feat(xo-server-perf-alert): regroup items with missing stats in one email (#4413)

Fixes #5104

CHANGELOG.unreleased.md

@@ -11,7 +11,7 @@
 
 > Users must be able to say: “I had this issue, happy to know it's fixed”
 
-- [Audit] Fix integrity check feedback not displayed (PR [#5106](https://github.com/vatesfr/xen-orchestra/pull/5106))
+- [Perf alert] Regroup items with missing stats in one email [#3137](https://github.com/vatesfr/xen-orchestra/issues/3137) (PR [#4413](https://github.com/vatesfr/xen-orchestra/pull/4413))
 
 ### Packages to release
 
@@ -30,4 +30,5 @@
 >
 > In case of conflict, the highest (lowest in previous list) `$version` wins.
 
+- xo-server-perf-alert patch
 - xo-web minor

packages/xo-server-perf-alert/src/index.js

@@ -592,22 +592,11 @@ ${monitorBodies.join('\n')}`
     const monitors = this._getMonitors()
     for (const monitor of monitors) {
       const snapshot = await monitor.snapshot()
-      for (const entry of snapshot) {
-        raiseOrLowerAlarm(
-          `${monitor.alarmId}|${entry.uuid}|RRD`,
-          entry.value === undefined,
-          () => {
-            this._sendAlertEmail(
-              'Secondary Issue',
-              `
-## There was an issue when trying to check ${monitor.title}
-${entry.listItem}`
-            )
-          },
-          () => {}
-        )
 
+      const entriesWithMissingStats = []
+      for (const entry of snapshot) {
         if (entry.value === undefined) {
+          entriesWithMissingStats.push(entry)
           continue
         }
 
@@ -656,6 +645,23 @@ ${entry.listItem}
           lowerAlarm
         )
       }
+
+      raiseOrLowerAlarm(
+        `${monitor.alarmId}|${entriesWithMissingStats
+          .map(({ uuid }) => uuid)
+          .sort()
+          .join('|')}|RRD`,
+        entriesWithMissingStats.length !== 0,
+        () => {
+          this._sendAlertEmail(
+            'Secondary Issue',
+            `
+## There was an issue when trying to check ${monitor.title}
+${entriesWithMissingStats.map(({ listItem }) => listItem).join('\n')}`
+          )
+        },
+        () => {}
+      )
     }
   }