GPUI Router

A declarative routing library for GPUI with support for nested routes, transitions, guards, and middleware.

Features

• 🎯 Declarative Route Definition - Define routes with a fluent builder API
• 🎨 Route Transitions - Built-in fade, slide, and scale animations
• 🔀 Nested Routing - Support for parent/child route hierarchies with RouterOutlet
• 🛡️ Route Guards - Authentication, authorization, and custom guards
• 🔌 Middleware - Before/after hooks for navigation events
• 📝 Named Routes - Navigate using route names instead of paths
• 🔍 Route Matching - Pattern matching with parameters and constraints
• 📊 Performance - Route cache for optimized lookups
• ⚡ Error Handling - Custom 404 and error handlers

Installation

Add to your Cargo.toml:

[dependencies]

gpui_router = "0.1"

gpui = "0.2"

Quick Start

use gpui::*;
use gpui_router::*;

fn main() {
    Application::new().run(|cx| {
        // Initialize router with routes
        init_router(cx, |router| {
            router.add_route(
                Route::new("/", home_page)
                    .transition(Transition::fade(300))
            );
            
            router.add_route(
                Route::new("/about", about_page)
                    .transition(Transition::slide_left(400))
            );
        });

        // Open window
        cx.open_window(WindowOptions::default(), |_, cx| {
            cx.new(|_| AppView)
        })
    });
}

fn home_page(_cx: &mut App, _params: &RouteParams) -> AnyElement {
    div().child("Home Page").into_any_element()
}

fn about_page(_cx: &mut App, _params: &RouteParams) -> AnyElement {
    div().child("About Page").into_any_element()
}

struct AppView;

impl Render for AppView {
    fn render(&mut self, _window: &mut Window, _cx: &mut Context<Self>) -> impl IntoElement {
        div()
            .flex()
            .flex_col()
            .size_full()
            .child(RouterOutlet::new())
    }
}

Navigation

The library provides a Flutter-style navigation API:

use gpui_router::Navigator;

// Push new route
Navigator::push(cx, "/profile");

// Replace current route
Navigator::replace(cx, "/login");

// Go back
Navigator::pop(cx);

// Go forward
Navigator::forward(cx);

// Get current path
let path = Navigator::current_path(cx);

// Check navigation state
if Navigator::can_pop(cx) {
    Navigator::pop(cx);
}

Flutter-style API

// Navigator.of(context) style
Navigator::of(cx).push("/users").pop();

// Or direct static methods
Navigator::push(cx, "/users/123");

Route Transitions

The router supports smooth transitions between routes:

use gpui_router::*;

// Fade transition
Route::new("/fade", page).transition(Transition::fade(300))

// Slide transitions
Route::new("/left", page).transition(Transition::slide_left(400))
Route::new("/right", page).transition(Transition::slide_right(400))
Route::new("/up", page).transition(Transition::slide_up(400))
Route::new("/down", page).transition(Transition::slide_down(400))

// Scale transitions
Route::new("/zoom-in", page).transition(Transition::zoom_in(350))
Route::new("/zoom-out", page).transition(Transition::zoom_out(350))
Route::new("/custom", page).transition(Transition::scale(0.8, 1.2, 400))

// No transition
Route::new("/instant", page).transition(Transition::None)

Nested Routes

Create hierarchical route structures with RouterOutlet:

use gpui_router::*;

fn dashboard_layout(_cx: &mut App, _params: &RouteParams) -> AnyElement {
    div()
        .flex()
        .child("Dashboard Header")
        .child(RouterOutlet::new())  // Child routes render here
        .into_any_element()
}

// Configure nested routes
init_router(cx, |router| {
    router.add_route(
        Route::new("/dashboard", dashboard_layout)
            .children(vec![
                Route::new("overview", overview_page),
                Route::new("settings", settings_page),
                Route::new("analytics", analytics_page),
            ])
    );
});

Route Parameters

Extract parameters from route paths:

use gpui_router::*;

// Define route with parameter
Route::new("/users/:id", user_profile)

// Access parameters in handler
fn user_profile(_cx: &mut App, params: &RouteParams) -> AnyElement {
    let user_id = params.get("id").unwrap_or(&"unknown".to_string());
    div()
        .child(format!("User Profile: {}", user_id))
        .into_any_element()
}

// Navigate with parameters
Navigator::push(cx, "/users/123");

// Type-safe parameter extraction
let id: Option<u32> = params.get_as("id");

Route Guards

Protect routes with authentication and authorization:

use gpui_router::*;

// Authentication guard with custom check function
fn is_authenticated(cx: &App) -> bool {
    cx.try_global::<AuthState>()
        .map(|state| state.is_logged_in())
        .unwrap_or(false)
}

Route::new("/profile", profile_page)
    .guard(AuthGuard::new(is_authenticated, "/login"))

// Role-based guard
fn get_user_role(cx: &App) -> Option<String> {
    cx.try_global::<CurrentUser>()
        .map(|user| user.role.clone())
}

Route::new("/admin", admin_page)
    .guard(RoleGuard::new(get_user_role, "admin", Some("/forbidden")))

// Permission-based guard
fn has_permission(cx: &App, permission: &str) -> bool {
    cx.try_global::<UserPermissions>()
        .map(|perms| perms.contains(permission))
        .unwrap_or(false)
}

Route::new("/users/:id/delete", delete_user)
    .guard(PermissionGuard::new(has_permission, "users.delete"))

// Custom guard with closure
Route::new("/premium", premium_page)
    .guard(guard_fn(|cx, _request| async move {
        if is_premium_user(cx) {
            GuardResult::allow()
        } else {
            GuardResult::redirect("/upgrade")
        }
    }))

Middleware

Add before/after hooks to routes:

use gpui_router::*;

// Create middleware from functions
struct LoggingMiddleware;

impl RouteMiddleware for LoggingMiddleware {
    type Future = Pin<Box<dyn Future<Output = ()> + Send>>;

    fn before_navigation(&self, _cx: &App, request: &NavigationRequest) -> Self::Future {
        log::info!("Navigating to: {}", request.to);
        Box::pin(async {})
    }

    fn after_navigation(&self, _cx: &App, request: &NavigationRequest) -> Self::Future {
        log::info!("Navigated to: {}", request.to);
        Box::pin(async {})
    }
}

Route::new("/", home_page)
    .middleware(LoggingMiddleware)

Named Routes

Navigate using route names:

use gpui_router::*;

// Define named route
Route::new("/profile/:id", profile_page)
    .name("user-profile")

// Navigate by name
let mut params = RouteParams::new();
params.set("id".to_string(), "123".to_string());
Navigator::push_named(cx, "user-profile", &params);

// Generate URL from name
if let Some(url) = Navigator::url_for(cx, "user-profile", &params) {
    // url = "/profile/123"
}

Error Handling

Custom error and 404 handlers:

use gpui_router::*;

init_router(cx, |router| {
    router
        .error_handlers(ErrorHandlers::new()
            .on_not_found(|path, _cx| {
                div().child(format!("404: {} not found", path)).into_any_element()
            })
            .on_error(|error, _cx| {
                div().child(format!("Error: {}", error)).into_any_element()
            })
        );
});

Examples

Run the transition demo:

cargo run --example transition_demo

Architecture

Module Structure

Route Matching

Routes are matched using patterns with support for:

• Static segments: /about
• Dynamic parameters: /users/:id
• Wildcards: /docs/*path
• Constraints: /users/:id<\d+> (numeric only)

Performance

• Route cache for O(1) lookups after first match
• Efficient parent route resolution
• Minimal allocations during navigation
• Cache statistics for monitoring

Minimum Supported Rust Version (MSRV)

This crate requires Rust 1.75 or later.

License

Licensed under either of:

• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

1. Fork the repository
2. Create your feature branch (git checkout -b feature/amazing-feature)
3. Commit your changes (git commit -m 'Add some amazing feature')
4. Push to the branch (git push origin feature/amazing-feature)
5. Open a Pull Request

Acknowledgments

• Inspired by Flutter Navigator
• Built for GPUI by Zed Industries