[Inference API] Introduce Update API to change some aspects of existi…

…ng inference endpoints (elastic#114457)

docs/changelog/114457.yaml

@@ -0,0 +1,6 @@
+pr: 114457
+summary: "[Inference API] Introduce Update API to change some aspects of existing\
+  \ inference endpoints"
+area: Machine Learning
+type: enhancement
+issues: []

server/src/main/java/org/elasticsearch/inference/EmptySecretSettings.java

@@ -16,6 +16,7 @@
 import org.elasticsearch.xcontent.XContentBuilder;
 
 import java.io.IOException;
+import java.util.Map;
 
 /**
  * This class defines an empty secret settings object. This is useful for services that do not have any secret settings.
@@ -48,4 +49,9 @@ public TransportVersion getMinimalSupportedVersion() {
 
     @Override
     public void writeTo(StreamOutput out) throws IOException {}
+
+    @Override
+    public SecretSettings newSecretSettings(Map<String, Object> newSecrets) {
+        return INSTANCE;
+    }
 }

server/src/main/java/org/elasticsearch/inference/EmptyTaskSettings.java

@@ -16,6 +16,7 @@
 import org.elasticsearch.xcontent.XContentBuilder;
 
 import java.io.IOException;
+import java.util.Map;
 
 /**
  * This class defines an empty task settings object. This is useful for services that do not have any task settings.
@@ -53,4 +54,9 @@ public TransportVersion getMinimalSupportedVersion() {
 
     @Override
     public void writeTo(StreamOutput out) throws IOException {}
+
+    @Override
+    public TaskSettings updatedTaskSettings(Map<String, Object> newSettings) {
+        return INSTANCE;
+    }
 }

server/src/main/java/org/elasticsearch/inference/SecretSettings.java

@@ -12,6 +12,9 @@
 import org.elasticsearch.common.io.stream.VersionedNamedWriteable;
 import org.elasticsearch.xcontent.ToXContentObject;
 
+import java.util.Map;
+
 public interface SecretSettings extends ToXContentObject, VersionedNamedWriteable {
 
+    SecretSettings newSecretSettings(Map<String, Object> newSecrets);
 }

server/src/main/java/org/elasticsearch/inference/TaskSettings.java

@@ -12,6 +12,11 @@
 import org.elasticsearch.common.io.stream.VersionedNamedWriteable;
 import org.elasticsearch.xcontent.ToXContentObject;
 
+import java.util.Map;
+
 public interface TaskSettings extends ToXContentObject, VersionedNamedWriteable {
+
     boolean isEmpty();
+
+    TaskSettings updatedTaskSettings(Map<String, Object> newSettings);
 }

x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/inference/action/UpdateInferenceModelAction.java

@@ -0,0 +1,278 @@
+/*
+ * 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.core.inference.action;
+
+import org.elasticsearch.ElasticsearchStatusException;
+import org.elasticsearch.action.ActionRequestValidationException;
+import org.elasticsearch.action.ActionResponse;
+import org.elasticsearch.action.ActionType;
+import org.elasticsearch.action.support.master.AcknowledgedRequest;
+import org.elasticsearch.common.bytes.BytesReference;
+import org.elasticsearch.common.io.stream.StreamInput;
+import org.elasticsearch.common.io.stream.StreamOutput;
+import org.elasticsearch.common.xcontent.XContentHelper;
+import org.elasticsearch.core.Nullable;
+import org.elasticsearch.core.TimeValue;
+import org.elasticsearch.inference.ModelConfigurations;
+import org.elasticsearch.inference.TaskType;
+import org.elasticsearch.rest.RestStatus;
+import org.elasticsearch.xcontent.ToXContentObject;
+import org.elasticsearch.xcontent.XContentBuilder;
+import org.elasticsearch.xcontent.XContentType;
+import org.elasticsearch.xpack.core.ml.job.messages.Messages;
+import org.elasticsearch.xpack.core.ml.utils.MlStrings;
+
+import java.io.IOException;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Objects;
+
+import static org.elasticsearch.inference.ModelConfigurations.SERVICE_SETTINGS;
+import static org.elasticsearch.inference.ModelConfigurations.TASK_SETTINGS;
+
+public class UpdateInferenceModelAction extends ActionType<UpdateInferenceModelAction.Response> {
+
+    public static final UpdateInferenceModelAction INSTANCE = new UpdateInferenceModelAction();
+    public static final String NAME = "cluster:admin/xpack/inference/update";
+
+    public UpdateInferenceModelAction() {
+        super(NAME);
+    }
+
+    public record Settings(
+        @Nullable Map<String, Object> serviceSettings,
+        @Nullable Map<String, Object> taskSettings,
+        @Nullable TaskType taskType
+    ) {}
+
+    public static class Request extends AcknowledgedRequest<Request> {
+
+        private final String inferenceEntityId;
+        private final BytesReference content;
+        private final XContentType contentType;
+        private final TaskType taskType;
+        private Settings settings;
+
+        public Request(String inferenceEntityId, BytesReference content, XContentType contentType, TaskType taskType, TimeValue timeout) {
+            super(timeout, DEFAULT_ACK_TIMEOUT);
+            this.inferenceEntityId = inferenceEntityId;
+            this.content = content;
+            this.contentType = contentType;
+            this.taskType = taskType;
+        }
+
+        public Request(StreamInput in) throws IOException {
+            super(in);
+            this.inferenceEntityId = in.readString();
+            this.content = in.readBytesReference();
+            this.taskType = TaskType.fromStream(in);
+            this.contentType = in.readEnum(XContentType.class);
+        }
+
+        public String getInferenceEntityId() {
+            return inferenceEntityId;
+        }
+
+        public TaskType getTaskType() {
+            return taskType;
+        }
+
+        /**
+         * The body of the request.
+         * For in-cluster models, this is expected to contain some of the following:
+         * "number_of_allocations": `an integer`
+         *
+         * For third-party services, this is expected to contain:
+         *  "service_settings": {
+         *      "api_key": `a string` // service settings can only contain an api key
+         *  }
+         *  "task_settings": { a map of settings }
+         *
+         */
+        public BytesReference getContent() {
+            return content;
+        }
+
+        /**
+         * The body of the request as a map.
+         * The map is validated such that only allowed fields are present.
+         * If any fields in the body are not on the allow list, this function will throw an exception.
+         */
+        public Settings getContentAsSettings() {
+            if (settings == null) { // settings is deterministic on content, so we only need to compute it once
+                Map<String, Object> unvalidatedMap = XContentHelper.convertToMap(content, false, contentType).v2();
+                Map<String, Object> serviceSettings = new HashMap<>();
+                Map<String, Object> taskSettings = new HashMap<>();
+                TaskType taskType = null;
+
+                if (unvalidatedMap.isEmpty()) {
+                    throw new ElasticsearchStatusException("Request body is empty", RestStatus.BAD_REQUEST);
+                }
+
+                if (unvalidatedMap.containsKey("task_type")) {
+                    if (unvalidatedMap.get("task_type") instanceof String taskTypeString) {
+                        taskType = TaskType.fromStringOrStatusException(taskTypeString);
+                    } else {
+                        throw new ElasticsearchStatusException(
+                            "Failed to parse [task_type] in update request [{}]",
+                            RestStatus.INTERNAL_SERVER_ERROR,
+                            unvalidatedMap.toString()
+                        );
+                    }
+                    unvalidatedMap.remove("task_type");
+                }
+
+                if (unvalidatedMap.containsKey(SERVICE_SETTINGS)) {
+                    if (unvalidatedMap.get(SERVICE_SETTINGS) instanceof Map<?, ?> tempMap) {
+                        for (Map.Entry<?, ?> entry : (tempMap).entrySet()) {
+                            if (entry.getKey() instanceof String key && entry.getValue() instanceof Object value) {
+                                serviceSettings.put(key, value);
+                            } else {
+                                throw new ElasticsearchStatusException(
+                                    "Failed to parse update request [{}]",
+                                    RestStatus.INTERNAL_SERVER_ERROR,
+                                    unvalidatedMap.toString()
+                                );
+                            }
+                        }
+                        unvalidatedMap.remove(SERVICE_SETTINGS);
+                    } else {
+                        throw new ElasticsearchStatusException(
+                            "Unable to parse service settings in the request [{}]",
+                            RestStatus.BAD_REQUEST,
+                            unvalidatedMap.toString()
+                        );
+                    }
+                }
+
+                if (unvalidatedMap.containsKey(TASK_SETTINGS)) {
+                    if (unvalidatedMap.get(TASK_SETTINGS) instanceof Map<?, ?> tempMap) {
+                        for (Map.Entry<?, ?> entry : (tempMap).entrySet()) {
+                            if (entry.getKey() instanceof String key && entry.getValue() instanceof Object value) {
+                                taskSettings.put(key, value);
+                            } else {
+                                throw new ElasticsearchStatusException(
+                                    "Failed to parse update request [{}]",
+                                    RestStatus.INTERNAL_SERVER_ERROR,
+                                    unvalidatedMap.toString()
+                                );
+                            }
+                        }
+                        unvalidatedMap.remove(TASK_SETTINGS);
+                    } else {
+                        throw new ElasticsearchStatusException(
+                            "Unable to parse task settings in the request [{}]",
+                            RestStatus.BAD_REQUEST,
+                            unvalidatedMap.toString()
+                        );
+                    }
+                }
+
+                if (unvalidatedMap.isEmpty() == false) {
+                    throw new ElasticsearchStatusException(
+                        "Request contained fields which cannot be updated, remove these fields and try again [{}]",
+                        RestStatus.BAD_REQUEST,
+                        unvalidatedMap.toString()
+                    );
+                }
+
+                this.settings = new Settings(
+                    serviceSettings.isEmpty() == false ? Collections.unmodifiableMap(serviceSettings) : null,
+                    taskSettings.isEmpty() == false ? Collections.unmodifiableMap(taskSettings) : null,
+                    taskType
+                );
+            }
+            return this.settings;
+        }
+
+        public XContentType getContentType() {
+            return contentType;
+        }
+
+        @Override
+        public void writeTo(StreamOutput out) throws IOException {
+            super.writeTo(out);
+            out.writeString(inferenceEntityId);
+            taskType.writeTo(out);
+            out.writeBytesReference(content);
+            XContentHelper.writeTo(out, contentType);
+        }
+
+        @Override
+        public ActionRequestValidationException validate() {
+            ActionRequestValidationException validationException = new ActionRequestValidationException();
+            if (MlStrings.isValidId(this.inferenceEntityId) == false) {
+                validationException.addValidationError(Messages.getMessage(Messages.INVALID_ID, "inference_id", this.inferenceEntityId));
+            }
+
+            if (validationException.validationErrors().isEmpty() == false) {
+                return validationException;
+            } else {
+                return null;
+            }
+        }
+
+        @Override
+        public boolean equals(Object o) {
+            if (this == o) return true;
+            if (o == null || getClass() != o.getClass()) return false;
+            Request request = (Request) o;
+            return Objects.equals(inferenceEntityId, request.inferenceEntityId)
+                && Objects.equals(content, request.content)
+                && contentType == request.contentType
+                && taskType == request.taskType;
+        }
+
+        @Override
+        public int hashCode() {
+            return Objects.hash(inferenceEntityId, content, contentType, taskType);
+        }
+    }
+
+    public static class Response extends ActionResponse implements ToXContentObject {
+
+        private final ModelConfigurations model;
+
+        public Response(ModelConfigurations model) {
+            this.model = model;
+        }
+
+        public Response(StreamInput in) throws IOException {
+            super(in);
+            model = new ModelConfigurations(in);
+        }
+
+        public ModelConfigurations getModel() {
+            return model;
+        }
+
+        @Override
+        public void writeTo(StreamOutput out) throws IOException {
+            model.writeTo(out);
+        }
+
+        @Override
+        public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
+            return model.toFilteredXContent(builder, params);
+        }
+
+        @Override
+        public boolean equals(Object o) {
+            if (this == o) return true;
+            if (o == null || getClass() != o.getClass()) return false;
+            Response response = (Response) o;
+            return Objects.equals(model, response.model);
+        }
+
+        @Override
+        public int hashCode() {
+            return Objects.hash(model);
+        }
+    }
+}

x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/ml/job/messages/Messages.java

@@ -281,6 +281,9 @@ public final class Messages {
     public static final String FIELD_CANNOT_BE_NULL = "Field [{0}] cannot be null";
     public static final String MODEL_ID_MATCHES_EXISTING_MODEL_IDS_BUT_MUST_NOT =
         "Model IDs must be unique. Requested model ID [{}] matches existing model IDs but must not.";
+    public static final String MODEL_ID_DOES_NOT_MATCH_EXISTING_MODEL_IDS_BUT_MUST_FOR_IN_CLUSTER_SERVICE =
+        "Requested model ID [{}] does not have a matching trained model and thus cannot be updated.";
+    public static final String INFERENCE_ENTITY_NON_EXISTANT_NO_UPDATE = "The inference endpoint [{}] does not exist and cannot be updated";
 
     private Messages() {}
 

x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/ml/utils/ExceptionsHelper.java

@@ -93,6 +93,10 @@ public static ElasticsearchStatusException badRequestException(String msg, Objec
         return new ElasticsearchStatusException(msg, RestStatus.BAD_REQUEST, args);
     }
 
+    public static ElasticsearchStatusException entityNotFoundException(String msg, Object... args) {
+        return new ElasticsearchStatusException(msg, RestStatus.NOT_FOUND, args);
+    }
+
     public static ElasticsearchStatusException taskOperationFailureToStatusException(TaskOperationFailure failure) {
         return new ElasticsearchStatusException(failure.getCause().getMessage(), failure.getStatus(), failure.getCause());
     }

x-pack/plugin/inference/qa/inference-service-tests/src/javaRestTest/java/org/elasticsearch/xpack/inference/InferenceBaseRestTest.java

@@ -81,6 +81,21 @@ static String mockSparseServiceModelConfig(@Nullable TaskType taskTypeInBody) {
             """, taskType);
     }
 
+    static String updateConfig(@Nullable TaskType taskTypeInBody, String apiKey, int temperature) {
+        var taskType = taskTypeInBody == null ? "" : "\"task_type\": \"" + taskTypeInBody + "\",";
+        return Strings.format("""
+            {
+              %s
+              "service_settings": {
+                "api_key": "%s"
+              },
+              "task_settings": {
+                "temperature": %d
+              }
+            }
+            """, taskType, apiKey, temperature);
+    }
+
     static String mockCompletionServiceModelConfig(@Nullable TaskType taskTypeInBody) {
         var taskType = taskTypeInBody == null ? "" : "\"task_type\": \"" + taskTypeInBody + "\",";
         return Strings.format("""
@@ -196,6 +211,11 @@ protected Map<String, Object> putModel(String modelId, String modelConfig, TaskT
         return putRequest(endpoint, modelConfig);
     }
 
+    protected Map<String, Object> updateEndpoint(String inferenceID, String modelConfig, TaskType taskType) throws IOException {
+        String endpoint = Strings.format("_inference/%s/%s/_update", taskType, inferenceID);
+        return putRequest(endpoint, modelConfig);
+    }
+
     protected Map<String, Object> putPipeline(String pipelineId, String modelId) throws IOException {
         String endpoint = Strings.format("_ingest/pipeline/%s", pipelineId);
         String body = """