dynamodb-users

Overview

Provisions the DynamoDB table that serves as the invitation-only allowlist for Cognito user registration. The Cognito pre-signup Lambda checks this table to block self-registration by unapproved users.

CloudFormation Stack

firefly-dynamodb-users

Dependencies

Deploy

None — this workflow has no prerequisites.

Delete

• delete-func-cognito-pre-signup — pre-signup Lambda must be deleted first
• delete-func-api-users-post — users POST Lambda must be deleted first
• delete-func-api-users-delete — users DELETE Lambda must be deleted first

Required By

Deploy

• func-cognito-pre-signup — reads the allowlist to approve or reject sign-ups
• func-api-users-post — writes new allowlist entries
• func-api-users-delete — removes allowlist entries

Delete

None.

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Deploy Workflow

Description

Builds the SAM template and deploys the firefly-dynamodb-users CloudFormation stack. The table holds the set of email addresses permitted to register via Cognito.

Steps

1. Checkout repository
2. Configure AWS credentials
3. Install SAM CLI
4. sam build — template: templates/dynamodb-users.yaml
5. sam deploy — stack: firefly-dynamodb-users; no parameters (table name is hardcoded in the template)

Sequence Diagram

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Delete Workflow

Description

Deletes the firefly-dynamodb-users CloudFormation stack. All dependent Lambda functions must be removed first so they no longer reference the table.

Steps

1. Configure AWS credentials
2. Install SAM CLI
3. sam delete --stack-name firefly-dynamodb-users --no-prompts --region

Sequence Diagram

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Failure Scenarios

Scenario	Cause	Resolution
Stack in bad state with existing table data	DynamoDB by default will not delete a non-empty table during rollback	Manually empty or delete the table, then re-run
Deletion protection enabled	Stack deletion fails	Disable deletion protection in the console, then re-run
PITR delay	Some configurations block immediate deletion when PITR is active	Disable PITR on the table before deleting the stack