sapper-firebase

The default Sapper template with firebase hosting support, available for Rollup and webpack.

Getting started

Using degit

degit is a scaffolding tool that lets you create a directory from a branch in a repository. Use either the rollup or webpack branch in sapper-template:

# for Rollup
npx degit "Olyno/sapper-firebase#rollup" my-app
# for webpack
npx degit "Olyno/sapper-firebase#webpack" my-app

Using GitHub templates

Alternatively, you can use GitHub's template feature with the sapper-template-rollup or sapper-template-webpack repositories.

Running the project

However you get the code, you can install dependencies and run the project in development mode with:

cd my-app
npm install # or yarn
npm run dev

Open up localhost:3000 and start clicking around.

Consult sapper.svelte.dev for help getting started.

To run your project as firebase project, here is the list of commands to do:

cd my-app
npm install # or yarn
cd functions
npm install
cd ..
npm start

Open up localhost:5000 and start clicking around.

Structure

Sapper expects to find two directories in the root of your project — src and static.

src

The src directory contains the entry points for your app — client.js, server.js and (optionally) a service-worker.js — along with a template.html file and a routes directory.

src/routes

This is the heart of your Sapper app. There are two kinds of routes — pages, and server routes.

Pages are Svelte components written in .svelte files. When a user first visits the application, they will be served a server-rendered version of the route in question, plus some JavaScript that 'hydrates' the page and initialises a client-side router. From that point forward, navigating to other pages is handled entirely on the client for a fast, app-like feel. (Sapper will preload and cache the code for these subsequent pages, so that navigation is instantaneous.)

Server routes are modules written in .js files, that export functions corresponding to HTTP methods. Each function receives Express request and response objects as arguments, plus a next function. This is useful for creating a JSON API, for example.

There are three simple rules for naming the files that define your routes:

• A file called src/routes/about.svelte corresponds to the /about route. A file called src/routes/blog/[slug].svelte corresponds to the /blog/:slug route, in which case params.slug is available to the route
• The file src/routes/index.svelte (or src/routes/index.js) corresponds to the root of your app. src/routes/about/index.svelte is treated the same as src/routes/about.svelte.
• Files and directories with a leading underscore do not create routes. This allows you to colocate helper modules and components with the routes that depend on them — for example you could have a file called src/routes/_helpers/datetime.js and it would not create a /_helpers/datetime route

static

The static directory contains any static assets that should be available. These are served using sirv.

In your service-worker.js file, you can import these as files from the generated manifest...

import { files } from '@sapper/service-worker';

...so that you can cache them (though you can choose not to, for example if you don't want to cache very large files).

Bundler config

Sapper uses Rollup or webpack to provide code-splitting and dynamic imports, as well as compiling your Svelte components. With webpack, it also provides hot module reloading. As long as you don't do anything daft, you can edit the configuration files to add whatever plugins you'd like.

Deployment

To deploy a version of your app, run npm run deploy.

Using external components

When using Svelte components installed from npm, such as @sveltejs/svelte-virtual-list, Svelte needs the original component source (rather than any precompiled JavaScript that ships with the component). This allows the component to be rendered server-side, and also keeps your client-side app smaller.

Because of that, it's essential that the bundler doesn't treat the package as an external dependency. You can either modify the external option under server in rollup.config.js or the externals option in webpack.config.js, or simply install the package to devDependencies rather than dependencies, which will cause it to get bundled (and therefore compiled) with your app:

npm install -D @sveltejs/svelte-virtual-list

Firebase support

To support firebase hosting, you must change the name from your-project-name to the name of your firebase project in the .firebaserc file. After that, go into functions directory, and in the package.json file, edit node version to your node version (e.g node 13.4.3 should be 13).

You can try the firebase version using npm start (or yarn start).

Bugs and feedback

Sapper is in early development, and may have the odd rough edge here and there. Please be vocal over on the Sapper issue tracker.