Annotations

Annotations is an umbrella term that includes several Grafana artifacts, as follows:

• Native Annotations
• Alerts
• Annotations Queries

We explained the differences between different types of annotations in the how-to tutorial within our Grafana Crash Course.

Mark Lines

The Business Charts panel displays annotations with mark lines. Data for mark lines is retrieved from the context.panel.data.annotations object.

Annotations in the Business Charts look similar to the Time Series panels.

Example

const annotations = [];
context.panel.data.annotations.map((a) => {
  a.source.forEach((source) =>
    annotations.push({
      xAxis: source.time,
      label: source.text,
      lineStyle: {
        color: source.color,
        width: 2,
      },
    })
  );
});

/**
 * Data Sources
 */
const series = context.panel.data.series.map((s) => {
  const sData = s.fields.find((f) => f.type === "number").values;
  const sTime = s.fields.find((f) => f.type === "time").values;

  return {
    name: s.refId,
    type: "line",
    showSymbol: false,
    areaStyle: {
      opacity: 0.1,
    },
    lineStyle: {
      width: 1,
    },
    data: sData.map((d, i) => [sTime[i], d.toFixed(2)]),
    markLine: {
      data: annotations,
      label: {
        show: false,
      },
      symbol: ["none", "none"],
    },
  };
});

/**
 * Enable Data Zoom by default
 */
setTimeout(
  () =>
    context.panel.chart.dispatchAction({
      type: "takeGlobalCursor",
      key: "dataZoomSelect",
      dataZoomSelectActive: true,
    }),
  500
);

/**
 * Update Time Range on Zoom
 */
context.panel.chart.on("datazoom", function (params) {
  const startValue = params.batch[0]?.startValue;
  const endValue = params.batch[0]?.endValue;
  context.grafana.locationService.partial({ from: startValue, to: endValue });
});

/**
 * Options
 */
return {
  backgroundColor: "transparent",
  tooltip: {
    trigger: "axis",
  },
  legend: {
    left: "0",
    bottom: "0",
    data: context.panel.data.series.map((s) => s.refId),
    textStyle: {
      color: "rgba(128, 128, 128, .9)",
    },
  },
  toolbox: {
    feature: {
      dataZoom: {
        yAxisIndex: "none",
        icon: {
          zoom: "path://",
          back: "path://",
        },
      },
      saveAsImage: {},
    },
  },
  xAxis: {
    type: "time",
  },
  yAxis: {
    type: "value",
    min: 0,
  },
  grid: {
    left: "1%",
    right: "1%",
    top: "2%",
    bottom: 24,
    containLabel: true,
  },
  series,
};