xngineers / migrate-cognito-user-pool-lambda

migrate-cognito-user-pool-lambda

See this blog post for a description

Usage

Follow these steps to use the migration Lambda function:

1. Create a new user pool client in the old user pool This client must have the OAuth flow ALLOW_ADMIN_USER_PASSWORD_AUTH enabled.

2. Configure all clients in the new user pool that are allowed to trigger user migration These clients must use the OAuth flow USER_PASSWORD_AUTH.

3. Build the lambda source code

   npm install && npm run build

4. Create in Lambda function in the AWS console in the same account as the new user pool

   • Configure the OLD_USER_POOL_REGION, OLD_USER_POOL_ID, and OLD_CLIENT_ID environment variables

   • Grant the required permissions for accessing the user pool

     If the old user pool is in the same AWS account: Allow the actions cognito-idp:AdminGetUser and cognito-idp:AdminInitiateAuth in the execution role of the lambda function

     If the old user pool is in a different AWS account:

     1. Create a role in the account that owns the user pool that Allows the cognito-idp:AdminGetUser and cognito-idp:AdminInitiateAuth actions and that trusts the execution role of the lambda function
     2. Allow the action sts:AssumeRole for the ARN of the created role in the execution role of the lambda function
     3. Configure the OLD_ROLE_ARN and OLD_EXTERNAL_ID environment variables for the lambda function

5. Configure the trigger User Migration for the new User Pool to call the migration lambda function