2 * ============LICENSE_START=======================================================
3 * Copyright (C) 2016-2018 Ericsson. All rights reserved.
4 * Modifications Copyright (C) 2019-2020 Nordix Foundation.
5 * ================================================================================
6 * Licensed under the Apache License, Version 2.0 (the "License");
7 * you may not use this file except in compliance with the License.
8 * You may obtain a copy of the License at
10 * http://www.apache.org/licenses/LICENSE-2.0
12 * Unless required by applicable law or agreed to in writing, software
13 * distributed under the License is distributed on an "AS IS" BASIS,
14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15 * See the License for the specific language governing permissions and
16 * limitations under the License.
18 * SPDX-License-Identifier: Apache-2.0
19 * ============LICENSE_END=========================================================
22 package org.onap.policy.apex.plugins.event.carrier.restclient;
24 import java.util.Properties;
25 import java.util.regex.Matcher;
26 import java.util.regex.Pattern;
27 import javax.ws.rs.client.Client;
28 import javax.ws.rs.client.ClientBuilder;
29 import javax.ws.rs.core.Response;
30 import org.apache.commons.lang3.StringUtils;
31 import org.onap.policy.apex.core.infrastructure.threading.ThreadUtilities;
32 import org.onap.policy.apex.service.engine.event.ApexEventException;
33 import org.onap.policy.apex.service.engine.event.ApexEventReceiver;
34 import org.onap.policy.apex.service.engine.event.ApexEventRuntimeException;
35 import org.onap.policy.apex.service.engine.event.ApexPluginsEventConsumer;
36 import org.onap.policy.apex.service.parameters.carriertechnology.RestPluginCarrierTechnologyParameters;
37 import org.onap.policy.apex.service.parameters.eventhandler.EventHandlerParameters;
38 import org.slf4j.Logger;
39 import org.slf4j.LoggerFactory;
42 * This class implements an Apex event consumer that receives events from a REST server.
44 * @author Liam Fallon (liam.fallon@ericsson.com)
46 public class ApexRestClientConsumer extends ApexPluginsEventConsumer {
47 // Get a reference to the logger
48 private static final Logger LOGGER = LoggerFactory.getLogger(ApexRestClientConsumer.class);
50 // The amount of time to wait in milliseconds between checks that the consumer thread has stopped
51 private static final long REST_CLIENT_WAIT_SLEEP_TIME = 50;
53 // The Key for property
54 private static final String HTTP_CODE_STATUS = "HTTP_CODE_STATUS";
56 // The REST parameters read from the parameter service
57 private RestClientCarrierTechnologyParameters restConsumerProperties;
59 // The event receiver that will receive events from this consumer
60 private ApexEventReceiver eventReceiver;
62 // The HTTP client that makes a REST call to get an input event for Apex
63 private Client client;
65 // The pattern for filtering status code
66 private Pattern httpCodeFilterPattern = null;
69 public void init(final String consumerName, final EventHandlerParameters consumerParameters,
70 final ApexEventReceiver incomingEventReceiver) throws ApexEventException {
71 this.eventReceiver = incomingEventReceiver;
72 this.name = consumerName;
74 // Check and get the REST Properties
75 if (!(consumerParameters.getCarrierTechnologyParameters() instanceof RestClientCarrierTechnologyParameters)) {
76 final String errorMessage =
77 "specified consumer properties are not applicable to REST client consumer (" + this.name + ")";
78 LOGGER.warn(errorMessage);
79 throw new ApexEventException(errorMessage);
81 restConsumerProperties =
82 (RestClientCarrierTechnologyParameters) consumerParameters.getCarrierTechnologyParameters();
84 this.httpCodeFilterPattern = Pattern.compile(restConsumerProperties.getHttpCodeFilter());
86 // Check if the HTTP method has been set
87 if (restConsumerProperties.getHttpMethod() == null) {
88 restConsumerProperties.setHttpMethod(RestPluginCarrierTechnologyParameters.HttpMethod.GET);
91 if (!RestPluginCarrierTechnologyParameters.HttpMethod.GET.equals(restConsumerProperties.getHttpMethod())) {
92 final String errorMessage = "specified HTTP method of \"" + restConsumerProperties.getHttpMethod()
93 + "\" is invalid, only HTTP method \"GET\" "
94 + "is supported for event reception on REST client consumer (" + this.name + ")";
95 LOGGER.warn(errorMessage);
96 throw new ApexEventException(errorMessage);
99 // Initialize the HTTP client
100 client = ClientBuilder.newClient();
108 // The RequestRunner thread runs the get request for the event
109 Thread requestRunnerThread = null;
111 // The endless loop that receives events using REST calls
112 while (consumerThread.isAlive() && !stopOrderedFlag) {
113 // Create a new request if one is not in progress
114 if (requestRunnerThread == null || !requestRunnerThread.isAlive()) {
115 requestRunnerThread = new Thread(new RequestRunner());
116 requestRunnerThread.start();
119 ThreadUtilities.sleep(REST_CLIENT_WAIT_SLEEP_TIME);
130 stopOrderedFlag = true;
132 while (consumerThread.isAlive()) {
133 ThreadUtilities.sleep(REST_CLIENT_WAIT_SLEEP_TIME);
138 * This class is used to start a thread for each request issued.
140 * @author Liam Fallon (liam.fallon@ericsson.com)
142 private class RequestRunner implements Runnable {
149 final Response response = client.target(restConsumerProperties.getUrl()).request("application/json")
150 .headers(restConsumerProperties.getHttpHeadersAsMultivaluedMap()).get();
152 // Match the return code
153 Matcher isPass = httpCodeFilterPattern.matcher(String.valueOf(response.getStatus()));
155 // Check that status code
156 if (!isPass.matches()) {
157 final String errorMessage = "reception of event from URL \"" + restConsumerProperties.getUrl()
158 + "\" failed with status code " + response.getStatus() + " and message \""
159 + response.readEntity(String.class) + "\"";
160 LOGGER.warn(errorMessage);
161 throw new ApexEventRuntimeException(errorMessage);
164 // Get the event we received
165 final String eventJsonString = response.readEntity(String.class);
167 // Check there is content
168 if (StringUtils.isBlank(eventJsonString)) {
169 final String errorMessage =
170 "received an empty event from URL \"" + restConsumerProperties.getUrl() + "\"";
171 throw new ApexEventRuntimeException(errorMessage);
174 // build a key and value property in excutionProperties
175 Properties executionProperties = new Properties();
176 executionProperties.put(HTTP_CODE_STATUS, response.getStatus());
178 // Send the event into Apex
179 eventReceiver.receiveEvent(executionProperties, eventJsonString);
180 } catch (final Exception e) {
181 LOGGER.warn("error receiving events on thread {}", consumerThread.getName(), e);
187 * Hook for unit test mocking of HTTP client.
189 * @param client the mocked client
191 protected void setClient(final Client client) {
192 this.client = client;