Javascript和人力車。我如何更新實時流？

Question

如何使用實時流更新人力車數據？

我按如下步驟啓動一個圖表。

for (var i = 0; i < json_data.length; i++) { 
    meta = json_data[i]; 
    seriesJsonData.push({color: palette.color(),data: meta['series'],name: meta['name']}); 
} 
var graph = new Rickshaw.Graph({ 
    element: document.getElementById("chart"), 
    width: 900, 
    height: 500, 
    renderer: 'area', 
    stroke: true, 
    series: seriesJsonData 
}); 

然後我想要回調來獲取這種格式的數據。

//new data to plot. 
setInterval(function() { 
    // data = mycallback('ajax_time_series/'); 
    data = {y: 0.013342943046016261, x: 1362914220}; 
    graph.series.addData(data); 
    graph.update(); 
}, 3000); 

json_data = [{"series": [{y: 0.013342943046016261, x: 1362914220}, {y: 0.03332711471721182, x: 1362914280}, {y: 0.01995987637052034, x: 1362914340}, {y: 0.02667808501229039, x: 1362914400}, {y: 0.026667576407988548, x: 1362914460}, {y: 0.02666090465447435, x: 1362914520}, {y: 0.039902022061890564, x: 1362914580}, {y: 0.040065222851502304, x: 1362914640}, {y: 0.026725544622339118, x: 1362914700}, {y: 0.03328597880035014, x: 1362914760}, {y: 0.020025583265634844, x: 1362914820}, {y: 0.013351483328567889, x: 1362914880}, {y: 0.013327807174645642, x: 1362914940}, {y: 0.03327930933245091, x: 1362915000}, {y: 0.060011496243413356, x: 1362915060}, {y: 0.026726823599964183, x: 1362915120}, {y: 0.06625748681407234, x: 1362915180}, {y: 0.08716853007016215, x: 1362915240}, {y: 0.019958925851731625, x: 1362915300}, {y: 0.026628071716283376, x: 1362915360}, {y: 0.053539335295842476, x: 1362915420}, {y: 0.013329419200217766, x: 1362915480}, {y: 0.020005110867173173, x: 1362915540}, {y: 0.03985835992510624, x: 1362915600}, {y: 0.04009389940367332, x: 1362915660}, {y: 0.020015945088387825, x: 1362915720}, {y: 0.02661011443819408, x: 1362915780}, {y: 0.06656881334811096, x: 1362915840}, {y: 0.04690556277785193, x: 1362915900}, {y: 0.03326433994636323, x: 1362915960}, {y: 0.02670133346693278, x: 1362916020}, {y: 0.033335701795225714, x: 1362916080}, {y: 0.020001391989344027, x: 1362916140}, {y: 0.02000903195967164, x: 1362916200}, {y: 0.013308784414422375, x: 1362916260}, {y: 0.058279492803009744, x: 1362916320}, {y: 0.034243644495436376, x: 1362916380}, {y: 0.020081534665136593, x: 1362916440}, {y: 0.026653921622562717, x: 1362916500}, {y: 0.0199648119499449, x: 1362916560}, {y: 0.03338215889686262, x: 1362916620}, {y: 0.04659716637539024, x: 1362916680}, {y: 0.033199969663029336, x: 1362916740}, {y: 0.020053008656297493, x: 1362916800}, {y: 0.020083574882737414, x: 1362916860}, {y: 0.013338712371294185, x: 1362916920}, {y: 0.013285462289789874, x: 1362916980}, {y: 0.03342980523147545, x: 1362917040}, {y: 0.013318560614522242, x: 1362917100}, {y: 0.020054761094019935, x: 1362917160}, {y: 0.02649323226604952, x: 1362917220}, {y: 0.08046447455222104, x: 1362917280}, {y: 0.033380214683152935, x: 1362917340}, {y: 0.01998459181555401, x: 1362917400}, {y: 0.11263974301203006, x: 1362917460}, {y: 0.03351645707155687, x: 1362917520}, {y: 0.02667373118205504, x: 1362917580}, {y: 0.020004237840478896, x: 1362917640}, {y: 0.0867493421006396, x: 1362917700}], "name": "cpuUsage"}]; 

我將有多個系列的更新。我的圖表不更新，我不理解要更新的文檔。

另外...我不承諾人力車。有沒有一個實時流JS庫有良好的文檔？人力車看起來很漂亮，但實時記錄很差。

Answer 1

我想，讓你知道我的解決方法是：

1. 保存圖表DIV供以後使用的內部HTML（圖表已經呈現後，內部HTML改變）

2. 添加數據時，將其添加到稍後可以訪問的數組中。

3. 正常情況下使用數組數組呈現圖表。

4. 當您需要添加數據時，將數據添加到包含您的數據的陣列並從頭開始重新生成圖表。只有在再次渲染之前將原始html再次插入到圖表div中，才能執行此操作。

這與8點的圖表，每5秒鐘更新一次，每圖表20個數據點效果很好。它幾乎不佔用資源。我相信如果增加數據點數量或使用高級渲染選項，它將需要很多。

我應該得到解決這個問題的諾貝爾獎。

Answer 2

對於那些後面的人，FixedDuration series可能是你想要的。

除了在this example demonstrating real time updates with a fixed window，it's been around since before the v1.1 release in August 2012之外，它似乎沒有任何記載。

下面是他們的例如產生積代碼：

var tv = 250; 

// instantiate our graph! 
var graph = new Rickshaw.Graph({ 
    element: document.getElementById("chart"), 
    width: 900, 
    height: 500, 
    renderer: 'line', 
    series: new Rickshaw.Series.FixedDuration([{ name: 'one' }], undefined, { 
     timeInterval: tv, 
     maxDataPoints: 100, 
     timeBase: new Date().getTime()/1000 
    }) 
}); 

graph.render(); 

// add some data every so often 

var i = 0; 
var iv = setInterval(function() { 

    var data = { one: Math.floor(Math.random() * 40) + 120 }; 

    var randInt = Math.floor(Math.random()*100); 
    data.two = (Math.sin(i++/40) + 4) * (randInt + 400); 
    data.three = randInt + 300; 

    graph.series.addData(data); 
    graph.render(); 

}, tv);