Fix the export metrics format

Summary: Fix the format of the export. Due to unknown reason the changes done in the D14933499 was [reverted back](https://our.intern.facebook.com/intern/diff/D14933499/?src_number=80619316) on the same diff. Thus this diff fixes the format of the metrics export

Reviewed By: passy

Differential Revision: D15239653

fbshipit-source-id: b9416f89e1b0022000d6201eb08ca1f456d5ed2e

src/index.js

@@ -17,6 +17,7 @@ export {
   callClient,
 } from './plugin.js';
 export type {PluginClient, Props} from './plugin.js';
+export type {MetricType} from './utils/exportMetrics.js';
 export {default as Client} from './Client.js';
 export {clipboard} from 'electron';
 export * from './fb-stubs/constants.js';

src/plugin.js

@@ -10,7 +10,7 @@ import type {App} from './App.js';
 import type {Logger} from './fb-interfaces/Logger.js';
 import type Client from './Client.js';
 import type {Store, MiddlewareAPI} from './reducers/index.js';
-
+import type {MetricType} from './utils/exportMetrics.js';
 import React from 'react';
 import type {Node} from 'react';
 import BaseDevice from './devices/BaseDevice.js';
@@ -83,9 +83,9 @@ export class FlipperBasePlugin<
     method: string,
     data: Object,
   ) => $Shape<PersistedState>;
-  static exportMetrics: ?(
+  static metricsReducer: ?(
     persistedState: PersistedState,
-  ) => Promise<Map<string, number | string>>;
+  ) => Promise<MetricType>;
   static exportPersistedState: ?(
     callClient: (string, ?Object) => Promise<Object>,
     persistedState: ?PersistedState,

src/plugins/network/index.js

@@ -5,7 +5,12 @@
  * @format
  */
 
-import type {TableHighlightedRows, TableRows, TableBodyRow} from 'flipper';
+import type {
+  TableHighlightedRows,
+  TableRows,
+  TableBodyRow,
+  MetricType,
+} from 'flipper';
 import {padStart} from 'lodash';
 
 import {
@@ -107,9 +112,9 @@ export default class extends FlipperPlugin<State, *, PersistedState> {
     responses: {},
   };
 
-  static exportMetrics = (
+  static metricsReducer = (
     persistedState: PersistedState,
-  ): Promise<Map<string, number | string>> => {
+  ): Promise<MetricType> => {
     const failures = Object.keys(persistedState.responses).reduce(function(
       previous,
       key,
@@ -117,7 +122,7 @@ export default class extends FlipperPlugin<State, *, PersistedState> {
       return previous + (persistedState.responses[key].status >= 400);
     },
     0);
-    return Promise.resolve(new Map([['NUMBER_NETWORK_FAILURES', failures]]));
+    return Promise.resolve({NUMBER_NETWORK_FAILURES: failures});
   };
 
   static persistedStateReducer = (

src/utils/exportMetrics.js

@@ -4,19 +4,19 @@
  * LICENSE file in the root directory of this source tree.
  * @format
  */
-import type {MiddlewareAPI} from '../reducers';
-import {serialize} from './serialization.js';
 import type {FlipperPlugin, FlipperDevicePlugin} from 'flipper';
+import {serialize} from './serialization';
+import type {MiddlewareAPI} from '../reducers';
 
-type MetricType = Map<string, Map<string, string | number>>;
-
-export type ExportMetricType = Map<string, MetricType>;
+export type MetricType = {[metricName: string]: number};
+type MetricPluginType = {[pluginID: string]: MetricType};
+export type ExportMetricType = {[clientID: string]: MetricPluginType};
 
 export default async function exportMetrics(
   store: MiddlewareAPI,
 ): Promise<string> {
   const state = store.getState();
-  let metrics: ExportMetricType = new Map();
+  const metrics: ExportMetricType = {};
   for (let key in state.pluginStates) {
     const pluginStateData = state.pluginStates[key];
     const arr = key.split('#');
@@ -32,20 +32,19 @@ export default async function exportMetrics(
     state.plugins.devicePlugins.forEach((val, key) => {
       pluginsMap.set(key, val);
     });
-    const exportMetrics1: ?(
+    const metricsReducer: ?(
       persistedState: any,
-    ) => Promise<Map<string, string | number>> = pluginsMap.get(pluginName)
-      ?.exportMetrics;
-    if (pluginsMap.has(pluginName) && exportMetrics1) {
-      const metricMap = await exportMetrics1(pluginStateData);
-      const pluginMap = new Map([[pluginName, metricMap]]);
-      if (!metrics.get(clientID)) {
-        metrics.set(clientID, pluginMap);
+    ) => Promise<MetricType> = pluginsMap.get(pluginName)?.metricsReducer;
+    if (pluginsMap.has(pluginName) && metricsReducer) {
+      const metricsObject = await metricsReducer(pluginStateData);
+      const pluginObject = {};
+      pluginObject[pluginName] = metricsObject;
+      if (!metrics[clientID]) {
+        metrics[clientID] = pluginObject;
         continue;
       }
-      const prevMetricMap = metrics.get(clientID);
-      // $FlowFixMe: prevMetricMap cannot be null, because clientID is added only when the pluingMetricMap is available
-      metrics.set(clientID, new Map([...prevMetricMap, ...pluginMap]));
+      const mergedMetrics = {...metrics[clientID], ...pluginObject};
+      metrics[clientID] = mergedMetrics;
     }
   }
   return Promise.resolve(serialize(metrics));