Maintaining separation from external services
While request and response models handle data transformation at our API surface, our application must also interact with external services like email systems, file storage, and third-party APIs. The Application layer maintains separation from these services through ports— interfaces that define exactly what capabilities our application requires without specifying implementation details. In our task management system, external services might include:
- Email services for sending notifications (such as SendGrid or AWS SES)
- File storage systems for attachments (such as AWS S3 or Google Cloud Storage)
- Authentication services (such as Auth0 or Okta)
- Calendar integration services (such as Google Calendar or Microsoft Outlook)
- External messaging systems (such as Slack or Microsoft Teams)
While request/response models and ports both serve to maintain clean architectural boundaries, they address...
