nx-seo

An express middleware, that pre-renders NX apps when the request user-agent is a crawler. It also removes all the scripts from the page after rendering and before sending the final HTML.

Installation

$ npm install @risingstack/nx-seo

Platform support

NodeJS 6 and above.

Usage

The below code creates a simple express server for NX. It servers static assets if found. Then it detects crawler user-agents with the seo middleware and prerenders pages for them. Finally it server the main page of the app for bootstrapping, if non of the above conditions are met.

const express = require('express')
const app = express()
const server = require('http').createServer(app)
const seo = require('@risingstack/nx-seo')

const port = 8080
const ip = "127.0.0.1"
const mainFile = '/app.html'

app.use(express.static(__dirname))
app.use(seo({ timeout: 5, debug: true }))
app.use((req, res, next) => {
  if (req.accepts('html')) res.sendFile(__dirname + mainFile)
})

server.listen(port, ip)

Configuration

You can pass a config object to seo as argument. It currently has two options. debug is a boolean, which defaults to false. If you set it to true errors during the pre-render will be forwarded to the NodeJS console. timeout is a number, which defaults to 0. It applies a timeout to allow pre-rendering deferred scripts before sending the result. Use it if your page doesn't render for the crawlers.

Contributing

Bug fixes, tests and new ideas are always welcome. Thanks!