gistfile1.coffee

#
# Barebones HTML caching with Redis
#

redis = require("redis")
client = redis.createClient()

app.get '/', (req, res, next) ->
  
  # Check if the request is cached
  client.get req.url, (err, cachedHtml) ->
    return next(err) if err
    return res.send(cachedHtml) if cachedHtml
    
    # Typical page rendering code
    fetchSomeThings (someThings) ->
      res.render 'index', { someThings: someThings }, (err, html) ->
      
        # Set the cache
        client.set(req.url, html)

#
# DRYed up with a helper
#

# lib/cache_helpers.coffee
redis = require("redis")
client = redis.createClient()

@renderCached = (req, res, next) ->
  client.get req.url, (err, html) ->
    return next(err) 
    return res.send(html) if html
    next()
    
@cache = (err, html) ->
  client.set(req.url, html)

# routes file
{ renderCached, cache } = require '../../lib/cacheHelpers'

app.get '/', renderCached, (req, res, next) ->
  fetchSomeThings (someThings) ->
    res.render 'index', { someThings: someThings }, cache
    
#
# Example in artwork routes
#

@mainPage = (req, res, next) ->
  
  # Check if the request is cached and render the cached html instead
  client.get req.url, (err, cachedHtml) ->
    return next(err) if err
    return res.send(cachedHtml) if cachedHtml
    
    # Otherwise go on with the normal fetch code
    artwork = new Artwork(id: req.params.id)
    artwork.fetch
      success: ->
        res.locals.sd.ARTWORK = artwork.toJSON()
        res.render 'main_page', artwork: artwork, (err, html) ->
      
          # Successful fetch, store the HTML in Redis and set a timeout to invalidate
          client.set(req.url, html)
          setTimeout (-> client.del(req.url)), 60 * 60 * 1000
          
      
      error: res.backboneError