Tell us about API design and interaction contracts: approaches, standards, protocols, schema stores.

Designing APIs and interaction contracts involves several key aspects:

• Approaches:

  • REST — an architectural style using HTTP methods and resources.
  • RPC (Remote Procedure Call) — calling remote procedures.
  • GraphQL — queries with descriptions of the required data.

• Standards and protocols:

  • HTTP/HTTPS — the basic protocol for web APIs.
  • OpenAPI (Swagger) — a standard for describing REST APIs, allowing for documentation and client code generation.
  • gRPC — a protocol based on HTTP/2 using protobuf for serialization.

• Schema repositories:

  • Code repositories (Git) for storing API descriptions.
  • Specialized services, such as SwaggerHub, Stoplight, which allow storing, versioning, and documenting APIs.

An interaction contract is a formal description of an API that defines which requests and responses are supported, their structure, and usage rules. It helps development and integration teams work coherently and reduces the risk of errors.