rename and add more UTs

Signed-off-by: xinyual <xinyual@amazon.com>

Author: xinyual

plugin/src/main/java/org/opensearch/ml/action/models/DeleteModelTransportAction.java

@@ -21,8 +21,10 @@
 import java.util.Arrays;
 import java.util.Deque;
 import java.util.List;
+import java.util.Locale;
 import java.util.Map;
 import java.util.Objects;
+import java.util.concurrent.CopyOnWriteArrayList;
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.function.Function;
@@ -264,19 +266,9 @@ private void checkAgentBeforeDeleteModel(String modelId, ActionListener<Boolean>
             if (searchHits.length == 0) {
                 actionListener.onResponse(true);
             } else {
-                List<String> relatedAgents = new ArrayList<>();
-                for (SearchHit hit : searchHits) {
-                    relatedAgents.add(hit.getId());
-                }
-                actionListener
-                    .onFailure(
-                        new OpenSearchStatusException(
-                            searchHits.length
-                                + " agents are still using this model, please delete or update the agents first: "
-                                + Arrays.toString(relatedAgents.toArray(new String[0])),
-                            RestStatus.CONFLICT
-                        )
-                    );
+                String errorMessage = formatAgentErrorMessage(searchHits);
+
+                actionListener.onFailure(new OpenSearchStatusException(errorMessage, RestStatus.CONFLICT));
             }
 
         }, e -> {
@@ -305,9 +297,13 @@ private void checkIngestPipelineBeforeDeleteModel(String modelId, ActionListener
                 actionListener
                     .onFailure(
                         new OpenSearchStatusException(
-                            allDependentPipelineIds.size()
-                                + " ingest pipelines are still using this model, please delete or update the pipelines first: "
-                                + Arrays.toString(allDependentPipelineIds.toArray(new String[0])),
+                            String
+                                .format(
+                                    Locale.ROOT,
+                                    "%d ingest pipelines are still using this model, please delete or update the pipelines first: %s",
+                                    allDependentPipelineIds.size(),
+                                    Arrays.toString(allDependentPipelineIds.toArray(new String[0]))
+                                ),
                             RestStatus.CONFLICT
                         )
                     );
@@ -335,9 +331,13 @@ private void checkSearchPipelineBeforeDeleteModel(String modelId, ActionListener
                 actionListener
                     .onFailure(
                         new OpenSearchStatusException(
-                            allDependentPipelineIds.size()
-                                + " search pipelines are still using this model, please delete or update the pipelines first: "
-                                + Arrays.toString(allDependentPipelineIds.toArray(new String[0])),
+                            String
+                                .format(
+                                    Locale.ROOT,
+                                    "%d search pipelines are still using this model, please delete or update the pipelines first: %s",
+                                    allDependentPipelineIds.size(),
+                                    Arrays.toString(allDependentPipelineIds.toArray(new String[0]))
+                                ),
                             RestStatus.CONFLICT
                         )
                     );
@@ -353,24 +353,23 @@ private void checkSearchPipelineBeforeDeleteModel(String modelId, ActionListener
     private void checkDownstreamTaskBeforeDeleteModel(String modelId, Boolean isHidden, ActionListener<DeleteResponse> actionListener) {
         CountDownLatch countDownLatch = new CountDownLatch(3);
         AtomicBoolean noneBlocked = new AtomicBoolean(true);
-        List<String> errorMessages = new ArrayList<>();
+        CopyOnWriteArrayList<String> errorMessages = new CopyOnWriteArrayList<>();
         ActionListener<Boolean> countDownActionListener = ActionListener.wrap(b -> {
             countDownLatch.countDown();
             noneBlocked.compareAndSet(true, b);
             if (countDownLatch.getCount() == 0) {
                 if (noneBlocked.get()) {
                     deleteModel(modelId, isHidden, actionListener);
                 } else {
-                    actionListener.onFailure(new OpenSearchStatusException(String.join(",", errorMessages), RestStatus.CONFLICT));
+                    actionListener.onFailure(new OpenSearchStatusException(String.join(". ", errorMessages), RestStatus.CONFLICT));
                 }
             }
         }, e -> {
             countDownLatch.countDown();
             noneBlocked.compareAndSet(true, false);
-            // actionListener.onFailure(e);
             errorMessages.add(e.getMessage());
             if (countDownLatch.getCount() == 0) {
-                actionListener.onFailure(new OpenSearchStatusException(String.join(",", errorMessages), RestStatus.CONFLICT));
+                actionListener.onFailure(new OpenSearchStatusException(String.join(". ", errorMessages), RestStatus.CONFLICT));
             }
 
         });
@@ -487,19 +486,19 @@ private <T> List<String> findDependentPipelines(
         List<String> dependentPipelineConfigurations = new ArrayList<>();
         for (T pipelineConfiguration : pipelineConfigurations) {
             Map<String, Object> config = getConfigFunction.apply(pipelineConfiguration);
-            if (searchThroughConfig(config, candidateModelId, "")) {
+            if (searchThroughConfig(config, candidateModelId)) {
                 dependentPipelineConfigurations.add(getIdFunction.apply(pipelineConfiguration));
             }
         }
         return dependentPipelineConfigurations;
     }
 
-    // This method is to go through the pipeline configs and only when the key is model id and value is
-    // 1. String and equal to candidate id 2. A list of String containing candidate id We will return True. Otherwise False
-    private Boolean searchThroughConfig(Object searchCandidate, String candidateId, String targetModelKey) {
+    // This method is to go through the pipeline configs and he configuration is a map of string to objects.
+    // Objects can be a list or a map. we will search exhaustively through the configuration for any match of the candidateId.
+    private Boolean searchThroughConfig(Object searchCandidate, String candidateId) {
         // Use a stack to store the elements to be processed
         Deque<Pair<String, Object>> stack = new ArrayDeque<>();
-        stack.push(Pair.of(targetModelKey, searchCandidate));
+        stack.push(Pair.of("", searchCandidate));
 
         while (!stack.isEmpty()) {
             // Pop an item from the stack
@@ -531,6 +530,29 @@ private Boolean searchThroughConfig(Object searchCandidate, String candidateId,
         return false;
     }
 
+    private String formatAgentErrorMessage(SearchHit[] hits) {
+        boolean isHidden = false;
+        for (SearchHit hit : hits) {
+            Map<String, Object> sourceAsMap = hit.getSourceAsMap();
+            isHidden = isHidden || Boolean.parseBoolean((String) sourceAsMap.getOrDefault(IS_HIDDEN_FIELD, false));
+        }
+        if (isHidden) {
+            return String
+                .format(Locale.ROOT, "%d agents are still using this model, please delete or update the agents first", hits.length);
+        }
+        List<String> agentIds = new ArrayList<>();
+        for (SearchHit hit : hits) {
+            agentIds.add(hit.getId());
+        }
+        return String
+            .format(
+                Locale.ROOT,
+                "%d agents are still using this model, please delete or update the agents first: %s",
+                hits.length,
+                Arrays.toString(agentIds.toArray(new String[0]))
+            );
+    }
+
     // this method is only to stub static method.
     @VisibleForTesting
     boolean isSuperAdminUserWrapper(ClusterService clusterService, Client client) {