# Path Handler

A common use-case for HTTP servers is to serve different content depending on the URL that the user requested. Handy-Httpd accomplishes this with its PathHandler that can match HTTP methods (GET, POST, etc.) and URLs to specific handlers.

A PathHandler is an implementation of HttpRequestHandler that will delegate incoming requests to other handlers based on the request's HTTP method and URL. Handlers are registered with the PathHandler via one of the overloaded addMapping methods.

For example, suppose we have a handler named userHandler that we want to invoke on GET requests to URLs like /users/:userId:ulong.

auto pathHandler = new PathHandler()
    .addMapping(Method.GET, "/users/:userId:ulong", userHandler);
new HttpServer(pathHandler).start();

# Path Patterns

In our example, we used the pattern /users/:userId:ulong. This pattern matches URLs like /users/<any valid ulong>. Under the hood, the PathHandler is using the path-matcher (opens new window) library to do matches.

For a complete explanation of how path matching works, check out the path-matcher's README and source code, but we'll include some examples here for completeness' sake.

  • /data matches the URL /data literally, as-is.
  • /data/* matches the URL /data/a, or /data/1, or any other single segment under /data, but not something like /data/a/b/c.
  • /users/:id:ulong matches /users/12345, but not /users/andrew.
  • /** matches any URL.