Analyze API to return 400 for wrong custom analyzer

docs/changelog/121568.yaml

@@ -0,0 +1,6 @@
+pr: 121568
+summary: Analyze API to return 400 for wrong custom analyzer
+area: Analysis
+type: bug
+issues:
+ - 121443

modules/analysis-common/src/yamlRestTest/resources/rest-api-spec/test/indices.analyze/15_analyze.yml

@@ -59,3 +59,24 @@
     - match:  { detail.tokenizer.tokens.0.token: ABc }
     - match:  { detail.tokenfilters.0.name: lowercase }
     - match:  { detail.tokenfilters.0.tokens.0.token: abc }
+
+---
+"Custom analyzer is not buildable":
+  - requires:
+      cluster_features: [ "wrong_custom_analyzer_return_400" ]
+      reason: "Returning 400 for wrong custom analyzer was added in this version"
+
+  - do:
+      catch: bad_request
+      indices.analyze:
+        body:
+          text: the foxes jumping quickly
+          tokenizer:
+            standard
+          filter:
+            type: hunspell
+            locale: en_US
+
+  - match: { status: 400 }
+  - match: { error.type: illegal_argument_exception }
+  - match: { error.reason: "Can not build a custom analyzer" }

server/src/main/java/module-info.java

@@ -426,6 +426,7 @@
     provides org.elasticsearch.features.FeatureSpecification
         with
             org.elasticsearch.action.bulk.BulkFeatures,
+            org.elasticsearch.action.admin.ActionFeatures,
             org.elasticsearch.features.FeatureInfrastructureFeatures,
             org.elasticsearch.rest.action.admin.cluster.ClusterRerouteFeatures,
             org.elasticsearch.index.mapper.MapperFeatures,
@@ -476,4 +477,5 @@
     exports org.elasticsearch.monitor.metrics;
     exports org.elasticsearch.plugins.internal.rewriter to org.elasticsearch.inference;
     exports org.elasticsearch.lucene.util.automaton;
+    exports org.elasticsearch.action.admin;
 }

server/src/main/java/org/elasticsearch/action/admin/ActionFeatures.java

@@ -0,0 +1,30 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the "Elastic License
+ * 2.0", the "GNU Affero General Public License v3.0 only", and the "Server Side
+ * Public License v 1"; you may not use this file except in compliance with, at
+ * your election, the "Elastic License 2.0", the "GNU Affero General Public
+ * License v3.0 only", or the "Server Side Public License, v 1".
+ */
+
+package org.elasticsearch.action.admin;
+
+import org.elasticsearch.features.FeatureSpecification;
+import org.elasticsearch.features.NodeFeature;
+
+import java.util.Set;
+
+import static org.elasticsearch.action.admin.indices.analyze.TransportAnalyzeAction.WRONG_CUSTOM_ANALYZER_RETURN_400;
+
+public class ActionFeatures implements FeatureSpecification {
+
+    @Override
+    public Set<NodeFeature> getFeatures() {
+        return Set.of();
+    }
+
+    @Override
+    public Set<NodeFeature> getTestFeatures() {
+        return Set.of(WRONG_CUSTOM_ANALYZER_RETURN_400);
+    }
+}

server/src/main/java/org/elasticsearch/action/admin/indices/analyze/TransportAnalyzeAction.java

@@ -29,6 +29,7 @@
 import org.elasticsearch.common.io.stream.Writeable;
 import org.elasticsearch.common.settings.Settings;
 import org.elasticsearch.core.IOUtils;
+import org.elasticsearch.features.NodeFeature;
 import org.elasticsearch.index.IndexService;
 import org.elasticsearch.index.IndexService.IndexCreationContext;
 import org.elasticsearch.index.IndexSettings;
@@ -65,6 +66,8 @@
  */
 public class TransportAnalyzeAction extends TransportSingleShardAction<AnalyzeAction.Request, AnalyzeAction.Response> {
 
+    public static final NodeFeature WRONG_CUSTOM_ANALYZER_RETURN_400 = new NodeFeature("wrong_custom_analyzer_return_400");
+
     private final Settings settings;
     private final IndicesService indicesService;
 
@@ -144,6 +147,8 @@ public static AnalyzeAction.Response analyze(
             if (analyzer != null) {
                 return analyze(request, analyzer, maxTokenCount);
             }
+        } catch (IllegalStateException e) {
+            throw new IllegalArgumentException("Can not build a custom analyzer", e);
         }
 
         // Otherwise we use a built-in analyzer, which should not be closed

server/src/main/resources/META-INF/services/org.elasticsearch.features.FeatureSpecification

@@ -8,6 +8,7 @@
 #
 
 org.elasticsearch.action.bulk.BulkFeatures
+org.elasticsearch.action.admin.ActionFeatures
 org.elasticsearch.features.FeatureInfrastructureFeatures
 org.elasticsearch.rest.action.admin.cluster.ClusterRerouteFeatures
 org.elasticsearch.index.IndexFeatures