[Chartjs]-Ability to rotate y axis title in chart.js

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4👍

✅

You can use a custom plugin, to make space you first need to increase the padding on the left, after that you can calculate the correct position by taking the average of the top and bottom y’s of the chart area.

Also you should not include chart.js 2 times. When chart.js updates to V4 you will have V4 and V3 installed which will give unwanted behaviour.

Example:

const customTitle = {
  id: 'customTitle',
  beforeLayout: (chart, args, opts) => {
    const {
      display,
      font
    } = opts;
    if (!display) {
      return;
    }

    const {
      ctx
    } = chart;
    ctx.font = font || '12px "Helvetica Neue", Helvetica, Arial, sans-serif'

    const {
      width
    } = ctx.measureText(opts.text);
    chart.options.layout.padding.left = width * 1.1;
  },
  afterDraw: (chart, args, opts) => {
    const {
      font,
      text,
      color
    } = opts;
    const {
      ctx,
      chartArea: {
        top,
        bottom,
        left,
        right
      }
    } = chart;

    if (opts.display) {
      ctx.fillStyle = color || Chart.defaults.color
      ctx.font = font || '12px "Helvetica Neue", Helvetica, Arial, sans-serif'
      ctx.fillText(text, 3, (top + bottom) / 2)
    }
  }
}

const labels = ['2021-06-07 00:00:00', '2021-06-08 00:00:00', '2021-06-09 00:00:00'];

const data = {
  labels: labels,
  datasets: [{
    label: 'Fixed defects',
    backgroundColor: 'rgb(0, 255, 0)',
    borderColor: 'rgb(0, 255, 0)',
    data: ['2', '73', '34'],
    barThickness: 5
  }, {
    label: 'Open defects',
    backgroundColor: 'rgb(255, 0, 0)',
    borderColor: 'rgb(255, 0, 0)',
    data: ['0', '5', '2'],
    barThickness: 5

  }]
};

const config = {
  type: 'bar',
  data: data,
  options: {
    scales: {
      x: {
        min: '2021-06-07 00:00:00',
        max: '2021-09-10 00:00:00',
        type: 'time',
        time: {
          unit: 'week'
        },
        stacked: true,
      },
      y: {
        stacked: true,
      }
    },
    plugins: {
      customTitle: {
        display: true,
        text: 'Number of defects',
        color: 'blue'
      }
    }
  },
  plugins: [customTitle]
};

const myChart = new Chart(
  document.getElementById('myChart'),
  config
);
<!DOCTYPE html>
<meta charset="utf-8">

<script src="https://cdn.jsdelivr.net/npm/chart.js@^3"></script>
<script src="https://cdn.jsdelivr.net/npm/moment@^2"></script>
<script src="https://cdn.jsdelivr.net/npm/chartjs-adapter-moment@^1"></script>

<body>
  <div>
    <canvas height="100px" id="myChart"></canvas>
  </div>
</body>

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