1 files changed, 78 insertions, 0 deletions
diff --git a/src/pybind/mgr/dashboard/frontend/src/app/shared/services/prometheus-silence-matcher.service.ts b/src/pybind/mgr/dashboard/frontend/src/app/shared/services/prometheus-silence-matcher.service.ts
new file mode 100644
index 000000000..7aec6d1d3
--- /dev/null
+++ b/src/pybind/mgr/dashboard/frontend/src/app/shared/services/prometheus-silence-matcher.service.ts
@@ -0,0 +1,78 @@
+import { Injectable } from '@angular/core';
+
+import _ from 'lodash';
+
+import {
+  AlertmanagerSilenceMatcher,
+  AlertmanagerSilenceMatcherMatch
+} from '../models/alertmanager-silence';
+import { PrometheusRule } from '../models/prometheus-alerts';
+
+@Injectable({
+  providedIn: 'root'
+})
+export class PrometheusSilenceMatcherService {
+  private valueAttributePath = {
+    alertname: 'name',
+    instance: 'alerts.0.labels.instance',
+    job: 'alerts.0.labels.job',
+    severity: 'labels.severity'
+  };
+
+  singleMatch(
+    matcher: AlertmanagerSilenceMatcher,
+    rules: PrometheusRule[]
+  ): AlertmanagerSilenceMatcherMatch {
+    return this.multiMatch([matcher], rules);
+  }
+
+  multiMatch(
+    matchers: AlertmanagerSilenceMatcher[],
+    rules: PrometheusRule[]
+  ): AlertmanagerSilenceMatcherMatch {
+    if (matchers.some((matcher) => matcher.isRegex)) {
+      return undefined;
+    }
+    matchers.forEach((matcher) => {
+      rules = this.getMatchedRules(matcher, rules);
+    });
+    return this.describeMatch(rules);
+  }
+
+  private getMatchedRules(
+    matcher: AlertmanagerSilenceMatcher,
+    rules: PrometheusRule[]
+  ): PrometheusRule[] {
+    const attributePath = this.getAttributePath(matcher.name);
+    return rules.filter((r) => _.get(r, attributePath) === matcher.value);
+  }
+
+  private describeMatch(rules: PrometheusRule[]): AlertmanagerSilenceMatcherMatch {
+    let alerts = 0;
+    rules.forEach((r) => (alerts += r.alerts.length));
+    return {
+      status: this.getMatchText(rules.length, alerts),
+      cssClass: alerts ? 'has-success' : 'has-warning'
+    };
+  }
+
+  getAttributePath(name: string): string {
+    return this.valueAttributePath[name];
+  }
+
+  private getMatchText(rules: number, alerts: number): string {
+    const msg = {
+      noRule: $localize`Your matcher seems to match no currently defined rule or active alert.`,
+      noAlerts: $localize`no active alerts`,
+      alert: $localize`1 active alert`,
+      alerts: $localize`${alerts} active alerts`,
+      rule: $localize`Matches 1 rule`,
+      rules: $localize`Matches ${rules} rules`
+    };
+
+    const rule = rules > 1 ? msg.rules : msg.rule;
+    const alert = alerts ? (alerts > 1 ? msg.alerts : msg.alert) : msg.noAlerts;
+
+    return rules ? $localize`${rule} with ${alert}.` : msg.noRule;
+  }
+}