spry_fsrouter 1.1.1

Define Spry router in the way of filesystem router layout, it builds on top of Spry router, supports group route mount, nested route, handler mount, middleware, etc.

Filesystem router for Spry

Define Spry router in the way of filesystem router layout, it builds on top of spry_router, supports group route mount, nested route, handler mount, middleware, etc.

Installation

Add spry_fsrouter to your pubspec.yaml file:

dev_dependencies:
  spry_fsrouter: any

Or install it from the command line:

dart pub add spry_fsrouter -d

The spry_fsrouter package is a CLI tool, so you need to add the -d option to install it as a development dependency.

The app Directory

The directory where the router is located, which is also the directory where the generated route definitions are located. is the only place you import router handler.

It is lib/app relative to where your project is located, and the app directory will contain all your middleware and handlers.

directories and files inside app

In the app directory:

1. Directories are used to define routes. A route is a single route of nested directories, following a hierarchy from the root directory to subdirectories.
2. Files are used to create middleware, handlers, etc., see Special Files.

Route Segments

Each directory is a route segment, and the name of the directory is the name of the route segment.

        app/
         ├── api/
         │   ├── users/
         │   │     │
spry.fun[/][api]/[users]
╰──────────URL─────────╯

Nested Routes

To create a nested route, you can nest folders inside each other. For example, you can add a new /api/users route by nesting two new folders in the app directory.

The /api/users route is composed of three segments:

• / Root segment
• api Segment
• users Segment

Special Files

Spry filesystem router provides a set of special files that you can use in your routes. These files are:

• handler.dart - A handler file, which needs to expose a variable or function named handler.
• middleware.dart - A middleware file, which needs to expose a variable or function named middleware.
• {name}.middleware.dart - The parameter middleware file, which needs to provide a standard Spry router parameter middleware named middleware.
• segment.yaml - Configure the current route segment.

Colocation

Under normal circumstances, all routing segments follow the directory nesting rules to generate paths, for example: lib/app/api/users will produce /api/users and mount /lib/app/api/users/handler.dart to the root router.

Sometimes we expect /api/* to be an independent collection, create an independent router and then mount it on the root router.

You can create a segment.yaml file, define a variable named colocation and set it to true:

# lib/app/api/segment.yaml
colocation: true

Creating Routes

Inside the app directory, Directories are used to define routes.

Each directory is a route segment that maps to a URL segment. to create a nested route, you can nest folders inside each other.

        app/
         ├── api/
         │   ├── users/
         │   │     │
spry.fun[/][api]/[users]
╰──────────URL─────────╯

A special handler.dart file is used to make route segments publicly accessible.

app/
  ├── all.dart    => /
  ├── api/
      ├── handler.dart => /api

Creating Middleware

A special middleware.dart file is used to create middleware.

app/
  ├── middleware.dart    => /
  ├── api/
      ├── middleware.dart => /api

// app/middleware.dart
import 'package:spry/spry.dart';

Future<void> middleware(Context context, Next next) async {
  // Before do something
  await next();
  // After do something
}

If you need to create a parameter middleware, you can create a file named {name}.middleware.dart, and the middleware function needs to be named middleware.

https://spry.fun/api/users/123
╰───URL────────╯╰──Segment──╯

app/
  ├── api/
      ├── [id].middleware.dart => /api/:id

// app/api/id.middleware.dart
import 'package:spry/spry.dart';

Future<void> middleware(Context context, Object? value, ParamNext next) async {
  final parsedValue = ... // Parse the value
  await next(parsedValue);
}

Dynamic Segments

Dynamic segments are segments that can match any URL path segment. They are defined by wrapping the segment name in square brackets ([]).

        app/
         ├── api/
         │   ├── [id]/
         │   │     │
spry.fun[/][api]/[:id]
╰──────────URL────────╯

Define a dynamic segment expression

You can define a dynamic segment expression, which is a Prexp expression that matches the segment value.

Create a segment.yaml file in the directory, and define a variable named expression:

        app/
         ├── api/
         │   ├── [id]/
         │   │     │
spry.fun[/][api]/[:id(\d+)]
╰──────────URL────────╯

# app/api/[id]/segment.yaml
expression: '(\d+)'

Now, the id segment can only match a number.

Defining HTTP verb

You can define the HTTP verb of the route by defining a (verb)/ directory.

The app/handler.dart file will be mounted to the all verb.

Define a (get)/ directory, the app/(get)/handler.dart file will be mounted to the get verb.

        app/
         ├── (get)/
         │   ├── handler.dart
         │   │
spry.fun[/]{GET}

If you don't define the HTTP verb, the default is all.

Generating root router

Before using the router, you need to run additional commands to generate the final router instance.

$ dart run spry_fsrouter

This command will generate a lib/app/app.dart file, which is the root router instance.

The lib/app/app.dart exports the root router instance, and you can use it in your application.

import 'package:spry/spry.dart';
import 'package:your_app/app/app.dart';

void main() async {
  final Spry spry = Spry();

  // Do something

  await spry.listen(app, port: 3000);
  print('Listening on http://localhost:3000');
}

API Reference

Read the API Reference for more information.