Add async support to HttpClient

Issue-ID: POLICY-1625
Signed-off-by: Jim Hahn <jrh3@att.com>
Change-Id: I0123b98e89b734efd264dd62080bb23573a7a3e6

2 files changed, 94 insertions, 4 deletions

diff --git a/policy-endpoints/src/main/java/org/onap/policy/common/endpoints/http/client/HttpClient.java b/policy-endpoints/src/main/java/org/onap/policy/common/endpoints/http/client/HttpClient.java
index 2fe46fb3..ebed1d7e 100644
--- a/policy-endpoints/src/main/java/org/onap/policy/common/endpoints/http/client/HttpClient.java
+++ b/policy-endpoints/src/main/java/org/onap/policy/common/endpoints/http/client/HttpClient.java
@@ -2,7 +2,7 @@
  * ============LICENSE_START=======================================================
  * ONAP
  * ================================================================================
- * Copyright (C) 2017-2019 AT&T Intellectual Property. All rights reserved.
+ * Copyright (C) 2017-2020 AT&T Intellectual Property. All rights reserved.
  * ================================================================================
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -21,14 +21,16 @@
 package org.onap.policy.common.endpoints.http.client;
 
 import java.util.Map;
-
+import java.util.concurrent.Future;
 import javax.ws.rs.client.Entity;
+import javax.ws.rs.client.InvocationCallback;
 import javax.ws.rs.core.Response;
 
 import org.onap.policy.common.capabilities.Startable;
 
 /**
- * Http Client interface.
+ * Http Client interface. Supports both synchronous and asynchronous operations.
+ *
  */
 public interface HttpClient extends Startable {
 
@@ -48,6 +50,24 @@ public interface HttpClient extends Startable {
     Response get();
 
     /**
+     * Asynchronous GET request.
+     *
+     * @param callback callback to be invoked, asynchronously, when the request completes
+     * @param path context uri path.
+     *
+     * @return future that can be used to cancel the request or await the response
+     */
+    Future<Response> get(InvocationCallback<Response> callback, String path);
+
+    /**
+     * Asynchronous GET request.
+     *
+     * @param callback callback to be invoked, asynchronously, when the request completes
+     * @return future that can be used to cancel the request or await the response
+     */
+    Future<Response> get(InvocationCallback<Response> callback);
+
+    /**
      * PUT request.
      *
      * @param path context uri path
@@ -59,6 +79,19 @@ public interface HttpClient extends Startable {
     Response put(String path, Entity<?> entity, Map<String, Object> headers);
 
     /**
+     * Asynchronous PUT request.
+     *
+     * @param callback callback to be invoked, asynchronously, when the request completes
+     * @param path context uri path
+     * @param entity body
+     * @param headers headers
+     *
+     * @return future that can be used to cancel the request or await the response
+     */
+    Future<Response> put(InvocationCallback<Response> callback, String path, Entity<?> entity,
+                    Map<String, Object> headers);
+
+    /**
      * POST request.
      *
      * @param path context uri path
@@ -70,6 +103,19 @@ public interface HttpClient extends Startable {
     Response post(String path, Entity<?> entity, Map<String, Object> headers);
 
     /**
+     * Asynchronous POST request.
+     *
+     * @param callback callback to be invoked, asynchronously, when the request completes
+     * @param path context uri path
+     * @param entity body
+     * @param headers headers
+     *
+     * @return future that can be used to cancel the request or await the response
+     */
+    Future<Response> post(InvocationCallback<Response> callback, String path, Entity<?> entity,
+                    Map<String, Object> headers);
+
+    /**
      * DELETE request.
      *
      * @param path context uri path
@@ -80,6 +126,17 @@ public interface HttpClient extends Startable {
     Response delete(String path, Map<String, Object> headers);
 
     /**
+     * Asynchronous DELETE request.
+     *
+     * @param callback callback to be invoked, asynchronously, when the request completes
+     * @param path context uri path
+     * @param headers headers
+     *
+     * @return future that can be used to cancel the request or await the response
+     */
+    Future<Response> delete(InvocationCallback<Response> callback, String path, Map<String, Object> headers);
+
+    /**
      * Retrieve the body from the HTTP transaction.
      *
      * @param response response.
diff --git a/policy-endpoints/src/main/java/org/onap/policy/common/endpoints/http/client/internal/JerseyClient.java b/policy-endpoints/src/main/java/org/onap/policy/common/endpoints/http/client/internal/JerseyClient.java
index 8a717712..1a822ff2 100644
--- a/policy-endpoints/src/main/java/org/onap/policy/common/endpoints/http/client/internal/JerseyClient.java
+++ b/policy-endpoints/src/main/java/org/onap/policy/common/endpoints/http/client/internal/JerseyClient.java
@@ -2,7 +2,7 @@
  * ============LICENSE_START=======================================================
  * ONAP
  * ================================================================================
- * Copyright (C) 2017-2019 AT&T Intellectual Property. All rights reserved.
+ * Copyright (C) 2017-2020 AT&T Intellectual Property. All rights reserved.
  * Modifications Copyright (C) 2018 Samsung Electronics Co., Ltd.
  * Modifications Copyright (C) 2019 Nordix Foundation.
  * ================================================================================
@@ -28,11 +28,13 @@ import java.security.NoSuchAlgorithmException;
 import java.security.SecureRandom;
 import java.util.Map;
 import java.util.Map.Entry;
+import java.util.concurrent.Future;
 import javax.net.ssl.SSLContext;
 import javax.ws.rs.client.Client;
 import javax.ws.rs.client.ClientBuilder;
 import javax.ws.rs.client.Entity;
 import javax.ws.rs.client.Invocation.Builder;
+import javax.ws.rs.client.InvocationCallback;
 import javax.ws.rs.core.Response;
 import org.apache.commons.lang3.StringUtils;
 import org.glassfish.jersey.client.ClientProperties;
@@ -169,21 +171,52 @@ public class JerseyClient implements HttpClient {
     }
 
     @Override
+    public Future<Response> get(InvocationCallback<Response> callback, String path) {
+        if (!StringUtils.isBlank(path)) {
+            return this.client.target(this.baseUrl).path(path).request().async().get(callback);
+        } else {
+            return this.client.target(this.baseUrl).request().async().get(callback);
+        }
+    }
+
+    @Override
+    public Future<Response> get(InvocationCallback<Response> callback) {
+        return this.client.target(this.baseUrl).request().async().get(callback);
+    }
+
+    @Override
     public Response put(String path, Entity<?> entity, Map<String, Object> headers) {
         return getBuilder(path, headers).put(entity);
     }
 
     @Override
+    public Future<Response> put(InvocationCallback<Response> callback, String path, Entity<?> entity,
+                    Map<String, Object> headers) {
+        return getBuilder(path, headers).async().put(entity, callback);
+    }
+
+    @Override
     public Response post(String path, Entity<?> entity, Map<String, Object> headers) {
         return getBuilder(path, headers).post(entity);
     }
 
     @Override
+    public Future<Response> post(InvocationCallback<Response> callback, String path, Entity<?> entity,
+                    Map<String, Object> headers) {
+        return getBuilder(path, headers).async().post(entity, callback);
+    }
+
+    @Override
     public Response delete(String path, Map<String, Object> headers) {
         return getBuilder(path, headers).delete();
     }
 
     @Override
+    public Future<Response> delete(InvocationCallback<Response> callback, String path, Map<String, Object> headers) {
+        return getBuilder(path, headers).async().delete(callback);
+    }
+
+    @Override
     public boolean start() {
         return alive;
     }