[web-app] feature: case insensitive search (#2007)

Co-authored-by: tomsun28 <tomsun28@outlook.com>

web-app/src/app/routes/alert/alert-setting/alert-setting.component.html

@@ -194,7 +194,7 @@
             required
             name="target"
             id="target"
-            [nzShowSearch]="true"
+            [nzShowSearch]="{ filter: caseInsensitiveFilter }"
             [nzPlaceHolder]="'alert.setting.target.place-holder' | i18n"
             [nzOptions]="appHierarchies"
             [(ngModel)]="cascadeValues"

web-app/src/app/routes/alert/alert-setting/alert-setting.component.ts

@@ -20,6 +20,7 @@
 import { Component, Inject, OnInit } from '@angular/core';
 import { I18NService } from '@core';
 import { ALAIN_I18N_TOKEN } from '@delon/theme';
+import { NzCascaderFilter } from 'ng-zorro-antd/cascader';
 import { ModalButtonOptions, NzModalService } from 'ng-zorro-antd/modal';
 import { NzNotificationService } from 'ng-zorro-antd/notification';
 import { NzTableQueryParams } from 'ng-zorro-antd/table';
@@ -396,6 +397,12 @@ export class AlertSettingComponent implements OnInit {
   currentMetrics: any[] = [];
   alertRules: any[] = [{}];
   isExpr = false;
+  caseInsensitiveFilter: NzCascaderFilter = (i, p) => {
+    return p.some(o => {
+      const label = o.label;
+      return !!label && label.toLowerCase().indexOf(i.toLowerCase()) !== -1;
+    });
+  };
   cascadeOnChange(values: string[]): void {
     if (values == null || values.length != 3) {
       return;