[APM] Optimize services overview

x-pack/plugins/apm/common/projections/services.ts

@@ -16,25 +16,37 @@ import { rangeFilter } from '../utils/range_filter';
 
 export function getServicesProjection({
   setup,
+  noEvents,
 }: {
   setup: Setup & SetupTimeRange & SetupUIFilters;
+  noEvents?: boolean;
 }) {
   const { start, end, uiFiltersES, indices } = setup;
 
   return {
-    index: [
-      indices['apm_oss.metricsIndices'],
-      indices['apm_oss.errorIndices'],
-      indices['apm_oss.transactionIndices'],
-    ],
+    ...(noEvents
+      ? {}
+      : {
+          index: [
+            indices['apm_oss.metricsIndices'],
+            indices['apm_oss.errorIndices'],
+            indices['apm_oss.transactionIndices'],
+          ],
+        }),
     body: {
       size: 0,
       query: {
         bool: {
           filter: [
-            {
-              terms: { [PROCESSOR_EVENT]: ['transaction', 'error', 'metric'] },
-            },
+            ...(noEvents
+              ? []
+              : [
+                  {
+                    terms: {
+                      [PROCESSOR_EVENT]: ['transaction', 'error', 'metric'],
+                    },
+                  },
+                ]),
             { range: rangeFilter(start, end) },
             ...uiFiltersES,
           ],

x-pack/plugins/apm/common/utils/array_union_to_callable.ts

@@ -0,0 +1,14 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+import { ValuesType } from 'utility-types';
+
+// work around a TypeScript limitation described in https://stackoverflow.com/posts/49511416
+
+export const arrayUnionToCallable = <T extends any[]>(
+  array: T
+): Array<ValuesType<T>> => {
+  return array;
+};

x-pack/plugins/apm/common/utils/join_by_key/index.test.ts

@@ -0,0 +1,104 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+import { joinByKey } from './';
+
+describe('joinByKey', () => {
+  it('joins by a string key', () => {
+    const joined = joinByKey(
+      [
+        {
+          serviceName: 'opbeans-node',
+          avg: 10,
+        },
+        {
+          serviceName: 'opbeans-node',
+          count: 12,
+        },
+        {
+          serviceName: 'opbeans-java',
+          avg: 11,
+        },
+        {
+          serviceName: 'opbeans-java',
+          p95: 18,
+        },
+      ],
+      'serviceName'
+    );
+
+    expect(joined.length).toBe(2);
+
+    expect(joined).toEqual([
+      {
+        serviceName: 'opbeans-node',
+        avg: 10,
+        count: 12,
+      },
+      {
+        serviceName: 'opbeans-java',
+        avg: 11,
+        p95: 18,
+      },
+    ]);
+  });
+
+  it('joins by a record key', () => {
+    const joined = joinByKey(
+      [
+        {
+          key: {
+            serviceName: 'opbeans-node',
+            transactionName: '/api/opbeans-node',
+          },
+          avg: 10,
+        },
+        {
+          key: {
+            serviceName: 'opbeans-node',
+            transactionName: '/api/opbeans-node',
+          },
+          count: 12,
+        },
+        {
+          key: {
+            serviceName: 'opbeans-java',
+            transactionName: '/api/opbeans-java',
+          },
+          avg: 11,
+        },
+        {
+          key: {
+            serviceName: 'opbeans-java',
+            transactionName: '/api/opbeans-java',
+          },
+          p95: 18,
+        },
+      ],
+      'key'
+    );
+
+    expect(joined.length).toBe(2);
+
+    expect(joined).toEqual([
+      {
+        key: {
+          serviceName: 'opbeans-node',
+          transactionName: '/api/opbeans-node',
+        },
+        avg: 10,
+        count: 12,
+      },
+      {
+        key: {
+          serviceName: 'opbeans-java',
+          transactionName: '/api/opbeans-java',
+        },
+        avg: 11,
+        p95: 18,
+      },
+    ]);
+  });
+});

x-pack/plugins/apm/common/utils/join_by_key/index.ts

@@ -0,0 +1,48 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+import { UnionToIntersection, ValuesType } from 'utility-types';
+import { isEqual } from 'lodash';
+
+/**
+ * Joins a list of records by a given key. Key can be any type of value, from
+ * strings to plain objects, as long as it is present in all records. `isEqual`
+ * is used for comparing keys. 
+ * 
+ * UnionToIntersection is needed to get all keys of union types, see below for
+ * example.
+ * 
+ const agentNames = [{ serviceName: '', agentName: '' }];
+ const transactionRates = [{ serviceName: '', transactionsPerMinute: 1 }];
+ const flattened = joinByKey(
+  [...agentNames, ...transactionRates],
+  'serviceName'
+ );
+*/
+
+type JoinedReturnType<
+  T extends Record<string, any>,
+  U extends UnionToIntersection<T>,
+  V extends keyof T & keyof U
+> = Array<Partial<U> & Record<V, U[V]>>;
+
+export function joinByKey<
+  T extends Record<string, any>,
+  U extends UnionToIntersection<T>,
+  V extends keyof T & keyof U
+>(items: T[], key: V): JoinedReturnType<T, U, V> {
+  return items.reduce<JoinedReturnType<T, U, V>>((prev, current) => {
+    let item = prev.find((prevItem) => isEqual(prevItem[key], current[key]));
+
+    if (!item) {
+      item = { ...current } as ValuesType<JoinedReturnType<T, U, V>>;
+      prev.push(item);
+    } else {
+      Object.assign(item, current);
+    }
+
+    return prev;
+  }, []);
+}