spa-router

Express-like routing for Single Page Apps

Use if you want something very simple and basic, there are plenty of more fully-featured solutions out there

npm install @mojule/spa-router

Note that although intended to be used in the browser, there is no code in the package that is specific to either node or the browser, so it can be used anywhere to do Express-like routing

basic example

<header>
  <a href="#hello">Hello</a>
</header>
<main></main>

const { App } = require( '@mojule/spa-router' )

const hashChange = new Event( 'hashchange' )

document.addEventListener( 'DOMContentLoaded', () => {
  const main = document.querySelector( 'main' )

  const send = node => {
    main.innerHTML = ''
    main.appendChild( node )
  }

  const redirect = path => {
    window.location.hash = `#${ path }`
    window.dispatchEvent( hashChange )
  }

  const app = App( send, redirect )

  app.get( 'hello', ( req, res ) => {
    const hello = document.createTextNode( 'Hello' )

    res.send( hello )
  } )

  window.addEventListener( 'hashchange', () => {
    const { hash } = window.location
    const path = hash.replace( '#', '' )

    try {
      app.router( path )
    } catch( err ){
      window.alert( err.message )
    }
  } )

  if ( location.hash !== '' ) {
    window.dispatchEvent( hashChange )
  }
} )

app factory

A factory function is exported to create the app instance - unlike Express, it is a named export, and unlike Express, it requires some arguments

In express:

const express = require( 'express' )

const app = express()

Here:

const { App } = require( '@mojule/spa-router' )

const app = App( send, redirect )

send is a function that takes a single argument for the content being sent, and is placed directly on the res object passed to handlers (see example above)

redirect is a function that takes a single argument for the path to redirect to and is also placed directly on the res object - it is up to you to call app.router when redirect is called (see the example above where we use the hash change event to wire everything up)

app.get

Like express app.get, see below

app.use

Like express app.use, see below

app.router

app.router( path )

Causes the app to call the appropriate handlers for the path, like Express does with an incoming HTTP request - use in conjunction with the redirect function, see example above

What it supports

You should know how to use Express already - this is a very small subset of Express - if functionality is not listed below, assume it doesn't exist

method routing

Only app.get - open to PRs but a discussion would have to be had about how to handle eg post

route params

Same as Express (uses the same library)

app.get( 'hello/:name', ( req, res ) => {
  const { name } = req.params

  const hello = document.createTextNode( `Hello ${ name }` )

  res.send( hello )
} )

multiple handlers

  const logHandler = ( req, res, next ) => {
    console.log( req )
    next()
  }

  app.get(
    'hello',
    logHandler,
    ( req, res ) => {
      const hello = document.createTextNode( 'Hello' )

      res.send( hello )
    }
  )

basic middleware

app.use( ( req, res, next ) => {
  const { send } = res

  // wrap whatever subsequent handlers send in a div
  res.send = node => {
    const div = document.createElement( 'div' )

    div.appendChild( node )

    send( div )
  }

  next()
})

Skip all other middleware and go straight to route handlers:

( req, res, next ) => {
  console.log( 'skipping other middleware' )

  next( 'route' )
}

req

Only has req.path and req.params

res

Only has res.send( content ) and res.redirect( path )

Using from TypeScript

It exports all of its own types, no need to install a types package

The response sent by res.send can be typed, if you omit it will default to any

If you pass the App factory function a typed send function it will imply the response type from that:

// ... other code etc

const send = ( content: HTMLElement ) => {
  main.innerHTML = ''
  main.appendChild( content )
}

const app = App( send, redirect )

app.get( ( req, res ) => {
  const content: string = 'Hello'

  // you will get a type error here, expected HTMLElement
  res.send( content )
} )

Or you can explicity type it:

const app = App<HTMLElement>( send, redirect )

license

MIT License

Copyright (c) 2019 Nik Coughlin

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.