cap-nodejs

ADR 0002: Use Symbol-Based NestJS DI Tokens

Status

Accepted

Context

CAP adapters are independent packages. The core package should not import concrete storage or transport classes, and adapter registration should avoid string-token collisions.

Decision

CAP exposes Symbol-based NestJS dependency injection tokens for storage and transport:

PUBLISH_STORAGE
RECEIVED_STORAGE
PUBLISHER
SUBSCRIBER

Adapters bind these tokens with Nest providers.

Consequences

The core package depends only on interfaces and tokens.
Adapters can be implemented and released independently.
Applications can swap storage or transport implementations.
Documentation and examples must consistently use the exported tokens.