Merge pull request #275 from amosproj/274-backend-module-alert-overvi…

…ew-page-severity-counter-api

Endpoint for getting Alert Severities count

apps/backend/src/app/alerting/alerting.controller.ts

@@ -14,6 +14,7 @@ import {
   ApiNotFoundResponse,
   ApiOperation,
   ApiQuery,
+  ApiResponse,
   ApiTags,
 } from '@nestjs/swagger';
 import { AlertingService } from './alerting.service';
@@ -29,6 +30,7 @@ import { PaginationOptionsDto } from '../utils/pagination/PaginationOptionsDto';
 import { AlertFilterDto } from './dto/alertFilter.dto';
 import { AlertOrderOptionsDto } from './dto/alertOrderOptions.dto';
 import { PaginationDto } from '../utils/pagination/PaginationDto';
+import { AlertStatisticsDto } from './dto/alertStatistics.dto';
 
 @ApiTags('Alerting')
 @Controller('alerting')
@@ -37,6 +39,19 @@ export class AlertingController {
 
   constructor(private readonly alertingService: AlertingService) {}
 
+  @Get('statistics')
+  @ApiOperation({
+    summary: 'Returns the number of Info, Warning and Critical alerts.',
+  })
+  @ApiResponse({
+    status: 200,
+    description: 'The number of Info, Warning and Critical alerts.',
+    type: AlertStatisticsDto,
+  })
+  async getStatistics(): Promise<AlertStatisticsDto> {
+    return this.alertingService.getStatistics();
+  }
+
   @Post('type')
   @ApiOperation({ summary: 'Create a new alert type.' })
   @ApiConflictResponse({ description: 'Alert type already exists' })

apps/backend/src/app/alerting/alerting.service.ts

@@ -38,6 +38,7 @@ import { PaginationOptionsDto } from '../utils/pagination/PaginationOptionsDto';
 import { AlertOrderOptionsDto } from './dto/alertOrderOptions.dto';
 import { AlertFilterDto } from './dto/alertFilter.dto';
 import { PaginationService } from '../utils/pagination/paginationService';
+import { AlertStatisticsDto } from './dto/alertStatistics.dto';
 
 @Injectable()
 export class AlertingService extends PaginationService implements OnModuleInit {
@@ -99,6 +100,29 @@ export class AlertingService extends PaginationService implements OnModuleInit {
     }
   }
 
+  async getStatistics(): Promise<AlertStatisticsDto> {
+    const alertStatisticsDto: AlertStatisticsDto = {
+      infoAlerts: 0,
+      warningAlerts: 0,
+      criticalAlerts: 0,
+    };
+    for (const repo of this.alertRepositories) {
+      const infoAlerts = await repo.count({
+        where: { alertType: { severity: SeverityType.INFO } },
+      });
+      const warningAlerts = await repo.count({
+        where: { alertType: { severity: SeverityType.WARNING } },
+      });
+      const criticalAlerts = await repo.count({
+        where: { alertType: { severity: SeverityType.CRITICAL } },
+      });
+      alertStatisticsDto.infoAlerts += infoAlerts;
+      alertStatisticsDto.warningAlerts += warningAlerts;
+      alertStatisticsDto.criticalAlerts += criticalAlerts;
+    }
+    return alertStatisticsDto;
+  }
+
   async createAlertType(createAlertTypeDto: CreateAlertTypeDto) {
     const entity = await this.alertTypeRepository.findOneBy({
       name: createAlertTypeDto.name,

apps/backend/src/app/alerting/dto/alertStatistics.dto.ts

@@ -0,0 +1,12 @@
+import { ApiProperty } from '@nestjs/swagger';
+
+export class AlertStatisticsDto {
+  @ApiProperty({ description: 'Number of Info alerts', example: 0 })
+  infoAlerts!: number;
+
+  @ApiProperty({ description: 'Number of Warning alerts', example: 0 })
+  warningAlerts!: number;
+
+  @ApiProperty({ description: 'Number of Critical alerts', example: 0 })
+  criticalAlerts!: number;
+}