fix(app): remove duplicate values for multinode cluster [EE-6386] (#10947)

app/react/kubernetes/applications/components/PlacementFormSection/PlacementFormSection.tsx

@@ -122,15 +122,24 @@ function useNodeLabels(): NodeLabels {
       }))
     ) || [];
 
-  // get unique node labels with each label's possible values
-  const uniqueLabels = new Set(nodeLabelPairs.map((pair) => pair.key));
-  //   create a NodeLabels object with each label's possible values
-  const nodesLabels = Array.from(uniqueLabels).reduce((acc, key) => {
-    acc[key] = nodeLabelPairs
-      .filter((pair) => pair.key === key)
-      .map((pair) => pair.value);
-    return acc;
-  }, {} as NodeLabels);
+  // create a NodeLabels object with each label key's possible values, without duplicate keys or values. e.g. { 'beta.kubernetes.io/arch': ['amd64', 'arm64'] }
+  // in multinode clusters, there can be multiple nodes with the same label key
+  const allNodesLabels = nodeLabelPairs.map((pair) => pair.key);
+  const uniqueNodesLabels = new Set(allNodesLabels);
+  const nodesLabels: NodeLabels = Array.from(uniqueNodesLabels).reduce(
+    (acc: NodeLabels, key) => {
+      // get all possible values for a given node label key
+      const allNodeValuesForKey = nodeLabelPairs
+        .filter((pair) => pair.key === key)
+        .map((pair) => pair.value);
+      // in multinode clusters, there can be duplicate values for a given key, so remove them
+      const uniqueValues = Array.from(new Set(allNodeValuesForKey));
+
+      acc[key] = uniqueValues;
+      return acc;
+    },
+    {} as NodeLabels
+  );
 
   return nodesLabels;
 }