitoUserPool': unrecognized property 'lambdaVersion'

[jrdnull]

I was able to do this by specifying the LambdaConfig in the UserPool resource, e.g

    UserPool:
      Type: AWS::Cognito::UserPool
      Properties:
        UserPoolAddOns:
          AdvancedSecurityMode: "AUDIT"
        LambdaConfig:
          PreTokenGenerationConfig:
            LambdaArn: arn:aws:lambda:${aws:region}:${aws:accountId}:function:{$self:service}-${self:provider.stage}-preTokenGeneration
            LambdaVersion: V2_0
        ...

Also specify permission else it won't be able to invoke it

    PreTokenGenerationLambdaInvokePermission:
      Type: "AWS::Lambda::Permission"
      Properties:
        FunctionName: arn:aws:lambda:${aws:region}:${aws:accountId}:function:{$self:service}-${self:provider.stage}-preTokenGeneration
        Action: "lambda:InvokeFunction"
        Principal: "cognito-idp.amazonaws.com"