JSFiddle - React, Tailwind, and code Playground

by sergiu079

HTML

<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.16.0/moment.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.4.0/Chart.min.js"></script>
<div class="panel"><canvas id="canvas1"></canvas></div>
<div class="panel"><canvas id="canvas2"></canvas></div>

CSS

body {
  background: #ddd;
}
.panel {
  padding-left: 5px;
  background: #fff;
  box-shadow: 0 0 5px 0 #999;
  border-radius: 5px;
  margin: 0 auto;
  width: 100%;
  height: 300px;
  margin-top: 2em;
  max-width: 600px;
}

JavaScript

const DATEFORMAT = 'hour';
const DATEFORMATS = {
  'hour': 'hh:mma',
  'day': 'MMM DD',
  'week': 'MMM DD',
  'month': 'MMM'
};

drawChart('canvas1', 10, true);
drawChart('canvas2', 30, false);

function drawChart(canvasId, totalValues, hideLastXLabel) {
  new Chart(document.querySelector('#'+canvasId), {
      type: 'line',
      data: getData(totalValues),
      options: {
          layout: {
            padding: {
              right: 10
            }
          },
          scales: {
            yAxes: [{
              ticks: {
                beginAtZero:true
              }
            }],
            xAxes: [{
              gridLines : {
                display : true
              },
              ticks : {
                callback: (value,index,values) => {
                  // don't show last tick label
                  if (hideLastXLabel && index+1 >= values.length) {
                    return '';
                  }

									return DATEFORMATS[DATEFORMAT]? moment(value).format(DATEFORMATS[DATEFORMAT]) : value.toString();
                }
              }
            }]
          }
      }
  });
}

// get hourly data
function getData(total) {
  var data = {
    labels: [],
    datasets: [{
      data: [],
      label: 'Data',
      lineTension: 0,
      backgroundColor:"rgba(128, 203, 196,0.45)",
      borderColor:"#80cbc4",
      pointBackgroundColor: "#80cbc4",
      pointBorderWidth: 2,
      hoverBorderColor:"#80cbc4",
      pointBorderColor:"#fff",
      pointRadius: 5,
      pointHoverRadius:5
    }],
  }

  // calculate start/end dates for hourly increment additions
  var end = Date.now();
  var start = total < 2? end : end-((total-1)*1000*60*60); // subtract total-1 hours from current time


  for (var i=0; i<total; i++) {
    // Add label from start and incrementing by hour
    data.labels.push(start+(i*1000*60*60));
    
    // Add random value 0-20
    data.datasets[0].data.push(Math.round(20*Math.random()));
  }

  return data;
}