# Rack.coffee - A Rack is an asset manager
# Pull in our dependencies
async = require 'async'
pkgcloud = require 'pkgcloud'
fs = require 'fs'
jade = require 'jade'
pathutil = require 'path'
{BufferStream, extend} = require('./util')
{EventEmitter} = require 'events'
# Rack - Manages multiple assets
class exports.Rack extends EventEmitter
constructor: (assets, options) ->
super()
# Set a default options object
options ?= {}
# Max age for HTTP Cache-Control
@maxAge = options.maxAge
# Allow non-hahshed urls to be cached
@allowNoHashCache = options.allowNoHashCache
# Once complete always set the completed flag
@on 'complete', =>
@completed = true
# If someone listens for the "complete" event
# check if it's already been called
@on 'newListener', (event, listener) =>
if event is 'complete' and @completed is true
listener()
# Listen for the error event, throw if no listeners
@on 'error', (error) =>
console.log error
@hasError = true
@currentError = error
# Give assets in the rack a reference to the rack
for asset in assets
asset.rack = this
# Create a flattened array of assets
@assets = []
# Do this in series for dependency conflicts
async.forEachSeries assets, (asset, next) =>
# Listen for any asset error events
asset.on 'error', (error) =>
next error
# Wait for assets to finish completing
asset.on 'complete', =>
# This is necessary because of asset recompilation
return if @completed
# If the asset has contents, it's a single asset
if asset.contents?
@assets.push asset
# If it has assets, then it's multi-asset
if asset.assets?
@assets = @assets.concat asset.assets
next()
# This tells our asset to start
asset.emit 'start'
# Handle any errors for the assets
, (error) =>
return @emit 'error', error if error?
@emit 'complete'
# Makes the rack function as express middleware
handle: (request, response, next) ->
response.locals assets: this
if request.url.slice(0,11) is '/asset-rack'
return @handleAdmin request, response, next
if @hasError
for asset in @assets
check = asset.checkUrl request.path
return asset.respond request, response if check
return response.redirect '/asset-rack/error'
handle = =>
for asset in @assets
check = asset.checkUrl request.path
return asset.respond request, response if check
next()
if @completed
handle()
else @on 'complete', handle
handleError: (request, response, next) ->
# No admin in production for now
return next() if process.env.NODE_ENV is 'production'
errorPath = pathutil.join __dirname, 'admin/templates/error.jade'
fs.readFile errorPath, 'utf8', (error, contents) =>
return next error if error?
compiled = jade.compile contents,
filename: errorPath
response.send compiled
stack: @currentError.stack.split '\n'
handleAdmin: (request, response, next) ->
# No admin in production for now
return next() if process.env.NODE_ENV is 'production'
split = request.url.split('/')
if split.length > 2
path = request.url.replace '/asset-rack/', ''
if path is 'error'
return @handleError request, response, next
response.sendfile pathutil.join __dirname, 'admin', path
else
adminPath = pathutil.join __dirname, 'admin/templates/admin.jade'
fs.readFile adminPath, 'utf8', (error, contents) =>
return next error if error?
compiled = jade.compile contents,
filename: adminPath
response.send compiled
assets: @assets
# Writes a config file of urls to hashed urls for CDN use
writeConfigFile: (filename) ->
config = {}
for asset in @assets
config[asset.url] = asset.specificUrl
fs.writeFileSync filename, JSON.stringify(config)
# Deploy assets to a CDN
deploy: (options, next) ->
options.keyId = options.accessKey
options.key = options.secretKey
deploy = =>
client = pkgcloud.storage.createClient options
assets = @assets
# Big time hack for rackspace, first asset doesn't upload, very strange.
# Might be bug with pkgcloud. This hack just uploads the first file again
# at the end.
assets = @assets.concat @assets[0] if options.provider is 'rackspace'
async.forEachSeries assets, (asset, next) =>
stream = null
headers = {}
if asset.gzip
stream = new BufferStream asset.gzipContents
headers['content-encoding'] = 'gzip'
else
stream = new BufferStream asset.contents
url = asset.specificUrl.slice 1, asset.specificUrl.length
for key, value of asset.headers
headers[key] = value
headers['x-amz-acl'] = 'public-read' if options.provider is 'amazon'
clientOptions =
container: options.container
remote: url
headers: headers
stream: stream
client.upload clientOptions, (error) ->
return next error if error?
next()
, (error) =>
if error?
return next error if next?
throw error
if options.configFile?
@writeConfigFile options.configFile
next() if next?
if @completed
deploy()
else @on 'complete', deploy
# Creates an HTML tag for a given asset
tag: (url) ->
for asset in @assets
return asset.tag() if asset.url is url
throw new Error "No asset found for url: #{url}"
# Gets the hashed url for a given url
url: (url) ->
for asset in @assets
return asset.specificUrl if url is asset.url
# Extend the class for javascript
@extend: extend
# The ConfigRack uses a json file and a hostname to map assets to a url
# without actually compiling them
class ConfigRack
constructor: (options) ->
# Check for required options
throw new Error('options.configFile is required') unless options.configFile?
throw new Error('options.hostname is required') unless options.hostname?
# Setup our options
@assetMap = require options.configFile
@hostname = options.hostname
# For hooking up as express middleware
handle: (request, response, next) ->
response.locals assets: this
for url, specificUrl of @assetMap
if request.path is url or request.path is specificUrl
# Redirect to the CDN, the config does not have the files
return response.redirect "//#{@hostname}#{specificUrl}"
next()
# Simple function to get the tag for a url
tag: (url) ->
switch pathutil.extname(url)
when '.js'
tag = "\n"
when '.css'
return "\n"
# Get the hashed url for a given url
url: (url) ->
return "//#{@hostname}#{@assetMap[url]}"
# Shortcut function
exports.fromConfigFile = (options) ->
return new ConfigRack(options)