@ciderjs/city-gas

🌐 Overview

city-gas is a type-safe router for React and Vue 3 applications that works both in Google Apps Script (GAS) and browser environments. It features file-based routing, a flexible params DSL, and a Vite plugin that auto-generates TypeScript types for safe navigation.

📦 Installation

npm install @ciderjs/city-gas
# or
pnpm add @ciderjs/city-gas

🔥 Core Features

city-gas provides a set of framework-agnostic core features.

1. File-Based Routing

Your src/pages directory structure is automatically converted into route definitions.

• src/pages/index.tsx → /
• src/pages/about.vue → /about
• src/pages/users/show.tsx → /users/show
• src/pages/users/[id].tsx → /users/[id] (Dynamic Route)

2. Nested Routes (Layouts)

Certain filenames are reserved to function as layout components.

• _root.tsx / _root.vue: The root layout that wraps the entire application.
• _layout.tsx / _layout.vue: Provides a common layout for child routes in the same directory and its subdirectories.
• _404.tsx / _404.vue: A fallback page displayed when no matching route is found.

Project Structure Example

src/
└── pages/
    ├── _root.tsx         # The root layout wrapping the entire app
    ├── _layout.tsx       # Layout for the root and its children
    ├── _404.tsx          # Not found page
    ├── index.tsx         # Home page (route: /)
    └── users/
        ├── _layout.tsx   # Nested layout for /users/* routes only
        ├── [id].tsx      # User detail page (route: /users/[id])
        └── index.tsx     # User top page (route: /users)

3. Dynamic Routes

You can define dynamic routes by wrapping the filename in brackets, like [id].tsx. The parameter name inside the brackets (e.g., id) will be available in useParams.

• src/pages/users/[id].tsx matches /users/123, /users/abc, etc.
• src/pages/posts/[slug].vue matches /posts/my-first-post.

3. Type-Safe Parameters (DSL)

In each page, you can define the types of parameters it accepts by exporting a params constant.

• Supported types: string, number, boolean, enum, array, object
• Use ? to make a type optional (e.g., string?)

The Vite plugin detects this and generates type-safe navigate functions and useParams hooks/composables.

Example of Defining Parameters

// src/pages/users/[id].tsx
export const params = {
  // id: 'string', // path parameter is auto defined as required string
  tab: { type: 'enum', values: ['profile', 'settings'], optional: true }, // optional
};

4. Type Generation with Vite Plugin

Simply add the plugin to your vite.config.ts to watch the src/pages directory and auto-generate route and type definitions.

• .generated/router.d.ts: RouteNames and RouteParams type definitions.
• .generated/routes.ts: A map of route names to their components.

[!NOTE] The plugin uses an internal cache based on file modification times (mtime) to optimize performance and avoid unnecessary regenerations.

// vite.config.ts
import { defineConfig } from "vite";
import react from "@vitejs/plugin-react"; // or vue()
import { cityGasRouter } from "@ciderjs/city-gas/plugin";

export default defineConfig({
  plugins: [
    react(), // or vue()
    cityGasRouter(),
  ],
});

🚀 Usage with React

1. Initialization

Set up the router in your entry point (main.tsx) and wrap your application with the RouterProvider.

// src/main.tsx
import React from 'react';
import ReactDOM from 'react-dom/client';
import { createRouter } from '@ciderjs/city-gas';
import { RouterProvider } from '@ciderjs/city-gas/react';
import { pages, specialPages, dynamicRoutes } from './generated/routes';

// Create the router instance
const router = createRouter(pages, { specialPages, dynamicRoutes });

ReactDOM.createRoot(document.getElementById('root')!).render(
  <React.StrictMode>
    <RouterProvider router={router} />
  </React.StrictMode>,
);

2. Hooks

city-gas provides custom hooks for type-safe operations.

useParams

Safely access the parameters of the current page.

// src/pages/users/[id].tsx
import { useParams } from '@ciderjs/city-gas/react';

export const params = {
  tab: { type: 'enum', values: ['profile', 'settings'], optional: true },
};

export default function UserDetail() {
  // Pass the route name as an argument for strict type inference
  const { id, tab } = useParams('/users/[id]');
  
  return (
    <div>
      <h2>User: {id}</h2>
      <p>Tab: {tab ?? 'profile'}</p>
    </div>
  );
}

useNavigate

Perform page transitions with type-checking.

// src/components/SomeComponent.tsx
import { useNavigate } from '@ciderjs/city-gas/react';

const MyComponent = () => {
  const navigate = useNavigate();
  return (
    <nav>
      <button onClick={() => navigate('/')}>Home</button>
      {/* Parameters are also type-safe */}
      <button onClick={() => navigate('/users/[id]', { id: '123', tab: 'settings' })}>
        User 123
      </button>
    </nav>
  );
};

🚀 Usage with Vue

1. Initialization

Set up the router plugin in your entry point (main.ts) and mount the RouterOutlet.

// src/main.ts
import { createRouter } from '@ciderjs/city-gas';
import { createRouterPlugin, RouterOutlet } from '@ciderjs/city-gas/vue';
import { createApp } from 'vue';
import { pages, specialPages, dynamicRoutes } from './generated/routes';

const router = createRouter(pages, { specialPages, dynamicRoutes });
createApp(RouterOutlet).use(createRouterPlugin(router)).mount('#root');

2. Composables

Provides Composables for use with Vue 3's Composition API.

useParams

Safely access the parameters of the current page.

<!-- src/pages/users/[id].vue -->
<template>
  <div>
    <h2>User: {{ id }}</h2>
    <p>Tab: {{ tab ?? 'profile' }}</p>
  </div>
</template>

<script setup lang="ts">
import { useParams } from '@ciderjs/city-gas/vue';

// Pass the route name as an argument for strict type inference
const { id, tab } = useParams('/users/[id]');
</script>

<!-- Use a separate script block to export params -->
<script lang="ts">
export const params = {
  tab: { type: 'enum', values: ['profile', 'settings'], optional: true },
};
</script>

useNavigate

Perform page transitions with type-checking.

<!-- src/components/SomeComponent.vue -->
<template>
  <nav>
    <button @click="() => navigate('/')">Home</button>
    <!-- Parameters are also type-safe -->
    <button @click="() => navigate('/users/[id]', { id: '123', tab: 'settings' })">
      User 123
    </button>
  </nav>
</template>

<script setup lang="ts">
import { useNavigate } from '@ciderjs/city-gas/vue';
const navigate = useNavigate();
</script>
</script>

📜 License

MIT