[Backport 2.x] Change httpclient to async (#1958)

ml-algorithms/build.gradle

@@ -63,12 +63,13 @@ dependencies {
         }
     }
 
-    implementation platform('software.amazon.awssdk:bom:2.21.15')
+    implementation platform('software.amazon.awssdk:bom:2.25.40')
     implementation 'software.amazon.awssdk:auth'
     implementation 'software.amazon.awssdk:apache-client'
     implementation 'com.amazonaws:aws-encryption-sdk-java:2.4.1'
     implementation 'com.jayway.jsonpath:json-path:2.9.0'
     implementation group: 'org.json', name: 'json', version: '20231013'
+    implementation group: 'software.amazon.awssdk', name: 'netty-nio-client', version: '2.25.40'
 }
 
 lombok {

ml-algorithms/src/main/java/org/opensearch/ml/engine/Predictable.java

@@ -7,9 +7,11 @@
 
 import java.util.Map;
 
+import org.opensearch.core.action.ActionListener;
 import org.opensearch.ml.common.MLModel;
 import org.opensearch.ml.common.input.MLInput;
 import org.opensearch.ml.common.output.MLOutput;
+import org.opensearch.ml.common.transport.MLTaskResponse;
 import org.opensearch.ml.engine.encryptor.Encryptor;
 
 /**
@@ -31,7 +33,13 @@ public interface Predictable {
      * @param mlInput input data
      * @return predicted results
      */
-    MLOutput predict(MLInput mlInput);
+    default MLOutput predict(MLInput mlInput) {
+        throw new IllegalStateException("Method is not implemented");
+    }
+
+    default void asyncPredict(MLInput mlInput, ActionListener<MLTaskResponse> actionListener) {
+        actionListener.onFailure(new IllegalStateException("Method is not implemented"));
+    }
 
     /**
      * Init model (load model into memory) with ML model content and params.

ml-algorithms/src/main/java/org/opensearch/ml/engine/algorithms/remote/AwsConnectorExecutor.java

@@ -5,54 +5,43 @@
 
 package org.opensearch.ml.engine.algorithms.remote;
 
-import static org.opensearch.ml.common.CommonValue.REMOTE_SERVICE_ERROR;
 import static org.opensearch.ml.common.connector.ConnectorProtocols.AWS_SIGV4;
-import static org.opensearch.ml.engine.algorithms.remote.ConnectorUtils.processOutput;
 import static software.amazon.awssdk.http.SdkHttpMethod.POST;
 
-import java.io.BufferedReader;
-import java.io.InputStreamReader;
-import java.net.URI;
-import java.nio.charset.StandardCharsets;
 import java.security.AccessController;
 import java.security.PrivilegedExceptionAction;
 import java.time.Duration;
 import java.util.List;
 import java.util.Map;
+import java.util.concurrent.CompletableFuture;
 
-import org.opensearch.OpenSearchStatusException;
 import org.opensearch.client.Client;
 import org.opensearch.common.util.TokenBucket;
-import org.opensearch.core.rest.RestStatus;
+import org.opensearch.core.action.ActionListener;
 import org.opensearch.ml.common.connector.AwsConnector;
 import org.opensearch.ml.common.connector.Connector;
 import org.opensearch.ml.common.exception.MLException;
 import org.opensearch.ml.common.input.MLInput;
 import org.opensearch.ml.common.model.MLGuard;
 import org.opensearch.ml.common.output.model.ModelTensors;
 import org.opensearch.ml.engine.annotation.ConnectorExecutor;
+import org.opensearch.ml.engine.httpclient.MLHttpClientFactory;
 import org.opensearch.script.ScriptService;
 
 import lombok.Getter;
 import lombok.Setter;
 import lombok.extern.log4j.Log4j2;
-import software.amazon.awssdk.core.internal.http.loader.DefaultSdkHttpClientBuilder;
-import software.amazon.awssdk.core.sync.RequestBody;
-import software.amazon.awssdk.http.AbortableInputStream;
-import software.amazon.awssdk.http.HttpExecuteRequest;
-import software.amazon.awssdk.http.HttpExecuteResponse;
-import software.amazon.awssdk.http.SdkHttpClient;
-import software.amazon.awssdk.http.SdkHttpConfigurationOption;
+import software.amazon.awssdk.core.internal.http.async.SimpleHttpContentPublisher;
 import software.amazon.awssdk.http.SdkHttpFullRequest;
-import software.amazon.awssdk.utils.AttributeMap;
+import software.amazon.awssdk.http.async.AsyncExecuteRequest;
+import software.amazon.awssdk.http.async.SdkAsyncHttpClient;
 
 @Log4j2
 @ConnectorExecutor(AWS_SIGV4)
 public class AwsConnectorExecutor extends AbstractConnectorExecutor {
 
     @Getter
     private AwsConnector connector;
-    private SdkHttpClient httpClient;
     @Setter
     @Getter
     private ScriptService scriptService;
@@ -69,103 +58,52 @@ public class AwsConnectorExecutor extends AbstractConnectorExecutor {
     @Getter
     private MLGuard mlGuard;
 
-    public AwsConnectorExecutor(Connector connector, SdkHttpClient httpClient) {
-        this.connector = (AwsConnector) connector;
-        this.httpClient = httpClient;
-    }
+    private SdkAsyncHttpClient httpClient;
 
     public AwsConnectorExecutor(Connector connector) {
         super.initialize(connector);
         this.connector = (AwsConnector) connector;
-        Duration connectionTimeout = Duration.ofMillis(super.getConnectorClientConfig().getConnectionTimeout());
-        Duration readTimeout = Duration.ofMillis(super.getConnectorClientConfig().getReadTimeout());
-        try (
-            AttributeMap attributeMap = AttributeMap
-                .builder()
-                .put(SdkHttpConfigurationOption.CONNECTION_TIMEOUT, connectionTimeout)
-                .put(SdkHttpConfigurationOption.READ_TIMEOUT, readTimeout)
-                .put(SdkHttpConfigurationOption.MAX_CONNECTIONS, super.getConnectorClientConfig().getMaxConnections())
-                .build()
-        ) {
-            log
-                .info(
-                    "Initializing aws connector http client with attributes: connectionTimeout={}, readTimeout={}, maxConnections={}",
-                    connectionTimeout,
-                    readTimeout,
-                    super.getConnectorClientConfig().getMaxConnections()
-                );
-            this.httpClient = new DefaultSdkHttpClientBuilder().buildWithDefaults(attributeMap);
-        } catch (RuntimeException e) {
-            log.error("Error initializing AWS connector HTTP client.", e);
-            throw e;
-        } catch (Throwable e) {
-            log.error("Error initializing AWS connector HTTP client.", e);
-            throw new MLException(e);
-        }
+        Duration connectionTimeout = Duration.ofSeconds(super.getConnectorClientConfig().getConnectionTimeout());
+        Duration readTimeout = Duration.ofSeconds(super.getConnectorClientConfig().getReadTimeout());
+        Integer maxConnection = super.getConnectorClientConfig().getMaxConnections();
+        this.httpClient = MLHttpClientFactory.getAsyncHttpClient(connectionTimeout, readTimeout, maxConnection);
     }
 
     @SuppressWarnings("removal")
     @Override
-    public void invokeRemoteModel(MLInput mlInput, Map<String, String> parameters, String payload, List<ModelTensors> tensorOutputs) {
+    public void invokeRemoteModel(
+        MLInput mlInput,
+        Map<String, String> parameters,
+        String payload,
+        Map<Integer, ModelTensors> tensorOutputs,
+        ExecutionContext countDownLatch,
+        ActionListener<List<ModelTensors>> actionListener
+    ) {
         try {
-            String endpoint = connector.getPredictEndpoint(parameters);
-            RequestBody requestBody = RequestBody.fromString(payload);
-
-            SdkHttpFullRequest.Builder builder = SdkHttpFullRequest
-                .builder()
-                .method(POST)
-                .uri(URI.create(endpoint))
-                .contentStreamProvider(requestBody.contentStreamProvider());
-            Map<String, String> headers = connector.getDecryptedHeaders();
-            if (headers != null) {
-                for (String key : headers.keySet()) {
-                    builder.putHeader(key, headers.get(key));
-                }
-            }
-            SdkHttpFullRequest request = builder.build();
-            HttpExecuteRequest executeRequest = HttpExecuteRequest
+            SdkHttpFullRequest request = ConnectorUtils.buildSdkRequest(connector, parameters, payload, POST);
+            AsyncExecuteRequest executeRequest = AsyncExecuteRequest
                 .builder()
                 .request(signRequest(request))
-                .contentStreamProvider(request.contentStreamProvider().orElse(null))
+                .requestContentPublisher(new SimpleHttpContentPublisher(request))
+                .responseHandler(
+                    new MLSdkAsyncHttpResponseHandler(
+                        countDownLatch,
+                        actionListener,
+                        parameters,
+                        tensorOutputs,
+                        connector,
+                        scriptService,
+                        mlGuard
+                    )
+                )
                 .build();
-
-            HttpExecuteResponse response = AccessController
-                .doPrivileged((PrivilegedExceptionAction<HttpExecuteResponse>) () -> httpClient.prepareRequest(executeRequest).call());
-            int statusCode = response.httpResponse().statusCode();
-
-            AbortableInputStream body = null;
-            if (response.responseBody().isPresent()) {
-                body = response.responseBody().get();
-            }
-
-            StringBuilder responseBuilder = new StringBuilder();
-            if (body != null) {
-                try (BufferedReader reader = new BufferedReader(new InputStreamReader(body, StandardCharsets.UTF_8))) {
-                    String line;
-                    while ((line = reader.readLine()) != null) {
-                        responseBuilder.append(line);
-                    }
-                }
-            } else {
-                throw new OpenSearchStatusException("No response from model", RestStatus.BAD_REQUEST);
-            }
-            String modelResponse = responseBuilder.toString();
-            if (getMlGuard() != null && !getMlGuard().validate(modelResponse, MLGuard.Type.OUTPUT)) {
-                throw new IllegalArgumentException("guardrails triggered for LLM output");
-            }
-            if (statusCode < 200 || statusCode >= 300) {
-                throw new OpenSearchStatusException(REMOTE_SERVICE_ERROR + modelResponse, RestStatus.fromCode(statusCode));
-            }
-
-            ModelTensors tensors = processOutput(modelResponse, connector, scriptService, parameters);
-            tensors.setStatusCode(statusCode);
-            tensorOutputs.add(tensors);
+            AccessController.doPrivileged((PrivilegedExceptionAction<CompletableFuture<Void>>) () -> httpClient.execute(executeRequest));
         } catch (RuntimeException exception) {
             log.error("Failed to execute predict in aws connector: " + exception.getMessage(), exception);
-            throw exception;
+            actionListener.onFailure(exception);
         } catch (Throwable e) {
             log.error("Failed to execute predict in aws connector", e);
-            throw new MLException("Fail to execute predict in aws connector", e);
+            actionListener.onFailure(new MLException("Fail to execute predict in aws connector", e));
         }
     }
 

ml-algorithms/src/main/java/org/opensearch/ml/engine/algorithms/remote/ConnectorUtils.java

@@ -15,6 +15,8 @@
 import static org.opensearch.ml.engine.utils.ScriptUtils.executePostProcessFunction;
 
 import java.io.IOException;
+import java.net.URI;
+import java.nio.charset.Charset;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
@@ -34,6 +36,7 @@
 import org.opensearch.ml.common.dataset.TextSimilarityInputDataSet;
 import org.opensearch.ml.common.dataset.remote.RemoteInferenceInputDataSet;
 import org.opensearch.ml.common.input.MLInput;
+import org.opensearch.ml.common.model.MLGuard;
 import org.opensearch.ml.common.output.model.ModelTensor;
 import org.opensearch.ml.common.output.model.ModelTensors;
 import org.opensearch.script.ScriptService;
@@ -46,7 +49,9 @@
 import software.amazon.awssdk.auth.credentials.AwsSessionCredentials;
 import software.amazon.awssdk.auth.signer.Aws4Signer;
 import software.amazon.awssdk.auth.signer.params.Aws4SignerParams;
+import software.amazon.awssdk.core.sync.RequestBody;
 import software.amazon.awssdk.http.SdkHttpFullRequest;
+import software.amazon.awssdk.http.SdkHttpMethod;
 import software.amazon.awssdk.regions.Region;
 
 @Log4j2
@@ -179,11 +184,15 @@ public static ModelTensors processOutput(
         String modelResponse,
         Connector connector,
         ScriptService scriptService,
-        Map<String, String> parameters
+        Map<String, String> parameters,
+        MLGuard mlGuard
     ) throws IOException {
         if (modelResponse == null) {
             throw new IllegalArgumentException("model response is null");
         }
+        if (mlGuard != null && !mlGuard.validate(modelResponse, MLGuard.Type.OUTPUT)) {
+            throw new IllegalArgumentException("guardrails triggered for LLM output");
+        }
         List<ModelTensor> modelTensors = new ArrayList<>();
         Optional<ConnectorAction> predictAction = connector.findPredictAction();
         if (predictAction.isEmpty()) {
@@ -252,4 +261,42 @@ public static SdkHttpFullRequest signRequest(
 
         return signer.sign(request, params);
     }
+
+    public static SdkHttpFullRequest buildSdkRequest(
+        Connector connector,
+        Map<String, String> parameters,
+        String payload,
+        SdkHttpMethod method
+    ) {
+        String charset = parameters.getOrDefault("charset", "UTF-8");
+        RequestBody requestBody;
+        if (payload != null) {
+            requestBody = RequestBody.fromString(payload, Charset.forName(charset));
+        } else {
+            requestBody = RequestBody.empty();
+        }
+        if (SdkHttpMethod.POST == method && 0 == requestBody.optionalContentLength().get()) {
+            log.error("Content length is 0. Aborting request to remote model");
+            throw new IllegalArgumentException("Content length is 0. Aborting request to remote model");
+        }
+        String endpoint = connector.getPredictEndpoint(parameters);
+        SdkHttpFullRequest.Builder builder = SdkHttpFullRequest
+            .builder()
+            .method(method)
+            .uri(URI.create(endpoint))
+            .contentStreamProvider(requestBody.contentStreamProvider());
+        Map<String, String> headers = connector.getDecryptedHeaders();
+        if (headers != null) {
+            for (String key : headers.keySet()) {
+                builder.putHeader(key, headers.get(key));
+            }
+        }
+        if (builder.matchingHeaders("Content-Type").isEmpty()) {
+            builder.putHeader("Content-Type", "application/json");
+        }
+        if (builder.matchingHeaders("Content-Length").isEmpty()) {
+            builder.putHeader("Content-Length", requestBody.optionalContentLength().get().toString());
+        }
+        return builder.build();
+    }
 }

ml-algorithms/src/main/java/org/opensearch/ml/engine/algorithms/remote/ExecutionContext.java

@@ -0,0 +1,32 @@
+/*
+ *
+ *  * Copyright OpenSearch Contributors
+ *  * SPDX-License-Identifier: Apache-2.0
+ *
+ */
+
+package org.opensearch.ml.engine.algorithms.remote;
+
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.atomic.AtomicReference;
+
+import lombok.AllArgsConstructor;
+import lombok.Data;
+
+/**
+ * This class encapsulates several parameters that are used in a split-batch request case.
+ * A batch request is that in neural-search side multiple fields are send in one request to ml-commons,
+ * but the remote model doesn't accept list of string inputs so in ml-commons the request needs split.
+ * sequence is used to identify the index of the split request.
+ * countDownLatch is used to wait for all the split requests to finish.
+ * exceptionHolder is used to hold any exception thrown in a split-batch request.
+ */
+@Data
+@AllArgsConstructor
+public class ExecutionContext {
+    // Should never be null
+    private int sequence;
+    private CountDownLatch countDownLatch;
+    // This is to hold any exception thrown in a split-batch request
+    private AtomicReference<Exception> exceptionHolder;
+}