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A template for setting up a Sapper project with mdsvex using Rollup. This template is different than default sapper-mdsvex-template in that it uses dynamic module importing to combine Sapper dyanmic pages with mdsvex templates.
degit
To create a new Sapper project based on Rollup locally, run
npx degit "ryanfiller/sapper-mdsvex-starter#main" my-app
degit
is a scaffolding tool that lets you create a directory from a branch in a repository.
Replace my-app
with the path where you wish to create the project.
Alternatively, you can create the new project as a GitHub repository using GitHub's template feature.
Go to ryanfiller/sapper-mdsvex-starter and click on "Use this template" to create a new project repository initialized by the template.
Once you have created the project, install dependencies and run the project in development mode:
cd my-app
npm install
npm run dev
This will start the development server on localhost:3000. Open it and click around.
You now have a fully functional Sapper project! To get started developing, consult sapper.svelte.dev.
By default, the template uses plain JavaScript. I have removed the setupTypeScript.js
script that comes with new Sapper projects, but theoretically it is possible to run this with TypeScript if you set it up on your own.
Sapper expects to find two directories in the root of your project — src
and static
.
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.
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:
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 routesrc/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
.src/routes/_helpers/datetime.js
and it would not create a /_helpers/datetime
route.This directory is where components used a mdsvex templates live. They can be configured in rollup.config.js
and will have the transformed markdown content passed to them as children.
Markdown files are transformed into Svelte components via mdsvex
, and are found by their file name and dynamically loaded as components into [slug].svelte
files using @rollup/plugin-dynamic-import-vars.
This directory is managed by Sapper and generated when building. It contains all the code you import from @sapper
modules.
The static directory contains static assets that should be served publicly. Files in this directory will be available directly under the root URL, e.g. an image.jpg
will be available as /image.jpg
.
The default service-worker.js will preload and cache these files, by retrieving a list of files
from the generated manifest:
import { files } from '@sapper/service-worker';
If you have static files you do not want to cache, you should exclude them from this list after importing it (and before passing it to cache.addAll
).
Static files are served using sirv.
Files from src/routes/blog/[slug]/_images
are copied into the static/images
directory using rollup-plugin-copy. The root of this directory is added to .gitignore
so images aren't tracked twice, but inside of static/images
there is a static/images/site-assets
directory that will be tracked to git. Images copied with the same name will overwrite each other, so please be careful.
This template uses Rollup to provide code-splitting and dynamic imports, as well as compiling your Svelte components. As long as you don't do anything daft, you can edit the configuration files to add whatever plugins you'd like.
To start a production version of your app, run npm run build && npm start
. This will disable live reloading, and activate the appropriate bundler plugins.
You can deploy your application to any environment that supports Node 10 or above. As an example, to deploy to Vercel Now when using sapper export
, run these commands:
npm install -g vercel
vercel
If your app can't be exported to a static site, you can use the vercel-sapper builder. You can find instructions on how to do so in its README.
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 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
Using Windows and WSL2?
If your project lives outside the WSL root directory, this limitation is known to cause live-reloading to fail. See this issue for details.
Sapper is in early development, and may have the odd rough edge here and there. Please be vocal over on the Sapper issue tracker.
If there are issues with this template specifically, issues can be filed here.