Transforms: add sort by transformer (#30370)

docs/sources/panels/transformations/types-options.md

@@ -17,6 +17,7 @@ Grafana comes with the following transformations:
 - [Add field from calculation](#add-field-from-calculation)
 - [Labels to fields](#labels-to-fields)
 - [Concatenate fields](#concatenate-fields)
+- [Sort by](#sort-by)
 - [Group by](#group-by)
 - [Merge](#merge)
 - [Rename by regex](#rename-by-regex)
@@ -236,6 +237,14 @@ After merge:
 | 2020-07-07 11:34:20 | ServerA | 10    |            |
 | 2020-07-07 11:34:20 |         | 20    | EU         |
 
+## Sort by
+
+> **Note:** This transformation is available in Grafana 7.4+.
+
+This transformation will sort each frame by the configured field, When `reverse` is checked, the values will return in
+the opposite order.
+
+
 ## Group by
 
 > **Note:** This transformation is available in Grafana 7.2+.

packages/grafana-data/src/transformations/transformers.ts

@@ -13,6 +13,7 @@ import { renameFieldsTransformer } from './transformers/rename';
 import { labelsToFieldsTransformer } from './transformers/labelsToFields';
 import { ensureColumnsTransformer } from './transformers/ensureColumns';
 import { groupByTransformer } from './transformers/groupBy';
+import { sortByTransformer } from './transformers/sortBy';
 import { mergeTransformer } from './transformers/merge';
 import { renameByRegexTransformer } from './transformers/renameByRegex';
 import { filterByValueTransformer } from './transformers/filterByValue';
@@ -35,6 +36,7 @@ export const standardTransformers = {
   labelsToFieldsTransformer,
   ensureColumnsTransformer,
   groupByTransformer,
+  sortByTransformer,
   mergeTransformer,
   renameByRegexTransformer,
 };

packages/grafana-data/src/transformations/transformers/ids.ts

@@ -21,4 +21,5 @@ export enum DataTransformerID {
   noop = 'noop',
   ensureColumns = 'ensureColumns',
   groupBy = 'groupBy',
+  sortBy = 'sortBy',
 }

packages/grafana-data/src/transformations/transformers/sortBy.test.ts

+import { toDataFrame } from '../../dataframe/processDataFrame';
+import { sortByTransformer, SortByTransformerOptions } from './sortBy';
+import { mockTransformationsRegistry } from '../../utils/tests/mockTransformationsRegistry';
+import { transformDataFrame } from '../transformDataFrame';
+import { Field, FieldType } from '../../types';
+import { DataTransformerID } from './ids';
+import { DataTransformerConfig } from '@grafana/data';
+
+const testFrame = toDataFrame({
+  name: 'A',
+  fields: [
+    { name: 'time', type: FieldType.time, values: [10, 9, 8, 7, 6, 5] }, // desc
+    { name: 'text', type: FieldType.string, values: ['a', 'z', 'b', 'x', 'c'] },
+    { name: 'count', type: FieldType.string, values: [1, 2, 3, 4, 5] }, // asc
+  ],
+});
+
+describe('SortBy transformer', () => {
+  beforeAll(() => {
+    mockTransformationsRegistry([sortByTransformer]);
+  });
+
+  it('should not apply transformation if config is missing sort fields', async () => {
+    const cfg: DataTransformerConfig<SortByTransformerOptions> = {
+      id: DataTransformerID.sortBy,
+      options: {
+        sort: [], // nothing
+      },
+    };
+
+    await expect(transformDataFrame([cfg], [testFrame])).toEmitValuesWith(received => {
+      const result = received[0];
+      expect(result[0]).toBe(testFrame);
+    });
+  });
+
+  it('should sort time asc', async () => {
+    const cfg: DataTransformerConfig<SortByTransformerOptions> = {
+      id: DataTransformerID.sortBy,
+      options: {
+        sort: [
+          {
+            field: 'time',
+          },
+        ],
+      },
+    };
+
+    await expect(transformDataFrame([cfg], [testFrame])).toEmitValuesWith(received => {
+      expect(getFieldSnapshot(received[0][0].fields[0])).toMatchInlineSnapshot(`
+        Object {
+          "name": "time",
+          "values": Array [
+            5,
+            6,
+            7,
+            8,
+            9,
+            10,
+          ],
+        }
+      `);
+    });
+  });
+
+  it('should sort time (desc)', async () => {
+    const cfg: DataTransformerConfig<SortByTransformerOptions> = {
+      id: DataTransformerID.sortBy,
+      options: {
+        sort: [
+          {
+            field: 'time',
+            desc: true,
+          },
+        ],
+      },
+    };
+
+    await expect(transformDataFrame([cfg], [testFrame])).toEmitValuesWith(received => {
+      expect(getFieldSnapshot(received[0][0].fields[0])).toMatchInlineSnapshot(`
+        Object {
+          "name": "time",
+          "values": Array [
+            10,
+            9,
+            8,
+            7,
+            6,
+            5,
+          ],
+        }
+      `);
+    });
+  });
+});
+
+function getFieldSnapshot(f: Field): Object {
+  return { name: f.name, values: f.values.toArray() };
+}

packages/grafana-data/src/transformations/transformers/sortBy.ts

+import { map } from 'rxjs/operators';
+
+import { DataTransformerID } from './ids';
+import { DataTransformerInfo } from '../../types/transformations';
+import { DataFrame } from '../../types';
+import { getFieldDisplayName } from '../../field';
+import { sortDataFrame } from '../../dataframe';
+
+export interface SortByField {
+  field: string;
+  desc?: boolean;
+  index?: number;
+}
+
+export interface SortByTransformerOptions {
+  // NOTE: this structure supports an array, however only the first entry is used
+  // future versions may support multi-sort options
+  sort: SortByField[];
+}
+
+export const sortByTransformer: DataTransformerInfo<SortByTransformerOptions> = {
+  id: DataTransformerID.sortBy,
+  name: 'Sort by',
+  description: 'Sort fields in a frame',
+  defaultOptions: {
+    fields: {},
+  },
+
+  /**
+   * Return a modified copy of the series.  If the transform is not or should not
+   * be applied, just return the input series
+   */
+  operator: options => source =>
+    source.pipe(
+      map(data => {
+        if (!Array.isArray(data) || data.length === 0 || !options?.sort?.length) {
+          return data;
+        }
+        return sortDataFrames(data, options.sort);
+      })
+    ),
+};
+
+export function sortDataFrames(data: DataFrame[], sort: SortByField[]): DataFrame[] {
+  return data.map(frame => {
+    const s = attachFieldIndex(frame, sort);
+    if (s.length && s[0].index != null) {
+      return sortDataFrame(frame, s[0].index, s[0].desc);
+    }
+    return frame;
+  });
+}
+
+function attachFieldIndex(frame: DataFrame, sort: SortByField[]): SortByField[] {
+  return sort.map(s => {
+    if (s.index != null) {
+      // null or undefined
+      return s;
+    }
+    return {
+      ...s,
+      index: frame.fields.findIndex(f => s.field === getFieldDisplayName(f, frame)),
+    };
+  });
+}

public/app/core/components/TransformersUI/SortByTransformerEditor.tsx

+import React, { useCallback, useMemo } from 'react';
+import { DataTransformerID, standardTransformers, TransformerRegistyItem, TransformerUIProps } from '@grafana/data';
+import { getAllFieldNamesFromDataFrames } from './OrganizeFieldsTransformerEditor';
+import { InlineField, InlineSwitch, InlineFieldRow, Select } from '@grafana/ui';
+
+import { SortByField, SortByTransformerOptions } from '@grafana/data/src/transformations/transformers/sortBy';
+
+export const SortByTransformerEditor: React.FC<TransformerUIProps<SortByTransformerOptions>> = ({
+  input,
+  options,
+  onChange,
+}) => {
+  const fieldNames = useMemo(
+    () =>
+      getAllFieldNamesFromDataFrames(input).map(n => ({
+        value: n,
+        label: n,
+      })),
+    [input]
+  );
+
+  // Only supports single sort for now
+  const onSortChange = useCallback(
+    (idx: number, cfg: SortByField) => {
+      onChange({ ...options, sort: [cfg] });
+    },
+    [options]
+  );
+
+  const sorts = options.sort?.length ? options.sort : [{} as SortByField];
+
+  return (
+    <div>
+      {sorts.map((s, index) => {
+        return (
+          <InlineFieldRow key={`${s.field}/${index}`}>
+            <InlineField label="Field" labelWidth={10} grow={true}>
+              <Select
+                options={fieldNames}
+                value={fieldNames.find(v => v.value === s.field)}
+                placeholder="Select field"
+                onChange={v => {
+                  onSortChange(index, { ...s, field: v.value! });
+                }}
+              />
+            </InlineField>
+            <InlineField label="Reverse">
+              <InlineSwitch
+                value={!!s.desc}
+                onChange={() => {
+                  onSortChange(index, { ...s, desc: !!!s.desc });
+                }}
+              />
+            </InlineField>
+          </InlineFieldRow>
+        );
+      })}
+    </div>
+  );
+};
+
+export const sortByTransformRegistryItem: TransformerRegistyItem<SortByTransformerOptions> = {
+  id: DataTransformerID.sortBy,
+  editor: SortByTransformerEditor,
+  transformation: standardTransformers.sortByTransformer,
+  name: standardTransformers.sortByTransformer.name,
+  description: standardTransformers.sortByTransformer.description,
+};

public/app/core/utils/standardTransformers.ts

@@ -8,6 +8,7 @@ import { seriesToFieldsTransformerRegistryItem } from '../components/Transformer
 import { calculateFieldTransformRegistryItem } from '../components/TransformersUI/CalculateFieldTransformerEditor';
 import { labelsToFieldsTransformerRegistryItem } from '../components/TransformersUI/LabelsToFieldsTransformerEditor';
 import { groupByTransformRegistryItem } from '../components/TransformersUI/GroupByTransformerEditor';
+import { sortByTransformRegistryItem } from '../components/TransformersUI/SortByTransformerEditor';
 import { mergeTransformerRegistryItem } from '../components/TransformersUI/MergeTransformerEditor';
 import { seriesToRowsTransformerRegistryItem } from '../components/TransformersUI/SeriesToRowsTransformerEditor';
 import { concatenateTransformRegistryItem } from '../components/TransformersUI/ConcatenateTransformerEditor';
@@ -27,6 +28,7 @@ export const getStandardTransformers = (): Array<TransformerRegistyItem<any>> =>
     calculateFieldTransformRegistryItem,
     labelsToFieldsTransformerRegistryItem,
     groupByTransformRegistryItem,
+    sortByTransformRegistryItem,
     mergeTransformerRegistryItem,
   ];
 };