http_interop

A lightweight package for interoperability between HTTP client and server implementations in Dart. It defines Request and Response classes and a shared client/server Handler type: Future<Response> Function(Request request).

Motivation

HTTP APIs are a common way for clients and servers to communicate. The pub.dev API is one example.

Building an API client on a specific HTTP implementation can tightly couple your library to that implementation. This can make unit tests depend on complex mocks or require end-to-end tests, limiting coverage and making tests harder to maintain.

Solution

Implement a Handler function to separate your API logic from the underlying HTTP implementation. Request and Response are simple Dart classes that you can construct and inspect directly in tests.

Pros

• Decouples application logic from the underlying HTTP implementation.
• Simplifies tests for both clients and servers.
• Allows tests to run without an HTTP stack.
• Lets users choose or switch HTTP implementations.

Cons

• Provides limited support for streaming APIs, long polling, and WebSockets.
• Adds a dependency to your library.
• Requires consumers to depend on both the interop package and an adapter package.

Existing implementations

• http_interop_http: an adapter for package:http.
• http_interop_io: adapters for dart:io clients and servers.
• http_interop_dio: an adapter for Dio.

Projects using http_interop

• json_api: a JSON:API client and server library.