prerender-level-cache

Prerender plugin for level caching, to be used with the prerender node application from https://github.com/prerender/prerender.

How it works

This plugin will store all prerendered pages into a level database. There is currently no expiration functionality, which means that once a page is stored, future requests for prerendering a page will always be served from the cache if it's available and the page caches are never updated.

To get a fresh cache, the easiest is to set req.freshness = 0 from another prerender plugin. Alternatively, you can delete the cache directly in the LevelDB database.

How to use

In your local prerender project run:

$ npm install prerender-level-cache --save

Then in the server.js that initializes the prerender:

server.use(require('prerender-level-cache'));

Custom features

Level-party

The plugin uses the level-party module to get over the level multi-process restrictions.

Freshness

You can pass a per-request max age parameter to req.freshness, through other prerender plugins, to customize the cache freshness (set to one month by default):

Exemple:

// in another plugin placed before prerender-level-cache
module.exports = {
  requestReceived: function(req, res, next){
    // setting the freshness to one day
    req.freshness = 24*60*60*1000;
    next()
  }
}