1 files changed, 100 insertions, 0 deletions
diff --git a/src/pybind/mgr/dashboard/frontend/src/app/shared/services/prometheus-alert.service.ts b/src/pybind/mgr/dashboard/frontend/src/app/shared/services/prometheus-alert.service.ts
new file mode 100644
index 000000000..6223808fb
--- /dev/null
+++ b/src/pybind/mgr/dashboard/frontend/src/app/shared/services/prometheus-alert.service.ts
@@ -0,0 +1,100 @@
+import { Injectable } from '@angular/core';
+
+import _ from 'lodash';
+
+import { PrometheusService } from '../api/prometheus.service';
+import {
+  AlertmanagerAlert,
+  PrometheusCustomAlert,
+  PrometheusRule
+} from '../models/prometheus-alerts';
+import { PrometheusAlertFormatter } from './prometheus-alert-formatter';
+
+@Injectable({
+  providedIn: 'root'
+})
+export class PrometheusAlertService {
+  private canAlertsBeNotified = false;
+  alerts: AlertmanagerAlert[] = [];
+  rules: PrometheusRule[] = [];
+  activeAlerts: number;
+
+  constructor(
+    private alertFormatter: PrometheusAlertFormatter,
+    private prometheusService: PrometheusService
+  ) {}
+
+  getAlerts() {
+    this.prometheusService.ifAlertmanagerConfigured(() => {
+      this.prometheusService.getAlerts().subscribe(
+        (alerts) => this.handleAlerts(alerts),
+        (resp) => {
+          if ([404, 504].includes(resp.status)) {
+            this.prometheusService.disableAlertmanagerConfig();
+          }
+        }
+      );
+    });
+  }
+
+  getRules() {
+    this.prometheusService.ifPrometheusConfigured(() => {
+      this.prometheusService.getRules('alerting').subscribe((groups) => {
+        this.rules = groups['groups'].reduce((acc, group) => {
+          return acc.concat(
+            group.rules.map((rule) => {
+              rule.group = group.name;
+              return rule;
+            })
+          );
+        }, []);
+      });
+    });
+  }
+
+  refresh() {
+    this.getAlerts();
+    this.getRules();
+  }
+
+  private handleAlerts(alerts: AlertmanagerAlert[]) {
+    if (this.canAlertsBeNotified) {
+      this.notifyOnAlertChanges(alerts, this.alerts);
+    }
+    this.activeAlerts = _.reduce<AlertmanagerAlert, number>(
+      this.alerts,
+      (result, alert) => (alert.status.state === 'active' ? ++result : result),
+      0
+    );
+    this.alerts = alerts;
+    this.canAlertsBeNotified = true;
+  }
+
+  private notifyOnAlertChanges(alerts: AlertmanagerAlert[], oldAlerts: AlertmanagerAlert[]) {
+    const changedAlerts = this.getChangedAlerts(
+      this.alertFormatter.convertToCustomAlerts(alerts),
+      this.alertFormatter.convertToCustomAlerts(oldAlerts)
+    );
+    const suppressedFiltered = _.filter(changedAlerts, (alert) => {
+      return alert.status !== 'suppressed';
+    });
+    const notifications = suppressedFiltered.map((alert) =>
+      this.alertFormatter.convertAlertToNotification(alert)
+    );
+    this.alertFormatter.sendNotifications(notifications);
+  }
+
+  private getChangedAlerts(alerts: PrometheusCustomAlert[], oldAlerts: PrometheusCustomAlert[]) {
+    const updatedAndNew = _.differenceWith(alerts, oldAlerts, _.isEqual);
+    return updatedAndNew.concat(this.getVanishedAlerts(alerts, oldAlerts));
+  }
+
+  private getVanishedAlerts(alerts: PrometheusCustomAlert[], oldAlerts: PrometheusCustomAlert[]) {
+    return _.differenceWith(oldAlerts, alerts, (a, b) => a.fingerprint === b.fingerprint).map(
+      (alert) => {
+        alert.status = 'resolved';
+        return alert;
+      }
+    );
+  }
+}