[Observability]Adding specific Return APIs for each plugin (#69257)

* Adding specific apis for each plugin

* adding metric hosts stat

* addressing PR comment

* addressing PR comments

* changing series to key/value

* exporting interfaces

* adding label to stat

* refactoring types

Co-authored-by: Elastic Machine <elasticmachine@users.noreply.github.com>

x-pack/plugins/observability/public/data_handler.ts

@@ -4,17 +4,36 @@
  * you may not use this file except in compliance with the Elastic License.
  */
 
-import { FetchData, HasData } from './typings/data_handler';
+import { ObservabilityFetchDataResponse, FetchDataResponse } from './typings/fetch_data_response';
 import { ObservabilityApp } from '../typings/common';
 
+interface FetchDataParams {
+  // The start timestamp in milliseconds of the queried time interval
+  startTime: string;
+  // The end timestamp in milliseconds of the queried time interval
+  endTime: string;
+  // The aggregation bucket size in milliseconds if applicable to the data source
+  bucketSize: string;
+}
+
+export type FetchData<T extends FetchDataResponse = FetchDataResponse> = (
+  fetchDataParams: FetchDataParams
+) => Promise<T>;
+export type HasData = () => Promise<boolean>;
+
 interface DataHandler {
   fetchData: FetchData;
   hasData: HasData;
 }
 
 const dataHandlers: Partial<Record<ObservabilityApp, DataHandler>> = {};
 
-export type RegisterDataHandler = (params: { appName: ObservabilityApp } & DataHandler) => void;
+export type RegisterDataHandler<T extends ObservabilityApp = ObservabilityApp> = (params: {
+  appName: T;
+  fetchData: FetchData<ObservabilityFetchDataResponse[T]>;
+  hasData: HasData;
+}) => void;
+
 export const registerDataHandler: RegisterDataHandler = ({ appName, fetchData, hasData }) => {
   dataHandlers[appName] = { fetchData, hasData };
 };

x-pack/plugins/observability/public/typings/fetch_data_response/index.d.ts

@@ -0,0 +1,86 @@
+/*
+ * 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.
+ */
+
+interface Percentage {
+  label: string;
+  pct: number;
+  color?: string;
+}
+interface Bytes {
+  label: string;
+  bytes: number;
+  color?: string;
+}
+interface Numeral {
+  label: string;
+  value: number;
+  color?: string;
+}
+
+export interface Coordinates {
+  x: number;
+  y?: number;
+}
+
+interface Series {
+  label: string;
+  coordinates: Coordinates[];
+  color?: string;
+}
+
+export interface FetchDataResponse {
+  title: string;
+  appLink: string;
+}
+
+export interface LogsFetchDataResponse extends FetchDataResponse {
+  stats: Record<string, Numeral>;
+  series: Record<string, Series>;
+}
+
+export interface MetricsFetchDataResponse extends FetchDataResponse {
+  stats: {
+    hosts: Numeral;
+    cpu: Percentage;
+    memory: Percentage;
+    disk: Percentage;
+    inboundTraffic: Bytes;
+    outboundTraffic: Bytes;
+  };
+  series: {
+    inboundTraffic: Series;
+    outboundTraffic: Series;
+  };
+}
+
+export interface UptimeFetchDataResponse extends FetchDataResponse {
+  stats: {
+    monitors: Numeral;
+    up: Numeral;
+    down: Numeral;
+  };
+  series: {
+    up: Series;
+    down: Series;
+  };
+}
+
+export interface ApmFetchDataResponse extends FetchDataResponse {
+  stats: {
+    services: Numeral;
+    transactions: Numeral;
+  };
+  series: {
+    transactions: Series;
+  };
+}
+
+export interface ObservabilityFetchDataResponse {
+  apm: ApmFetchDataResponse;
+  infra_metrics: MetricsFetchDataResponse;
+  infra_logs: LogsFetchDataResponse;
+  uptime: UptimeFetchDataResponse;
+}