DisplayProcessor: improve time field support (#20223)

packages/grafana-data/src/datetime/moment_wrapper.ts

 import { TimeZone } from '../types/time';
 /* tslint:disable:import-blacklist ban ban-types */
 import moment, { Moment, MomentInput, DurationInputArg1 } from 'moment';
-import { DEFAULT_DATE_TIME_FORMAT } from './formats';
 export interface DateTimeBuiltinFormat {
   __momentBuiltinFormatBrand: any;
 }
@@ -38,7 +37,6 @@ export type DurationUnit =
   | 'quarters'
   | 'Q';
 
-export type DateFormatter = (date: DateTimeInput, format?: string) => string;
 export interface DateTimeLocale {
   firstDayOfWeek: () => number;
 }
@@ -115,10 +113,3 @@ export const dateTimeForTimeZone = (
 
   return dateTime(input, formatInput);
 };
-
-export const getTimeZoneDateFormatter: (timezone?: TimeZone) => DateFormatter = timezone => (date, format) => {
-  date = isDateTime(date) ? date : dateTime(date);
-  format = format || DEFAULT_DATE_TIME_FORMAT;
-
-  return timezone === 'browser' ? dateTime(date).format(format) : toUtc(date).format(format);
-};

packages/grafana-data/src/field/displayProcessor.test.ts

 import { getDisplayProcessor, getColorFromThreshold } from './displayProcessor';
 import { DisplayProcessor, DisplayValue } from '../types/displayValue';
 import { ValueMapping, MappingType } from '../types/valueMapping';
+import { FieldType } from '../types';
 
 function assertSame(input: any, processors: DisplayProcessor[], match: DisplayValue) {
   processors.forEach(processor => {
@@ -192,3 +193,38 @@ describe('Format value', () => {
     expect(instance(value).text).toEqual('1.000 Mil');
   });
 });
+
+describe('Date display options', () => {
+  it('should format UTC dates', () => {
+    const processor = getDisplayProcessor({
+      type: FieldType.time,
+      isUtc: true,
+      config: {
+        unit: 'xyz', // ignore non-date formats
+      },
+    });
+    expect(processor(0).text).toEqual('1970-01-01 00:00:00');
+  });
+
+  it('should pick configured time format', () => {
+    const processor = getDisplayProcessor({
+      type: FieldType.time,
+      isUtc: true,
+      config: {
+        unit: 'dateTimeAsUS', // A configurable date format
+      },
+    });
+    expect(processor(0).text).toEqual('01/01/1970 12:00:00 am');
+  });
+
+  it('respect the configured date format', () => {
+    const processor = getDisplayProcessor({
+      type: FieldType.time,
+      isUtc: true,
+      config: {
+        dateDisplayFormat: 'YYYY',
+      },
+    });
+    expect(processor(0).text).toEqual('1970');
+  });
+});

packages/grafana-data/src/field/displayProcessor.ts

@@ -11,8 +11,8 @@ import { DisplayProcessor, DisplayValue, DecimalCount, DecimalInfo } from '../ty
 import { getValueFormat } from '../valueFormats/valueFormats';
 import { getMappedValue } from '../utils/valueMappings';
 import { Threshold } from '../types/threshold';
-import { getTimeZoneDateFormatter } from '../datetime/moment_wrapper';
-import { DEFAULT_DATE_TIME_FORMAT } from '../datetime';
+import { DateTime, DEFAULT_DATE_TIME_FORMAT, isDateTime, dateTime, toUtc } from '../datetime';
+import { KeyValue } from '../types';
 
 interface DisplayProcessorOptions {
   type?: FieldType;
@@ -23,22 +23,39 @@ interface DisplayProcessorOptions {
   theme?: GrafanaTheme; // Will pick 'dark' if not defined
 }
 
+// Reasonable units for time
+const timeFormats: KeyValue<boolean> = {
+  dateTimeAsIso: true,
+  dateTimeAsUS: true,
+  dateTimeFromNow: true,
+};
+
 export function getDisplayProcessor(options?: DisplayProcessorOptions): DisplayProcessor {
   if (options && !_.isEmpty(options)) {
-    if (options.type && options.type === FieldType.time) {
-      return (value: any) => {
-        let dateFormat = DEFAULT_DATE_TIME_FORMAT;
-        if (options.config && options.config.dateDisplayFormat) {
-          dateFormat = options.config.dateDisplayFormat;
+    const field = options.config ? options.config : {};
+
+    if (options.type === FieldType.time) {
+      if (field.unit && timeFormats[field.unit]) {
+        // Currently selected unit is valid for time fields
+      } else {
+        const dateFormat = field.dateDisplayFormat || DEFAULT_DATE_TIME_FORMAT;
+
+        // UTC or browser based timezone
+        let fmt = (date: DateTime) => date.format(dateFormat);
+        if (options.isUtc) {
+          fmt = (date: DateTime) => toUtc(date).format(dateFormat);
         }
-        const formatedDate = getTimeZoneDateFormatter(options.isUtc ? 'utc' : 'browser')(value, dateFormat);
-        return {
-          numeric: value,
-          text: formatedDate,
+
+        return (value: any) => {
+          const date: DateTime = isDateTime(value) ? value : dateTime(value);
+          return {
+            numeric: isNaN(value) ? date.valueOf() : value,
+            text: fmt(date),
+          };
         };
-      };
+      }
     }
-    const field = options.config ? options.config : {};
+
     const formatFunc = getValueFormat(field.unit || 'none');
 
     return (value: any) => {