From 9da41140aa08fed89b452d978c600148056f0759 Mon Sep 17 00:00:00 2001
From: Konrad Lalik <konrad.lalik@grafana.com>
Date: Wed, 1 Jun 2022 15:38:23 +0200
Subject: [PATCH] Alerting: Fix external alertmanager duplication (#49980)

* Fix external alertmanager duplication

* Add tests
---
 .../hooks/useExternalAMSelector.test.ts       | 37 +++++++++++++++++++
 .../unified/hooks/useExternalAmSelector.ts    | 30 +++++++--------
 2 files changed, 50 insertions(+), 17 deletions(-)

diff --git a/public/app/features/alerting/unified/hooks/useExternalAMSelector.test.ts b/public/app/features/alerting/unified/hooks/useExternalAMSelector.test.ts
index bf613686bf1..2a30a8a757b 100644
--- a/public/app/features/alerting/unified/hooks/useExternalAMSelector.test.ts
+++ b/public/app/features/alerting/unified/hooks/useExternalAMSelector.test.ts
@@ -127,4 +127,41 @@ describe('useExternalAmSelector', () => {
       },
     ]);
   });
+
+  it('The number of alert managers should match config entries when there are multiple entries of the same url', () => {
+    useSelectorMock.mockImplementation((callback) => {
+      return callback(
+        createMockStoreState(
+          [
+            { url: 'same/url/to/am/api/v2/alerts' },
+            { url: 'same/url/to/am/api/v2/alerts' },
+            { url: 'same/url/to/am/api/v2/alerts' },
+          ],
+          [],
+          ['same/url/to/am', 'same/url/to/am', 'same/url/to/am']
+        )
+      );
+    });
+
+    const alertmanagers = useExternalAmSelector();
+
+    expect(alertmanagers.length).toBe(3);
+    expect(alertmanagers).toEqual([
+      {
+        url: 'same/url/to/am',
+        actualUrl: 'same/url/to/am/api/v2/alerts',
+        status: 'active',
+      },
+      {
+        url: 'same/url/to/am',
+        actualUrl: 'same/url/to/am/api/v2/alerts',
+        status: 'active',
+      },
+      {
+        url: 'same/url/to/am',
+        actualUrl: 'same/url/to/am/api/v2/alerts',
+        status: 'active',
+      },
+    ]);
+  });
 });
diff --git a/public/app/features/alerting/unified/hooks/useExternalAmSelector.ts b/public/app/features/alerting/unified/hooks/useExternalAmSelector.ts
index 0a87417fefc..51a58075a13 100644
--- a/public/app/features/alerting/unified/hooks/useExternalAmSelector.ts
+++ b/public/app/features/alerting/unified/hooks/useExternalAmSelector.ts
@@ -18,7 +18,7 @@ export function useExternalAmSelector(): AlertmanagerConfig[] | [] {
   }
 
   const enabledAlertmanagers: AlertmanagerConfig[] = [];
-  const droppedAlertmanagers: AlertmanagerConfig[] = discoveredAlertmanagers?.droppedAlertManagers.map((am) => ({
+  const droppedAlertmanagers: AlertmanagerConfig[] = discoveredAlertmanagers.droppedAlertManagers.map((am) => ({
     url: am.url.replace(SUFFIX_REGEX, ''),
     status: 'dropped',
     actualUrl: am.url,
@@ -32,24 +32,20 @@ export function useExternalAmSelector(): AlertmanagerConfig[] | [] {
         actualUrl: '',
       });
     } else {
-      let found = false;
-      for (const activeAM of discoveredAlertmanagers.activeAlertManagers) {
-        if (activeAM.url === `${url}/api/v2/alerts`) {
-          found = true;
-          enabledAlertmanagers.push({
-            url: activeAM.url.replace(SUFFIX_REGEX, ''),
+      const matchingActiveAM = discoveredAlertmanagers.activeAlertManagers.find(
+        (am) => am.url === `${url}/api/v2/alerts`
+      );
+      matchingActiveAM
+        ? enabledAlertmanagers.push({
+            url: matchingActiveAM.url.replace(SUFFIX_REGEX, ''),
             status: 'active',
-            actualUrl: activeAM.url,
+            actualUrl: matchingActiveAM.url,
+          })
+        : enabledAlertmanagers.push({
+            url: url,
+            status: 'pending',
+            actualUrl: '',
           });
-        }
-      }
-      if (!found) {
-        enabledAlertmanagers.push({
-          url: url,
-          status: 'pending',
-          actualUrl: '',
-        });
-      }
     }
   }