Cloudwatch: Move getNextRefIdChar util from app/core/utils to @grafana/data (#80471)

---------

Co-authored-by: Alex Khomenko <Clarity-89@users.noreply.github.com>

packages/grafana-data/src/index.ts

@@ -16,6 +16,7 @@ export * from './events';
 export * from './themes';
 export * from './monaco';
 export * from './geo/layer';
+export * from './query';
 export {
   type ValueMatcherOptions,
   type BasicValueMatcherOptions,

packages/grafana-data/src/query/index.ts

@@ -0,0 +1 @@
+export * from './refId';

packages/grafana-data/src/query/refId.test.ts

@@ -0,0 +1,35 @@
+import { DataQuery } from '@grafana/schema';
+
+import { getNextRefId } from '.';
+
+export interface TestQuery extends DataQuery {
+  name?: string;
+}
+
+function dataQueryHelper(ids: string[]): DataQuery[] {
+  return ids.map((letter) => {
+    return { refId: letter };
+  });
+}
+
+const singleDataQuery: DataQuery[] = dataQueryHelper('ABCDE'.split(''));
+const outOfOrderDataQuery: DataQuery[] = dataQueryHelper('ABD'.split(''));
+const singleExtendedDataQuery: DataQuery[] = dataQueryHelper('ABCDEFGHIJKLMNOPQRSTUVWXYZ'.split(''));
+
+describe('Get next refId char', () => {
+  it('should return next char', () => {
+    expect(getNextRefId(singleDataQuery)).toEqual('F');
+  });
+
+  it('should get first char', () => {
+    expect(getNextRefId([])).toEqual('A');
+  });
+
+  it('should get the first available character if a query has been deleted out of order', () => {
+    expect(getNextRefId(outOfOrderDataQuery)).toEqual('C');
+  });
+
+  it('should append a new char and start from AA when Z is reached', () => {
+    expect(getNextRefId(singleExtendedDataQuery)).toEqual('AA');
+  });
+});

packages/grafana-data/src/query/refId.ts

@@ -0,0 +1,23 @@
+import { DataQuery } from '@grafana/schema';
+
+/**
+ * Finds the next available refId for a query
+ */
+export const getNextRefId = (queries: DataQuery[]): string => {
+  for (let num = 0; ; num++) {
+    const refId = getRefId(num);
+    if (!queries.some((query) => query.refId === refId)) {
+      return refId;
+    }
+  }
+};
+
+function getRefId(num: number): string {
+  const letters = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ';
+
+  if (num < letters.length) {
+    return letters[num];
+  } else {
+    return getRefId(Math.floor(num / letters.length) - 1) + letters[num % letters.length];
+  }
+}

public/app/core/utils/query.ts

@@ -1,5 +1,6 @@
 import { DataQuery, DataSourceRef } from '@grafana/data';
 
+// @deprecated use the `getNextRefId` function from grafana/data instead
 export const getNextRefIdChar = (queries: DataQuery[]): string => {
   for (let num = 0; ; num++) {
     const refId = getRefId(num);

public/app/plugins/datasource/cloudwatch/migrations/dashboardMigrations.ts

@@ -2,8 +2,8 @@
 // Migrations applied by the DashboardMigrator are performed before the plugin is loaded.
 // DashboardMigrator migrations are tied to a certain minimum version of a dashboard which means they will only be ran once.
 
-import { DataQuery, AnnotationQuery } from '@grafana/data';
+import { AnnotationQuery, getNextRefId } from '@grafana/data';
-import { getNextRefIdChar } from 'app/core/utils/query';
+import { DataQuery } from '@grafana/schema';
 
 import { CloudWatchMetricsQuery, LegacyAnnotationQuery, MetricQueryType, MetricEditorMode } from '../types';
 
@@ -20,7 +20,7 @@ export function migrateMultipleStatsMetricsQuery(
     }
   }
   for (const newTarget of newQueries) {
-    newTarget.refId = getNextRefIdChar(panelQueries);
+    newTarget.refId = getNextRefId(panelQueries);
     delete newTarget.statistics;
     panelQueries.push(newTarget);
   }