[Feature/agent_framework] Registers a single agent with multiple tools

build.gradle

@@ -144,6 +144,7 @@ dependencies {
     implementation "org.opensearch:common-utils:${common_utils_version}"
     implementation 'com.amazonaws:aws-encryption-sdk-java:2.4.1'
     implementation 'org.bouncycastle:bcprov-jdk18on:1.77'
+    implementation "com.google.code.gson:gson:2.10.1"
 
     configurations.all {
         resolutionStrategy {

src/main/java/org/opensearch/flowframework/common/CommonValue.java

@@ -162,5 +162,20 @@ private CommonValue() {}
     public static final String RESOURCE_ID_FIELD = "resource_id";
     /** The field name for the ResourceCreated's resource name */
     public static final String WORKFLOW_STEP_NAME = "workflow_step_name";
-
+    /** LLM Name for registering an agent */
+    public static final String LLM_FIELD = "llm";
+    /** The tools' field for an agent */
+    public static final String TOOLS_FIELD = "tools";
+    /** The memory field for an agent */
+    public static final String MEMORY_FIELD = "memory";
+    /** The app type field for an agent */
+    public static final String APP_TYPE_FIELD = "app_type";
+    /** The agent id of an agent */
+    public static final String AGENT_ID = "agent_id";
+    /** To include field for an agent response */
+    public static final String INCLUDE_OUTPUT_IN_AGENT_RESPONSE = "include_output_in_agent_response";
+    /** The created time field for an agent */
+    public static final String CREATED_TIME = "created_time";
+    /** The last updated time field for an agent */
+    public static final String LAST_UPDATED_TIME_FIELD = "last_updated_time";
 }

src/main/java/org/opensearch/flowframework/model/Template.java

@@ -229,12 +229,12 @@ public XContentBuilder toXContent(XContentBuilder builder, Params params) throws
         for (Entry<String, Workflow> e : workflows.entrySet()) {
             xContentBuilder.field(e.getKey(), e.getValue(), params);
         }
+        xContentBuilder.endObject();
 
         if (uiMetadata != null && !uiMetadata.isEmpty()) {
             xContentBuilder.field(UI_METADATA_FIELD, uiMetadata);
         }
 
-        xContentBuilder.endObject();
         if (user != null) {
             xContentBuilder.field(USER_FIELD, user);
         }

src/main/java/org/opensearch/flowframework/model/WorkflowNode.java

@@ -14,6 +14,7 @@
 import org.opensearch.flowframework.workflow.ProcessNode;
 import org.opensearch.flowframework.workflow.WorkflowData;
 import org.opensearch.flowframework.workflow.WorkflowStep;
+import org.opensearch.ml.common.agent.LLMSpec;
 
 import java.io.IOException;
 import java.util.ArrayList;
@@ -24,7 +25,10 @@
 import java.util.Objects;
 
 import static org.opensearch.core.xcontent.XContentParserUtils.ensureExpectedToken;
+import static org.opensearch.flowframework.common.CommonValue.LLM_FIELD;
+import static org.opensearch.flowframework.util.ParseUtils.buildLLMMap;
 import static org.opensearch.flowframework.util.ParseUtils.buildStringToStringMap;
+import static org.opensearch.flowframework.util.ParseUtils.parseLLM;
 import static org.opensearch.flowframework.util.ParseUtils.parseStringToStringMap;
 
 /**
@@ -34,7 +38,6 @@
  * and its inputs are used to populate the {@link WorkflowData} input.
  */
 public class WorkflowNode implements ToXContentObject {
-
     /** The template field name for node id */
     public static final String ID_FIELD = "id";
     /** The template field name for node type */
@@ -82,7 +85,7 @@ public XContentBuilder toXContent(XContentBuilder builder, Params params) throws
         xContentBuilder.startObject(USER_INPUTS_FIELD);
         for (Entry<String, Object> e : userInputs.entrySet()) {
             xContentBuilder.field(e.getKey());
-            if (e.getValue() instanceof String) {
+            if (e.getValue() instanceof String || e.getValue() instanceof Number) {
                 xContentBuilder.value(e.getValue());
             } else if (e.getValue() instanceof Map<?, ?>) {
                 buildStringToStringMap(xContentBuilder, (Map<?, ?>) e.getValue());
@@ -98,6 +101,12 @@ public XContentBuilder toXContent(XContentBuilder builder, Params params) throws
                     }
                 }
                 xContentBuilder.endArray();
+            } else if (e.getValue() instanceof LLMSpec) {
+                if (LLM_FIELD.equals(e.getKey())) {
+                    xContentBuilder.startObject();
+                    buildLLMMap(xContentBuilder, (LLMSpec) e.getValue());
+                    xContentBuilder.endObject();
+                }
             }
         }
         xContentBuilder.endObject();
@@ -141,7 +150,11 @@ public static WorkflowNode parse(XContentParser parser) throws IOException {
                                 userInputs.put(inputFieldName, parser.text());
                                 break;
                             case START_OBJECT:
-                                userInputs.put(inputFieldName, parseStringToStringMap(parser));
+                                if (LLM_FIELD.equals(inputFieldName)) {
+                                    userInputs.put(inputFieldName, parseLLM(parser));
+                                } else {
+                                    userInputs.put(inputFieldName, parseStringToStringMap(parser));
+                                }
                                 break;
                             case START_ARRAY:
                                 if (PROCESSORS_FIELD.equals(inputFieldName)) {
@@ -158,6 +171,22 @@ public static WorkflowNode parse(XContentParser parser) throws IOException {
                                     userInputs.put(inputFieldName, mapList.toArray(new Map[0]));
                                 }
                                 break;
+                            case VALUE_NUMBER:
+                                switch (parser.numberType()) {
+                                    case INT:
+                                        userInputs.put(inputFieldName, parser.intValue());
+                                        break;
+                                    case LONG:
+                                        userInputs.put(inputFieldName, parser.longValue());
+                                        break;
+                                    case FLOAT:
+                                        userInputs.put(inputFieldName, parser.floatValue());
+                                        break;
+                                    case DOUBLE:
+                                        userInputs.put(inputFieldName, parser.doubleValue());
+                                        break;
+                                }
+                                break;
                             default:
                                 throw new IOException("Unable to parse field [" + inputFieldName + "] in a node object.");
                         }

src/main/java/org/opensearch/flowframework/util/ParseUtils.java

@@ -8,6 +8,7 @@
  */
 package org.opensearch.flowframework.util;
 
+import com.google.gson.Gson;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.opensearch.client.Client;
@@ -21,21 +22,34 @@
 import org.opensearch.core.xcontent.NamedXContentRegistry;
 import org.opensearch.core.xcontent.XContentBuilder;
 import org.opensearch.core.xcontent.XContentParser;
+import org.opensearch.ml.common.agent.LLMSpec;
 
 import java.io.IOException;
+import java.security.AccessController;
+import java.security.PrivilegedActionException;
+import java.security.PrivilegedExceptionAction;
 import java.time.Instant;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.Map.Entry;
 
 import static org.opensearch.core.xcontent.XContentParserUtils.ensureExpectedToken;
+import static org.opensearch.flowframework.common.CommonValue.MODEL_ID;
+import static org.opensearch.flowframework.common.CommonValue.PARAMETERS_FIELD;
+import static org.opensearch.ml.common.utils.StringUtils.getParameterMap;
 
 /**
  * Utility methods for Template parsing
  */
 public class ParseUtils {
     private static final Logger logger = LogManager.getLogger(ParseUtils.class);
 
+    public static final Gson gson;
+
+    static {
+        gson = new Gson();
+    }
+
     private ParseUtils() {}
 
     /**
@@ -70,6 +84,21 @@ public static void buildStringToStringMap(XContentBuilder xContentBuilder, Map<?
         xContentBuilder.endObject();
     }
 
+    /**
+     * Builds an XContent object representing a LLMSpec.
+     *
+     * @param xContentBuilder An XContent builder whose position is at the start of the map object to build
+     * @param llm LLMSpec
+     * @throws IOException on a build failure
+     */
+    public static void buildLLMMap(XContentBuilder xContentBuilder, LLMSpec llm) throws IOException {
+        String modelId = llm.getModelId();
+        Map<String, String> parameters = llm.getParameters();
+        xContentBuilder.field(MODEL_ID, modelId);
+        xContentBuilder.field(PARAMETERS_FIELD);
+        buildStringToStringMap(xContentBuilder, parameters);
+    }
+
     /**
      * Parses an XContent object representing a map of String keys to String values.
      *
@@ -88,6 +117,37 @@ public static Map<String, String> parseStringToStringMap(XContentParser parser)
         return map;
     }
 
+    // TODO Figure out a way to use the parse method of LLMSpec of ml-commons
+    /**
+     * Parses an XContent object representing the object of LLMSpec
+     * @param parser An XContent parser whose position is at the start of the map object to parse
+     * @return instance of {@link org.opensearch.ml.common.agent.LLMSpec}
+     * @throws IOException parsing error
+     */
+    public static LLMSpec parseLLM(XContentParser parser) throws IOException {
+        String modelId = null;
+        Map<String, String> parameters = null;
+
+        ensureExpectedToken(XContentParser.Token.START_OBJECT, parser.currentToken(), parser);
+        while (parser.nextToken() != XContentParser.Token.END_OBJECT) {
+            String fieldName = parser.currentName();
+            parser.nextToken();
+
+            switch (fieldName) {
+                case MODEL_ID:
+                    modelId = parser.text();
+                    break;
+                case PARAMETERS_FIELD:
+                    parameters = getParameterMap(parser.map());
+                    break;
+                default:
+                    parser.skipChildren();
+                    break;
+            }
+        }
+        return LLMSpec.builder().modelId(modelId).parameters(parameters).build();
+    }
+
     /**
      * Parse content parser to {@link java.time.Instant}.
      *
@@ -116,6 +176,31 @@ public static User getUserContext(Client client) {
         return User.parse(userStr);
     }
 
+    /**
+     * Generates a parameter map required when the parameter is nested within an object
+     * @param parameterObjs parameters
+     * @return a parameters map of type String,String
+     */
+    public static Map<String, String> getParameterMap(Map<String, ?> parameterObjs) {
+        Map<String, String> parameters = new HashMap<>();
+        for (String key : parameterObjs.keySet()) {
+            Object value = parameterObjs.get(key);
+            try {
+                AccessController.doPrivileged((PrivilegedExceptionAction<Void>) () -> {
+                    if (value instanceof String) {
+                        parameters.put(key, (String) value);
+                    } else {
+                        parameters.put(key, gson.toJson(value));
+                    }
+                    return null;
+                });
+            } catch (PrivilegedActionException e) {
+                throw new RuntimeException(e);
+            }
+        }
+        return parameters;
+    }
+
     /**
      * Creates a XContentParser from a given Registry
      *
@@ -129,4 +214,18 @@ public static XContentParser createXContentParserFromRegistry(NamedXContentRegis
         return XContentHelper.createParser(xContentRegistry, LoggingDeprecationHandler.INSTANCE, bytesReference, XContentType.JSON);
     }
 
+    /**
+     * Generates a string to string Map
+     * @param map content map
+     * @param fieldName fieldName
+     * @return instance of the map
+     */
+    @SuppressWarnings("unchecked")
+    public static Map<String, String> getStringToStringMap(Object map, String fieldName) {
+        if (map instanceof Map) {
+            return (Map<String, String>) map;
+        }
+        throw new IllegalArgumentException("[" + fieldName + "] must be a key-value map.");
+    }
+
 }

src/main/java/org/opensearch/flowframework/workflow/CreateConnectorStep.java

@@ -49,6 +49,7 @@
 import static org.opensearch.flowframework.common.CommonValue.PROTOCOL_FIELD;
 import static org.opensearch.flowframework.common.CommonValue.VERSION_FIELD;
 import static org.opensearch.flowframework.common.CommonValue.WORKFLOW_STATE_INDEX;
+import static org.opensearch.flowframework.util.ParseUtils.getStringToStringMap;
 
 /**
  * Step to create a connector for a remote model
@@ -210,14 +211,6 @@ public String getName() {
         return NAME;
     }
 
-    @SuppressWarnings("unchecked")
-    private static Map<String, String> getStringToStringMap(Object map, String fieldName) {
-        if (map instanceof Map) {
-            return (Map<String, String>) map;
-        }
-        throw new IllegalArgumentException("[" + fieldName + "] must be a key-value map.");
-    }
-
     private static Map<String, String> getParameterMap(Object parameterMap) throws PrivilegedActionException {
         Map<String, String> parameters = new HashMap<>();
         for (Entry<String, String> entry : getStringToStringMap(parameterMap, PARAMETERS_FIELD).entrySet()) {

src/main/java/org/opensearch/flowframework/workflow/CreateIndexStep.java

@@ -35,8 +35,8 @@
 public class CreateIndexStep implements WorkflowStep {
 
     private static final Logger logger = LogManager.getLogger(CreateIndexStep.class);
-    private ClusterService clusterService;
-    private Client client;
+    private final ClusterService clusterService;
+    private final Client client;
 
     /** The name of this step, used as a key in the template and the {@link WorkflowStepFactory} */
     static final String NAME = "create_index";

src/main/java/org/opensearch/flowframework/workflow/DeployModelStep.java

@@ -30,7 +30,7 @@
 public class DeployModelStep implements WorkflowStep {
     private static final Logger logger = LogManager.getLogger(DeployModelStep.class);
 
-    private MachineLearningNodeClient mlClient;
+    private final MachineLearningNodeClient mlClient;
     static final String NAME = "deploy_model";
 
     /**

src/main/java/org/opensearch/flowframework/workflow/ModelGroupStep.java

@@ -40,7 +40,7 @@ public class ModelGroupStep implements WorkflowStep {
 
     private static final Logger logger = LogManager.getLogger(ModelGroupStep.class);
 
-    private MachineLearningNodeClient mlClient;
+    private final MachineLearningNodeClient mlClient;
 
     static final String NAME = "model_group";