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serverless-cognito-add-custom-attributes

This plugin allows you to add custom attributes to an existing CloudFormation-managed Cognito User Pool from serverless without losing all your users. At the time of writing (June 2018) CloudFormation doesn't know how to add custom attributes to a user pool without dropping and re-creating it, thus losing all your users.

This plugin also adds the specified attributes to a User Pool Client, giving that client read and write permissions for the new attribute.

Requirements

• Node 8+
• serverless 1+

Usage

Install npm i serverless-cognito-add-custom-attributes, then add serverless-cognito-add-custom-attributes to your serverless.yml plugins list.

plugins:
    - serverless-cognito-add-custom-attributes

custom:
  CognitoAddCustomAttributes: 
    CognitoUserPoolIdOutputKey: "CognitoUserPoolApplicationUserPoolId"              # The key of the outputted UserPool Ref 
    CognitoUserPoolClientIdOutputKey: "CognitoUserPoolApplicationUserPoolClientId"  # The key of the outputted UserPoolClient Ref
    CustomAttributes: 
      - 
        AttributeDataType: String
        DeveloperOnlyAttribute: False
        Mutable: True
        Name: "another" # this will end up being custom:another
        Required: False

# Only add this if not already outputting the Cognito User Pool and Client IDs, otherwise, refer to the existing outputs in the custom:CognitoAddCustomAttributes section
resources:
  Outputs:
    CognitoUserPoolApplicationUserPoolId:
      Value:
        Ref: CognitoUserPoolApplicationUserPool
    CognitoUserPoolApplicationUserPoolClientId:
      Value:
        Ref: CognitoUserPoolApplicationUserPoolClient

Details

1. Output your UserPoolId via resources.Outputs
2. Output your UserPoolClientId via resources.Outputs
3. Add CognitoAddCustomAttributes to custom with the following structure:

  CognitoUserPoolIdOutputKey: "UserPool Output Key as a String"
  CognitoUserPoolClientIdOutputKey: "UserPoolClient Output Key as a String"
  CustomAttributes:
    -
        AttributeDataType: String
        DeveloperOnlyAttribute: False
        Mutable: True
        Name: "another"
        Required: False

Note: If you have multiple userPool-userPoolClients you can specify them as an array as well

Example:

plugins:
    - serverless-cognito-add-custom-attributes

custom:
  CognitoAddCustomAttributes:
    -
      CognitoUserPoolIdOutputKey: "CognitoUserPoolApplicationUserPoolId"
      CognitoUserPoolClientIdOutputKey: "CognitoUserPoolApplicationUserPoolClientId"
      CustomAttributes:
        -
          AttributeDataType: String
          DeveloperOnlyAttribute: False
          Mutable: True
          Name: "another" # this will end up being custom:another
          Required: False
    -
      CognitoUserPoolIdOutputKey: "CognitoUserPoolApplicationUserPoolId"
      CognitoUserPoolClientIdOutputKey: "CognitoUserPoolApplicationUserPoolClientId2"
      CustomAttributes:
        -
          AttributeDataType: String
          DeveloperOnlyAttribute: False
          Mutable: True
          Name: "another" # this will end up being custom:another
          Required: False

resources:
  Outputs:
    CognitoUserPoolApplicationUserPoolId:
      Value:
        Ref: CognitoUserPoolApplicationUserPool
    CognitoUserPoolApplicationUserPoolClientId:
      Value:
        Ref: CognitoUserPoolApplicationUserPoolClient
    CognitoUserPoolApplicationUserPoolClientId2:
      Value:
        Ref: CognitoUserPoolApplicationUserPoolClient2

The names of your attributes supplied here will appear as custom:{name} when deployed.

For more information on the schema of attributes see: https://docs.aws.amazon.com/cognito-user-identity-pools/latest/APIReference/API_SchemaAttributeType.html