83 lines
2.1 KiB
JavaScript
83 lines
2.1 KiB
JavaScript
var loadingDiv = document.getElementById('loading');
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var errorDiv = document.getElementById('error');
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var resultDiv = document.getElementById('result');
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const timeout = 10000;
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function getHistogram() {
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// Send XHR to totalTable
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loadingDiv.style.display = "";
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errorDiv.style.display = "none";
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let xhr = new XMLHttpRequest();
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xhr.timeout = timeout;
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xhr.onreadystatechange = function() {
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if (xhr.readyState === XMLHttpRequest.DONE) {
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if (xhr.status === 200) {
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setData(JSON.parse(xhr.responseText));
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} else {
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setError();
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}
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}
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};
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xhr.open('GET', '/histogram-data', true);
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xhr.send();
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}
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function setData(data) {
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loadingDiv.style.display = "none";
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errorDiv.style.display = "none";
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var barChartData = {
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labels: [],
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datasets: [{
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backgroundColor: 'rgba(54, 162, 235, 0.5)',
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borderColor: 'rgb(54, 162, 235, 1.0)',
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borderWidth: 1,
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label: 'Your lessons',
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data: [],
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}],
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};
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for (let key in data) {
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barChartData.labels.push(data[key].time);
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barChartData.datasets[0].data.push(data[key].count);
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}
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let canvas = document.createElement('canvas');
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let ctx = canvas.getContext('2d');
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document.getElementById('result').appendChild(canvas);
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new Chart(ctx, {
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type: 'bar',
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data: barChartData,
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options: {
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responsive: true,
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legend: {
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position: 'top',
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},
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title: {
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display: true,
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text: 'Histogram of times of lessons'
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},
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scales: {
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yAxes: [{
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ticks: {
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beginAtZero: true
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}
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}]
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}
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}
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}).update();
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console.log(barChartData);
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}
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function setError() {
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loadingDiv.style.display = "none";
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errorDiv.style.display = "";
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}
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document.getElementById('tryAgain').addEventListener('click', getHistogram);
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getHistogram();
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