[web-app] 告警中心告警列表展示

web-app/src/app/service/alert.service.ts

@@ -0,0 +1,31 @@
+import { Injectable } from '@angular/core';
+import {HttpClient, HttpParams} from "@angular/common/http";
+import {Observable} from "rxjs";
+import {Message} from "../pojo/Message";
+import {Page} from "../pojo/Page";
+import {Alert} from "../pojo/Alert";
+
+const alerts_uri = '/alerts';
+
+@Injectable({
+  providedIn: 'root'
+})
+export class AlertService {
+
+  constructor(private http : HttpClient) { }
+
+  public getAlerts(pageIndex: number, pageSize: number) : Observable<Message<Page<Alert>>> {
+    pageIndex = pageIndex ? pageIndex : 0;
+    pageSize = pageSize ? pageSize : 8;
+    // 注意HttpParams是不可变对象 需要保存set后返回的对象为最新对象
+    let httpParams = new HttpParams();
+    httpParams = httpParams.appendAll({
+      'sort': 'id',
+      'order': 'desc',
+      'pageIndex': pageIndex,
+      'pageSize': pageSize
+    });
+    const options = { params: httpParams };
+    return this.http.get<Message<Page<Alert>>>(alerts_uri, options);
+  }
+}