koa-router is a router middleware for koa that provides Express-style routing with support for named parameters and routes.
The tool solves the problem of mapping HTTP requests to handler functions in koa applications. It works by matching URL patterns against incoming requests using regular expressions, derived from path specifications, and executing associated middleware or controller actions. The approach mirrors Express routing conventions, making it familiar to developers transitioning from Express to koa.
Developers should choose this tool if they are building koa applications and want routing semantics similar to Express. It suits projects of any scale that need structured request handling with named routes, URL parameter extraction, and middleware composition. The tool supports multiple routers that can be nested, allowing modular application architecture. It handles HTTP verb methods including GET, POST, PUT, PATCH, and DELETE, plus OPTIONS and error responses for unsupported methods.
The project maintains active engagement with its codebase, regularly addressing issues and pull requests to keep the tool functional with current koa versions. Development activity shows consistent responsiveness to user-reported problems and feature requests. The maintainers prioritize compatibility with koa's evolution, as evidenced by API updates to align with koa's shift to promise-based middleware.
