Using enum string representation for serioalization.

Author: afoucret

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/inference/ResolvedInference.java

@@ -17,12 +17,12 @@
 public record ResolvedInference(String inferenceId, TaskType taskType) implements Writeable {
 
     public ResolvedInference(StreamInput in) throws IOException {
-        this(in.readString(), in.readEnum(TaskType.class));
+        this(in.readString(), TaskType.valueOf(in.readString()));
     }
 
     @Override
     public void writeTo(StreamOutput out) throws IOException {
         out.writeString(inferenceId);
-        out.writeEnum(taskType);
+        out.writeString(taskType.name());
     }
 }

x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/inference/ResolvedInferenceTests.java

@@ -0,0 +1,47 @@
+/*
+ * 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; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+
+package org.elasticsearch.xpack.esql.inference;
+
+import org.elasticsearch.TransportVersion;
+import org.elasticsearch.inference.TaskType;
+import org.elasticsearch.test.AbstractWireTestCase;
+import org.elasticsearch.test.ESTestCase;
+
+import java.io.IOException;
+
+public class ResolvedInferenceTests extends AbstractWireTestCase<ResolvedInference> {
+
+    @Override
+    protected ResolvedInference createTestInstance() {
+        return new ResolvedInference(randomIdentifier(), randomTaskType());
+    }
+
+    @Override
+    protected ResolvedInference mutateInstance(ResolvedInference instance) throws IOException {
+        if (randomBoolean()) {
+            return new ResolvedInference(randomValueOtherThan(instance.inferenceId(), ESTestCase::randomIdentifier), instance.taskType());
+        }
+
+        return new ResolvedInference(instance.inferenceId(), randomValueOtherThan(instance.taskType(), this::randomTaskType));
+    }
+
+    @Override
+    protected ResolvedInference copyInstance(ResolvedInference instance, TransportVersion version) throws IOException {
+        return copyInstance(
+            instance,
+            getNamedWriteableRegistry(),
+            (out, v) -> v.writeTo(out),
+            in -> new ResolvedInference(in),
+            version
+        );
+    }
+
+    private TaskType randomTaskType() {
+        return randomFrom(TaskType.values());
+    }
+  }