Add async support to HttpClient

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

3 files changed, 236 insertions, 8 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;
     }
diff --git a/policy-endpoints/src/test/java/org/onap/policy/common/endpoints/http/server/test/HttpClientTest.java b/policy-endpoints/src/test/java/org/onap/policy/common/endpoints/http/server/test/HttpClientTest.java
index 2aaf1367..d3f94cd0 100644
--- a/policy-endpoints/src/test/java/org/onap/policy/common/endpoints/http/server/test/HttpClientTest.java
+++ b/policy-endpoints/src/test/java/org/onap/policy/common/endpoints/http/server/test/HttpClientTest.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.
  * ================================================================================
  * Licensed under the Apache License, Version 2.0 (the "License");
@@ -23,15 +23,21 @@ package org.onap.policy.common.endpoints.http.server.test;
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertSame;
 import static org.junit.Assert.assertTrue;
 
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Properties;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.TimeUnit;
 import javax.ws.rs.client.Entity;
+import javax.ws.rs.client.InvocationCallback;
 import javax.ws.rs.core.MediaType;
 import javax.ws.rs.core.Response;
+import lombok.Getter;
 import org.junit.AfterClass;
 import org.junit.Before;
 import org.junit.BeforeClass;
@@ -194,6 +200,28 @@ public class HttpClientTest {
     }
 
     @Test
+    public void testHttpGetNoAuthClientAsync() throws Exception {
+        final HttpClient client = getNoAuthHttpClient(TEST_HTTP_NO_AUTH_CLIENT, false,
+            6666);
+        MyCallback callback = new MyCallback();
+        final Response response = client.get(callback, HELLO).get();
+
+        verifyCallback("testHttpGetNoAuthClientAsync", callback, response);
+
+        final String body = HttpClient.getBody(response, String.class);
+
+        assertEquals(200, response.getStatus());
+        assertEquals(HELLO, body);
+    }
+
+    private void verifyCallback(String testName, MyCallback callback, final Response response)
+                    throws InterruptedException {
+        assertTrue(testName, callback.await());
+        assertNull(testName, callback.getThrowable());
+        assertSame(testName, response, callback.getResponse());
+    }
+
+    @Test
     public void testHttpPutNoAuthClient() throws Exception {
         final HttpClient client = getNoAuthHttpClient(TEST_HTTP_NO_AUTH_CLIENT, false, 6666);
 
@@ -206,6 +234,22 @@ public class HttpClientTest {
     }
 
     @Test
+    public void testHttpPutNoAuthClientAsync() throws Exception {
+        final HttpClient client = getNoAuthHttpClient(TEST_HTTP_NO_AUTH_CLIENT, false, 6666);
+
+        Entity<MyEntity> entity = Entity.entity(new MyEntity(MY_VALUE), MediaType.APPLICATION_JSON);
+        MyCallback callback = new MyCallback();
+        final Response response = client.put(callback, HELLO, entity, Collections.emptyMap()).get();
+
+        verifyCallback("testHttpPutNoAuthClientAsync", callback, response);
+
+        final String body = HttpClient.getBody(response, String.class);
+
+        assertEquals(200, response.getStatus());
+        assertEquals(PUT_HELLO, body);
+    }
+
+    @Test
     public void testHttpPostNoAuthClient() throws Exception {
         final HttpClient client = getNoAuthHttpClient(TEST_HTTP_NO_AUTH_CLIENT, false,
             6666);
@@ -219,6 +263,23 @@ public class HttpClientTest {
     }
 
     @Test
+    public void testHttpPostNoAuthClientAsync() throws Exception {
+        final HttpClient client = getNoAuthHttpClient(TEST_HTTP_NO_AUTH_CLIENT, false,
+            6666);
+
+        Entity<MyEntity> entity = Entity.entity(new MyEntity(MY_VALUE), MediaType.APPLICATION_JSON);
+        MyCallback callback = new MyCallback();
+        final Response response = client.post(callback, HELLO, entity, Collections.emptyMap()).get();
+
+        verifyCallback("testHttpPostNoAuthClientAsync", callback, response);
+
+        final String body = HttpClient.getBody(response, String.class);
+
+        assertEquals(200, response.getStatus());
+        assertEquals("POST:hello:{myParameter=myValue}", body);
+    }
+
+    @Test
     public void testHttpDeletetNoAuthClient() throws Exception {
         final HttpClient client = getNoAuthHttpClient(TEST_HTTP_NO_AUTH_CLIENT, false,
             6666);
@@ -231,6 +292,41 @@ public class HttpClientTest {
     }
 
     @Test
+    public void testHttpDeletetNoAuthClientAsync() throws Exception {
+        final HttpClient client = getNoAuthHttpClient(TEST_HTTP_NO_AUTH_CLIENT, false,
+            6666);
+
+        MyCallback callback = new MyCallback();
+        final Response response = client.delete(callback, HELLO, Collections.emptyMap()).get();
+
+        verifyCallback("testHttpDeletetNoAuthClientAsync", callback, response);
+
+        final String body = HttpClient.getBody(response, String.class);
+
+        assertEquals(200, response.getStatus());
+        assertEquals("DELETE:hello", body);
+    }
+
+    /**
+     * Perform one asynchronous test with auth client; don't need to test every method.
+     * @throws Exception if an error occurs
+     */
+    @Test
+    public void testHttpAsyncAuthClient() throws Exception {
+        final HttpClient client = getAuthHttpClient();
+
+        MyCallback callback = new MyCallback();
+        final Response response = client.get(callback, HELLO).get();
+
+        verifyCallback("testHttpAsyncAuthClient", callback, response);
+
+        final String body = HttpClient.getBody(response, String.class);
+
+        assertEquals(200, response.getStatus());
+        assertEquals(HELLO, body);
+    }
+
+    @Test
     public void testHttpGetAuthClient() throws Exception {
         final HttpClient client = getAuthHttpClient();
 
@@ -382,16 +478,33 @@ public class HttpClientTest {
             server.waitedStart(10000);
         }
 
+        Response response;
         final HttpClient clientPap = HttpClientFactoryInstance.getClientFactory().get("PAP");
-        final Response response = clientPap.get();
+        response = clientPap.get();
         assertEquals(200, response.getStatus());
 
         final HttpClient clientPdp = HttpClientFactoryInstance.getClientFactory().get("PDP");
-        final Response response2 = clientPdp.get("test");
-        assertEquals(500, response2.getStatus());
+        response = clientPdp.get("test");
+        assertEquals(500, response.getStatus());
 
         assertFalse(MyJacksonProvider.hasWrittenSome());
         assertFalse(MyGsonProvider.hasWrittenSome());
+
+        // try with empty path
+        response = clientPap.get("");
+        assertEquals(200, response.getStatus());
+
+        // try it asynchronously, too
+        MyCallback callback = new MyCallback();
+        response = clientPap.get(callback).get();
+        verifyCallback("testHttpAuthClientProps", callback, response);
+        assertEquals(200, response.getStatus());
+
+        // try it asynchronously, with empty path
+        callback = new MyCallback();
+        response = clientPap.get(callback, "").get();
+        verifyCallback("testHttpAuthClientProps - empty path", callback, response);
+        assertEquals(200, response.getStatus());
     }
 
     @Test
@@ -497,4 +610,29 @@ public class HttpClientTest {
 
     }
 
+    class MyCallback implements InvocationCallback<Response> {
+        @Getter
+        private Response response;
+
+        @Getter
+        private Throwable throwable;
+
+        private CountDownLatch latch = new CountDownLatch(1);
+
+        @Override
+        public void completed(Response response) {
+            this.response = response;
+            latch.countDown();
+        }
+
+        @Override
+        public void failed(Throwable throwable) {
+            this.throwable = throwable;
+            latch.countDown();
+        }
+
+        public boolean await() throws InterruptedException {
+            return latch.await(5, TimeUnit.SECONDS);
+        }
+    }
 }