XYChart: Add support for x=time (#106459)

* XYChart: Add support for x=time

* prettier

* Add time axis demo to provisioned dashboard for XY

* Add details about time fields to the documentation

---------

Co-authored-by: Kristina Durivage <kristina.durivage@grafana.com>

docs/sources/panels-visualizations/visualizations/xy-chart/index.md

@@ -65,7 +65,7 @@ XY charts provide a way to visualize arbitrary x and y values in a graph so that
 
 ## Supported data formats
 
-You can use any type of tabular data with at least two numeric fields in an xy chart. This type of visualization doesn't require time data.
+You can use any type of tabular data with at least two numeric fields in an xy chart. The x field can be a time field. This type of visualization doesn't require time data, but it can be used.
 
 ## Configuration options
 
@@ -117,7 +117,7 @@ When you select **Auto** as your series mapping mode, the following options are
 | Option | Description |
 | ------ | ----------- |
 | Frame | By default, an xy chart displays all data frames. You can filter to select only one frame. |
-| [X field](#x-field) | Select which field or fields x represents. By default, this is the first number field in each data frame. For an example of this in **Auto** mode, refer to the [X field section](#x-field). |
+| [X field](#x-field) | Select which field or fields x represents. By default, this is the first number or time field in each data frame. For an example of this in **Auto** mode, refer to the [X field section](#x-field). |
 | [Y field](#y-field) | After the x-field is set, by default, all the remaining number fields in the data frame are designated as the y-fields. You can use this option to explicitly choose which fields to use for y. For more information on how to use this in **Auto** mode, refer to the [Y field section](#y-field). |
 
 <!-- prettier-ignore-end -->
@@ -145,7 +145,7 @@ In **Manual** mode, these fields are required:
 
 #### X field
 
-In **Auto** series mapping mode, select which field or fields x represents. By default, this is the first number field in each data frame. For example, you enter the following CSV content:
+In **Auto** series mapping mode, select which field or fields x represents. By default, this is the first number or time field in each data frame. For example, you enter the following CSV content:
 
 | a   | b   | c   |
 | --- | --- | --- |

packages/grafana-ui/src/components/uPlot/config/UPlotScaleBuilder.ts

@@ -8,6 +8,7 @@ import { PlotConfigBuilder } from '../types';
 export interface ScaleProps {
   scaleKey: string;
   isTime?: boolean;
+  auto?: boolean;
   min?: number | null;
   max?: number | null;
   softMin?: number | null;
@@ -32,6 +33,7 @@ export class UPlotScaleBuilder extends PlotConfigBuilder<ScaleProps, Scale> {
   getConfig(): Scale {
     let {
       isTime,
+      auto,
       scaleKey,
       min: hardMin,
       max: hardMax,
@@ -256,7 +258,7 @@ export class UPlotScaleBuilder extends PlotConfigBuilder<ScaleProps, Scale> {
       return minMax;
     };
 
-    let auto = !isTime && !hasFixedRange;
+    auto ??= !isTime && !hasFixedRange;
 
     if (isBooleanUnit(scaleKey)) {
       auto = false;

public/app/plugins/panel/xychart/SeriesEditor.tsx

@@ -182,10 +182,11 @@ export const SeriesEditor = ({
                   filter: (field) =>
                     (mapping === SeriesMapping.Auto ||
                       field.state?.origin?.frameIndex === series.frame?.matcher.options) &&
-                    field.type === FieldType.number &&
+                    (field.type === FieldType.number || field.type === FieldType.time) &&
                     !field.config.custom?.hideFrom?.viz,
                   baseNameMode,
-                  placeholderText: mapping === SeriesMapping.Auto ? 'First number field in each frame' : undefined,
+                  placeholderText:
+                    mapping === SeriesMapping.Auto ? 'First number or time field in each frame' : undefined,
                 },
               }}
             />

public/app/plugins/panel/xychart/scatter.ts

@@ -298,6 +298,7 @@ export const prepConfig = (xySeries: XYSeries[], theme: GrafanaTheme2) => {
   builder.setMode(2);
 
   let xField = xySeries[0].x.field;
+  let xIsTime = xField.type === FieldType.time;
 
   let fieldConfig = xField.config;
   let customConfig = fieldConfig.custom;
@@ -305,7 +306,8 @@ export const prepConfig = (xySeries: XYSeries[], theme: GrafanaTheme2) => {
 
   builder.addScale({
     scaleKey: 'x',
-    isTime: false,
+    isTime: xIsTime,
+    auto: true,
     orientation: ScaleOrientation.Horizontal,
     direction: ScaleDirection.Right,
     distribution: scaleDistr?.type,
@@ -317,6 +319,7 @@ export const prepConfig = (xySeries: XYSeries[], theme: GrafanaTheme2) => {
     softMax: customConfig?.axisSoftMax,
     centeredZero: customConfig?.axisCenteredZero,
     decimals: fieldConfig.decimals,
+    range: xIsTime ? (u, min, max) => [min, max] : undefined,
   });
 
   // why does this fall back to '' instead of null or undef?
@@ -339,13 +342,14 @@ export const prepConfig = (xySeries: XYSeries[], theme: GrafanaTheme2) => {
 
   builder.addAxis({
     scaleKey: 'x',
+    isTime: xIsTime,
     placement: customConfig?.axisPlacement !== AxisPlacement.Hidden ? AxisPlacement.Bottom : AxisPlacement.Hidden,
     show: customConfig?.axisPlacement !== AxisPlacement.Hidden,
     grid: { show: customConfig?.axisGridShow },
     border: { show: customConfig?.axisBorderShow },
     theme,
     label: xAxisLabel,
-    formatValue: (v, decimals) => formattedValueToString(xField.display!(v, decimals)),
+    formatValue: xIsTime ? undefined : (v, decimals) => formattedValueToString(xField.display!(v, decimals)),
   });
 
   xySeries.forEach((s, si) => {

public/app/plugins/panel/xychart/utils.ts

@@ -62,8 +62,8 @@ export function prepSeries(
 
     let xMatcher = getFieldMatcher(
       seriesCfg.x?.matcher ?? {
-        id: FieldMatcherID.byType,
-        options: 'number',
+        id: FieldMatcherID.byTypes,
+        options: new Set(['number', 'time']),
       }
     );
     let yMatcher = getFieldMatcher(
@@ -89,11 +89,16 @@ export function prepSeries(
 
       let frameSeries: XYSeries[] = [];
 
-      // only grabbing number fields (exclude time, string, enum, other)
-      let onlyNumFields = frame.fields.filter((field) => field.type === FieldType.number);
+      let onlyNumTimeFields = frame.fields.filter(
+        (field) => field.type === FieldType.number || field.type === FieldType.time
+      );
 
       // only one of these per frame
-      let x = onlyNumFields.find((field) => xMatcher(field, frame, frames));
+      let x = onlyNumTimeFields.find((field) => xMatcher(field, frame, frames));
+
+      // only grabbing number fields (exclude time, string, enum, other)
+      let onlyNumFields = onlyNumTimeFields.filter((field) => field.type === FieldType.number);
+
       let color =
         colorMatcher != null
           ? onlyNumFields.find((field) => field !== x && colorMatcher!(field, frame, frames))