README.md

Leptos Image

Crafted with inspiration from Next.js

Images make a substantial impact on the size and performance of a website, so why not get them right?

Enter Leptos <Image/>, a component that enhances the standard HTML <img> element with automatic image optimization features.

Features

• Size Optimization: Automatically resizes images and converts them to the modern .webp format for an optimal balance of size and quality.
• Low-Quality Image Placeholders (LQIP): Embeds SVG placeholders extracted from original images into server-side rendered HTML, improving perceived performance during image loading.
• Faster Page Load: Prioritizes critical images, impacting Largest Contentful Paint (LCP), with the priority prop by adding a preload <link> to the document head, accelerating load times.

Version compatibility for Leptos and Leptos Image

The table below shows the compatible versions of leptos_image for each leptos version. Ensure you are using compatible versions to avoid potential issues.

leptos version	leptos_image version
0.6.*	0.2.*

Installation

To add leptos_image to your project, use cargo:

cargo add leptos_image --optional

Enable the SSR feature in your Cargo.toml:

[features]
ssr = [
    "leptos_image/ssr",
    # other dependencies...
]

hydrate = [
    "leptos_image/hydrate", 
    # other dependencies...
]

Quick Start

This requires SSR + Leptos Axum integration

1. Provide Image Context: Initialize your Leptos application with leptos_image::provide_image_context to grant it read access to the image cache.

   use leptos::*;
   
   #[component]
   fn App() -> impl IntoView {
       leptos_image::provide_image_context();
       // Your app content here
   }

2. Axum State Configuration: Incorporate ImageOptimizer into your app's Axum state.

   // Composite App State with the optimizer and leptos options.
   #[derive(Clone, axum::extract::FromRef)]
   struct AppState {
       leptos_options: leptos::LeptosOptions,
       optimizer: leptos_image::ImageOptimizer,
   }

3. Integrate with Router: Ensure your ImageOptimizer is available during SSR of your Leptos App.

   • Add Image Cache Route: Use image_cache_route to serve cached images.
   • Add ImageOptimizer to your App state.
   • Add ImageOptimizer to Leptos Context: Provide the optimizer to Leptos context using leptos_routes_with_context.

   use leptos::*;
   use leptos_axum::*;
   use leptos_image::*;
   
   async fn main() {
       // Get Leptos options from configuration.
       let conf = get_configuration(None).await.unwrap();
       let leptos_options = conf.leptos_options;
       let root = leptos_options.site_root.clone();
   
       // Create App State with ImageOptimizer.
       let state = AppState {
           leptos_options,
           optimizer: ImageOptimizer::new("/__cache/image", root, 1),
       };
   
       // Create your router
       let app = Router::new()
           .route("/api/*fn_name", post(handle_server_fns))
            // Add a handler for serving the cached images.
           .image_cache_route(&state)
           // Provide the optimizer to leptos context.
           .leptos_routes_with_context(&state, routes, state.optimizer.provide_context(), App)
           .fallback(fallback_handler)
           // Provide the state to the app.
           .with_state(state);
   }

A full working example is available in the examples directory.

Now you can use the Image Component anywhere in your app!

#[component]
pub fn MyImage() -> impl IntoView {
    view! {
        <Image
            src="/cute_ferris.png"
            blur=true
            width=750
            height=500
            quality=85
        />
    }
}

This setup ensures your Leptos application is fully equipped to deliver optimized images, enhancing the performance and user experience of your web projects.