RE1REST

RE1REST is a design approach to RESTful APIs that emphasizes real-time, event-driven updates alongside traditional resource-oriented interactions. The term RE1REST commonly stands for Real-time Event-driven REST, and it appears in academic discussions and certain open-source projects as a pattern for delivering continuous state changes to clients while preserving familiar REST concepts.

In RE1REST, resources are identified by URIs and can be manipulated using standard HTTP methods. What differentiates it is the built-in support for streaming changes: clients can subscribe to event streams associated with a resource and receive updates as events occur. This streaming can be implemented through technologies such as Server-Sent Events or WebSocket connections. Event metadata, often conveyed through designated headers or payload fields, describes the type, sequence, and origin of each change, aiding ordering and reconstruction of resource state on the client side. While requests remain stateless and conform to REST principles, the system emphasizes a shift from single-state responses to a continuous sequence of state changes, with an emphasis on hypermedia-driven navigation and eventual consistency.

Key considerations for RE1REST include ensuring idempotent and cache-friendly operations where appropriate, managing backpressure on streams, and designing effective conflict resolution and versioning strategies. The approach is well-suited for applications requiring near real-time visibility, such as dashboards, collaborative editing, and IoT monitoring, but it adds architectural complexity compared with traditional REST APIs. Adoption is informal and varies by project, with no formal standard governing RE1REST.

See also: REST, HATEOAS, Server-Sent Events, WebSocket, event-driven architecture, API streaming.