defaultOptions =
# How long should it take for the bar to animate to a new
# point after receiving it
catchupTime: 100
# How quickly should the bar be moving before it has any progress
# info from a new source in %/ms
initialRate: .03
# What is the minimum amount of time the bar should be on the
# screen. Irrespective of this number, the bar will always be on screen for
# 33 * (100 / maxProgressPerFrame) + ghostTime ms.
minTime: 250
# What is the minimum amount of time the bar should sit after the last
# update before disappearing
ghostTime: 100
# Its easy for a bunch of the bar to be eaten in the first few frames
# before we know how much there is to load. This limits how much of
# the bar can be used per frame
maxProgressPerFrame: 20
# This tweaks the animation easing
easeFactor: 1.25
# Should pace automatically start when the page is loaded, or should it wait for `start` to
# be called? Always false if pace is loaded with AMD or CommonJS.
startOnPageLoad: true
# Should we restart the browser when pushState or replaceState is called? (Generally
# means ajax navigation has occured)
restartOnPushState: true
# Should we show the progress bar for every ajax request (not just regular or ajax-y page
# navigation)? Set to false to disable.
#
# If so, how many ms does the request have to be running for before we show the progress?
restartOnRequestAfter: 500
# What element should the pace element be appended to on the page?
target: 'body'
elements:
# How frequently in ms should we check for the elements being tested for
# using the element monitor?
checkInterval: 100
# What elements should we wait for before deciding the page is fully loaded (not required)
selectors: ['body']
eventLag:
# When we first start measuring event lag, not much is going on in the browser yet, so it's
# not uncommon for the numbers to be abnormally low for the first few samples. This configures
# how many samples we need before we consider a low number to mean completion.
minSamples: 10
# How many samples should we average to decide what the current lag is?
sampleCount: 3
# Above how many ms of lag is the CPU considered busy?
lagThreshold: 3
ajax:
# Which HTTP methods should we track?
trackMethods: ['GET']
# Should we track web socket connections?
trackWebSockets: true
# A list of regular expressions or substrings of URLS we should ignore (for both tracking and restarting)
ignoreURLs: []
now = ->
performance?.now?() ? +new Date
requestAnimationFrame = window.requestAnimationFrame or window.mozRequestAnimationFrame or
window.webkitRequestAnimationFrame or window.msRequestAnimationFrame
cancelAnimationFrame = window.cancelAnimationFrame or window.mozCancelAnimationFrame
if not requestAnimationFrame?
requestAnimationFrame = (fn) ->
setTimeout fn, 50
cancelAnimationFrame = (id) ->
clearTimeout id
runAnimation = (fn) ->
last = now()
tick = ->
diff = now() - last
if diff >= 33
# Don't run faster than 30 fps
last = now()
fn diff, ->
requestAnimationFrame tick
else
setTimeout tick, (33 - diff)
tick()
result = (obj, key, args...) ->
if typeof obj[key] is 'function'
obj[key](args...)
else
obj[key]
extend = (out, sources...) ->
for source in sources when source
for own key, val of source
if out[key]? and typeof out[key] is 'object' and val? and typeof val is 'object'
extend(out[key], val)
else
out[key] = val
out
avgAmplitude = (arr) ->
sum = count = 0
for v in arr
sum += Math.abs(v)
count++
sum / count
getFromDOM = (key='options', json=true) ->
el = document.querySelector "[data-pace-#{ key }]"
return unless el
data = el.getAttribute "data-pace-#{ key }"
return data if not json
try
return JSON.parse data
catch e
console?.error "Error parsing inline pace options", e
class Evented
on: (event, handler, ctx, once=false) ->
@bindings ?= {}
@bindings[event] ?= []
@bindings[event].push {handler, ctx, once}
once: (event, handler, ctx) ->
@on(event, handler, ctx, true)
off: (event, handler) ->
return unless @bindings?[event]?
if not handler?
delete @bindings[event]
else
i = 0
while i < @bindings[event].length
if @bindings[event][i].handler is handler
@bindings[event].splice i, 1
else
i++
trigger: (event, args...) ->
if @bindings?[event]
i = 0
while i < @bindings[event].length
{handler, ctx, once} = @bindings[event][i]
handler.apply(ctx ? @, args)
if once
@bindings[event].splice i, 1
else
i++
Pace = window.Pace or {}
window.Pace = Pace
extend Pace, Evented::
options = Pace.options = extend {}, defaultOptions, window.paceOptions, getFromDOM()
for source in ['ajax', 'document', 'eventLag', 'elements']
# true enables them without configuration, so we grab the config from the defaults
if options[source] is true
options[source] = defaultOptions[source]
class NoTargetError extends Error
class Bar
constructor: ->
@progress = 0
getElement: ->
if not @el?
targetElement = document.querySelector options.target
if not targetElement
throw new NoTargetError
@el = document.createElement 'div'
@el.className = "pace pace-active"
document.body.className = document.body.className.replace /pace-done/g, ''
document.body.className += ' pace-running'
@el.innerHTML = '''
<div class="pace-progress">
<div class="pace-progress-inner"></div>
</div>
<div class="pace-activity"></div>
'''
if targetElement.firstChild?
targetElement.insertBefore @el, targetElement.firstChild
else
targetElement.appendChild @el
@el
finish: ->
el = @getElement()
el.className = el.className.replace 'pace-active', ''
el.className += ' pace-inactive'
document.body.className = document.body.className.replace 'pace-running', ''
document.body.className += ' pace-done'
update: (prog) ->
@progress = prog
do @render
destroy: ->
try
@getElement().parentNode.removeChild(@getElement())
catch NoTargetError
@el = undefined
render: ->
if not document.querySelector(options.target)?
return false
el = @getElement()
transform = "translate3d(#{ @progress }%, 0, 0)"
for key in ['webkitTransform', 'msTransform', 'transform']
el.children[0].style[key] = transform
if not @lastRenderedProgress or @lastRenderedProgress|0 != @progress|0
# The whole-part of the number has changed
el.children[0].setAttribute 'data-progress-text', "#{ @progress|0 }%"
if @progress >= 100
# We cap it at 99 so we can use prefix-based attribute selectors
progressStr = '99'
else
progressStr = if @progress < 10 then "0" else ""
progressStr += @progress|0
el.children[0].setAttribute 'data-progress', "#{ progressStr }"
@lastRenderedProgress = @progress
done: ->
@progress >= 100
class Events
constructor: ->
@bindings = {}
trigger: (name, val) ->
if @bindings[name]?
for binding in @bindings[name]
binding.call @, val
on: (name, fn) ->
@bindings[name] ?= []
@bindings[name].push fn
_XMLHttpRequest = window.XMLHttpRequest
_XDomainRequest = window.XDomainRequest
_WebSocket = window.WebSocket
extendNative = (to, from) ->
for key of from::
try
if not to[key]? and typeof from[key] isnt 'function'
if typeof Object.defineProperty is 'function'
Object.defineProperty(to, key, {
get: ->
return from::[key];
,
configurable: true,
enumerable: true })
else
to[key] = from::[key]
catch e
ignoreStack = []
Pace.ignore = (fn, args...) ->
ignoreStack.unshift 'ignore'
ret = fn(args...)
ignoreStack.shift()
ret
Pace.track = (fn, args...) ->
ignoreStack.unshift 'track'
ret = fn(args...)
ignoreStack.shift()
ret
shouldTrack = (method='GET') ->
if ignoreStack[0] is 'track'
return 'force'
if not ignoreStack.length and options.ajax
if method is 'socket' and options.ajax.trackWebSockets
return true
else if method.toUpperCase() in options.ajax.trackMethods
return true
return false
# We should only ever instantiate one of these
class RequestIntercept extends Events
constructor: ->
super
monitorXHR = (req) =>
_open = req.open
req.open = (type, url, async) =>
if shouldTrack(type)
@trigger 'request', {type, url, request: req}
_open.apply req, arguments
window.XMLHttpRequest = (flags) ->
req = new _XMLHttpRequest(flags)
monitorXHR req
req
try
extendNative window.XMLHttpRequest, _XMLHttpRequest
if _XDomainRequest?
window.XDomainRequest = ->
req = new _XDomainRequest
monitorXHR req
req
try
extendNative window.XDomainRequest, _XDomainRequest
if _WebSocket? and options.ajax.trackWebSockets
window.WebSocket = (url, protocols) =>
if protocols?
req = new _WebSocket(url, protocols)
else
req = new _WebSocket(url)
if shouldTrack('socket')
@trigger 'request', {type: 'socket', url, protocols, request: req}
req
try
extendNative window.WebSocket, _WebSocket
_intercept = null
getIntercept = ->
if not _intercept?
_intercept = new RequestIntercept
_intercept
shouldIgnoreURL = (url) ->
for pattern in options.ajax.ignoreURLs
if typeof pattern is 'string'
if url.indexOf(pattern) isnt -1
return true
else
if pattern.test(url)
return true
return false
# If we want to start the progress bar
# on every request, we need to hear the request
# and then inject it into the new ajax monitor
# start will have created.
getIntercept().on 'request', ({type, request, url}) ->
return if shouldIgnoreURL(url)
if not Pace.running and (options.restartOnRequestAfter isnt false or shouldTrack(type) is 'force')
args = arguments
after = options.restartOnRequestAfter or 0
if typeof after is 'boolean'
after = 0
setTimeout ->
if type is 'socket'
stillActive = request.readyState < 2
else
stillActive = 0 < request.readyState < 4
if stillActive
Pace.restart()
for source in Pace.sources
if source instanceof AjaxMonitor
source.watch args...
break
, after
class AjaxMonitor
constructor: ->
@elements = []
getIntercept().on 'request', => @watch arguments...
watch: ({type, request, url}) ->
return if shouldIgnoreURL(url)
if type is 'socket'
tracker = new SocketRequestTracker(request)
else
tracker = new XHRRequestTracker(request)
@elements.push tracker
class XHRRequestTracker
constructor: (request) ->
@progress = 0
if window.ProgressEvent?
# We're dealing with a modern browser with progress event support
size = null
request.addEventListener 'progress', (evt) =>
if evt.lengthComputable
@progress = 100 * evt.loaded / evt.total
else
# If it's chunked encoding, we have no way of knowing the total length of the
# response, all we can do is increment the progress with backoff such that we
# never hit 100% until it's done.
@progress = @progress + (100 - @progress) / 2
, false
for event in ['load', 'abort', 'timeout', 'error']
request.addEventListener event, =>
@progress = 100
, false
else
_onreadystatechange = request.onreadystatechange
request.onreadystatechange = =>
if request.readyState in [0, 4]
@progress = 100
else if request.readyState is 3
@progress = 50
_onreadystatechange?(arguments...)
class SocketRequestTracker
constructor: (request) ->
@progress = 0
for event in ['error', 'open']
request.addEventListener event, =>
@progress = 100
, false
class ElementMonitor
constructor: (options={}) ->
@elements = []
options.selectors ?= []
for selector in options.selectors
@elements.push new ElementTracker selector
class ElementTracker
constructor: (@selector) ->
@progress = 0
@check()
check: ->
if document.querySelector(@selector)
@done()
else
setTimeout (=> @check()),
options.elements.checkInterval
done: ->
@progress = 100
class DocumentMonitor
states:
loading: 0
interactive: 50
complete: 100
constructor: ->
@progress = @states[document.readyState] ? 100
_onreadystatechange = document.onreadystatechange
document.onreadystatechange = =>
if @states[document.readyState]?
@progress = @states[document.readyState]
_onreadystatechange?(arguments...)
class EventLagMonitor
constructor: ->
@progress = 0
avg = 0
samples = []
points = 0
last = now()
interval = setInterval =>
diff = now() - last - 50
last = now()
samples.push diff
if samples.length > options.eventLag.sampleCount
samples.shift()
avg = avgAmplitude samples
if ++points >= options.eventLag.minSamples and avg < options.eventLag.lagThreshold
@progress = 100
clearInterval interval
else
@progress = 100 * (3 / (avg + 3))
, 50
class Scaler
constructor: (@source) ->
@last = @sinceLastUpdate = 0
@rate = options.initialRate
@catchup = 0
@progress = @lastProgress = 0
if @source?
@progress = result(@source, 'progress')
tick: (frameTime, val) ->
val ?= result(@source, 'progress')
if val >= 100
@done = true
if val == @last
@sinceLastUpdate += frameTime
else
if @sinceLastUpdate
@rate = (val - @last) / @sinceLastUpdate
@catchup = (val - @progress) / options.catchupTime
@sinceLastUpdate = 0
@last = val
if val > @progress
# After we've got a datapoint, we have catchupTime to
# get the progress bar to reflect that new data
@progress += @catchup * frameTime
scaling = (1 - Math.pow(@progress / 100, options.easeFactor))
# Based on the rate of the last update, we preemptively update
# the progress bar, scaling it so it can never hit 100% until we
# know it's done.
@progress += scaling * @rate * frameTime
@progress = Math.min(@lastProgress + options.maxProgressPerFrame, @progress)
@progress = Math.max(0, @progress)
@progress = Math.min(100, @progress)
@lastProgress = @progress
@progress
sources = null
scalers = null
bar = null
uniScaler = null
animation = null
cancelAnimation = null
Pace.running = false
handlePushState = ->
if options.restartOnPushState
Pace.restart()
# We reset the bar whenever it looks like an ajax navigation has occured.
if window.history.pushState?
_pushState = window.history.pushState
window.history.pushState = ->
handlePushState()
_pushState.apply window.history, arguments
if window.history.replaceState?
_replaceState = window.history.replaceState
window.history.replaceState = ->
handlePushState()
_replaceState.apply window.history, arguments
SOURCE_KEYS =
ajax: AjaxMonitor
elements: ElementMonitor
document: DocumentMonitor
eventLag: EventLagMonitor
do init = ->
Pace.sources = sources = []
for type in ['ajax', 'elements', 'document', 'eventLag']
if options[type] isnt false
sources.push new SOURCE_KEYS[type](options[type])
for source in options.extraSources ? []
sources.push new source(options)
Pace.bar = bar = new Bar
# Each source of progress data has it's own scaler to smooth its output
scalers = []
# We have an extra scaler for the final output to keep things looking nice as we add and
# remove sources
uniScaler = new Scaler
Pace.stop = ->
Pace.trigger 'stop'
Pace.running = false
bar.destroy()
# Not all browsers support cancelAnimationFrame
cancelAnimation = true
if animation?
cancelAnimationFrame? animation
animation = null
init()
Pace.restart = ->
Pace.trigger 'restart'
Pace.stop()
Pace.start()
Pace.go = ->
Pace.running = true
bar.render()
start = now()
cancelAnimation = false
animation = runAnimation (frameTime, enqueueNextFrame) ->
# Every source gives us a progress number from 0 - 100
# It's up to us to figure out how to turn that into a smoothly moving bar
#
# Their progress numbers can only increment. We try to interpolate
# between the numbers.
remaining = 100 - bar.progress
count = sum = 0
done = true
# A source is composed of a bunch of elements, each with a raw, unscaled progress
for source, i in sources
scalerList = scalers[i] ?= []
elements = source.elements ? [source]
# Each element is given it's own scaler, which turns its value into something
# smoothed for display
for element, j in elements
scaler = scalerList[j] ?= new Scaler element
done &= scaler.done
continue if scaler.done
count++
sum += scaler.tick(frameTime)
avg = sum / count
bar.update uniScaler.tick(frameTime, avg)
if bar.done() or done or cancelAnimation
bar.update 100
Pace.trigger 'done'
setTimeout ->
bar.finish()
Pace.running = false
Pace.trigger 'hide'
, Math.max(options.ghostTime, Math.max(options.minTime - (now() - start), 0))
else
enqueueNextFrame()
Pace.start = (_options) ->
extend options, _options
Pace.running = true
try
bar.render()
catch NoTargetError
# It's usually possible to render a bit before the document declares itself ready
if not document.querySelector('.pace')
setTimeout Pace.start, 50
else
Pace.trigger 'start'
Pace.go()
if typeof define is 'function' and define.amd
# AMD
define ['pace'], -> Pace
else if typeof exports is 'object'
# CommonJS
module.exports = Pace
else
# Global
if options.startOnPageLoad
Pace.start()
|