サーバーログでイベントトラッキングする用のJSライブラリ

evTrack.coffee

class EvTrack 
    constructor: (url)->
        @url = url
        @opt = {
            category : ""
            action : ""
            label : ""
            value : ""
        }
        @optName = {
            category : "cat"
            action : "act"
            label : "lab"
            value : "val"
        }

    begin: (param) ->
        objBody = document.getElementsByTagName("body").item(0)
        ele = document.createElement("img")
        ele.src = @url + "?" + param
        objBody.appendChild(ele)

    makeParam: ()->
        str = "r=#{Math.round(Math.random() * (new Date).getTime() / 1000)}"
        str += "&#{@optName['category']}=#{encodeURIComponent(@opt['category'])}"
        str += "&#{@optName['action']}=#{encodeURIComponent(@opt['action'])}"
        str += "&#{@optName['label']}=#{encodeURIComponent(@opt['label'])}"
        if @opt['value'] != "" && @opt["value"]?
            str += "&#{@optName['value']}=#{encodeURIComponent(@opt['value'])}"
        return str

    parseArr : (arr)->
        if (arr.length == 3 || arr.length == 4)
            @opt = {
                category : arr[0]
                action : arr[1]
                label : arr[2]
            }
            @opt.value = arr[3] if arr[3]?
        return @opt

    track : (arr)->
        this.parseArr(arr) if arr?
        param = this.makeParam()
        this.begin(param)
        this.clear()
        return false
    
    clear : ()->
        @opt = {
            category : ""
            action : ""
            label : ""
            value : ""
        }

#ビーコン画像の置いてある場所を指定
url = "b.gif"
window._evTrac = new EvTrack(url)