shelf_dynamic_forwarder 1.0.0

A utility for dynamic router composition in Dart's shelf framework, enabling clean forwarding with path segment rewriting.

shelf_dynamic_forwarder A utility package for Dart's shelf framework that simplifies dynamic route composition and forwarding.

This package solves the complex problem of using dynamic path segments (like user IDs or tenant names) as part of your router's prefix, allowing you to rewrite the URI path to isolate your child handlers. All captured path parameters are automatically forwarded as x- prefixed HTTP headers.

Features Dynamic Path Capture: Define arbitrary path parameters in your route pattern.

URI Rewriting: Correctly constructs an absolute URI with an isolated path (e.g., transforms /tenant/123/data to /data) to ensure child routers match correctly.

Parameter Forwarding: Automatically converts captured parameters (e.g.,

Handler Switching: Uses a map-based routing table to replace complex switch statements.

Installation Add shelf_dynamic_forwarder to your pubspec.yaml:

dependencies: shelf: ^1.4.0 shelf_router: ^1.1.0 shelf_dynamic_forwarder: ^1.0.0

Usage Use the createDynamicRouter function to wrap your child handlers.

1. Define Child Handlers Your child handlers define their routes relative to the path segment they expect to receive (e.g., /filenames).

import 'package:shelf_router/shelf_router.dart'; import 'package:shelf/shelf.dart';

Router get filenamesRequest { final handler = Router(); handler.get('/filenames', (Request req) { // Access forwarded parameters via headers final adminId = req.headers['x-adminId'] ?? 'N/A'; // Add Your logic code here... return Response.ok('Admin: $adminId'); }); return handler; }

Router get postMediaRequest { final handler = Router(); handler.post('/media', (Request req) { // Access forwarded parameters via headers final adminId = req.headers['x-adminId'] ?? 'N/A'; // Add Your logic code here... return Response.ok('Admin: $adminId'); }); return handler; }

2. Configure the Dynamic Router Define your top-level router using createDynamicRouter.

import 'package:shelf_dynamic_forwarder/shelf_dynamic_forwarder.dart';

// 1. Define the routes map: Path Segment -> Handler final Map<String, Handler> dynamicRoutes = { // Add other handlers here... 'filenames': filenamesRequest, 'media': postMediaRequest, };

// 2. Create the dynamic router instance Handler get router { final dynamicRouter = createDynamicRouter( // The route pattern MUST end with a capturing group for the path segment. routePattern: '/api/

// 3. Return the dynamicRouter to main return dynamicRouter; }

// 4. Use router void main() { final handler = const Pipeline() .addMiddleware(logRequests()) .addHandler(router); }

// Requesting /api/user1/42/filenames will now hit filenamesRequest()

Dynamic Parameters The parameters captured in the routePattern (