1 files changed, 207 insertions, 0 deletions
diff --git a/message-router/consumer/provider/src/main/java/org/onap/ccsdk/sli/adaptors/messagerouter/consumer/provider/impl/AbstractBaseConsumer.java b/message-router/consumer/provider/src/main/java/org/onap/ccsdk/sli/adaptors/messagerouter/consumer/provider/impl/AbstractBaseConsumer.java
new file mode 100755
index 00000000..8937f7b9
--- /dev/null
+++ b/message-router/consumer/provider/src/main/java/org/onap/ccsdk/sli/adaptors/messagerouter/consumer/provider/impl/AbstractBaseConsumer.java
@@ -0,0 +1,207 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * openECOMP : SDN-C
+ * ================================================================================
+ * Copyright (C) 2017 - 2018 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.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.ccsdk.sli.adaptors.messagerouter.consumer.provider.impl;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.net.HttpURLConnection;
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.util.Base64;
+
+import javax.net.ssl.HostnameVerifier;
+import javax.net.ssl.HttpsURLConnection;
+import javax.net.ssl.SSLSession;
+
+import org.onap.ccsdk.sli.adaptors.messagerouter.consumer.api.ConsumerApi;
+import org.onap.ccsdk.sli.adaptors.messagerouter.consumer.api.RequestHandler;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import com.google.gson.Gson;
+import com.google.gson.JsonParseException;
+
+/*
+ * java.net based client to build message router consumers
+ */
+public abstract class AbstractBaseConsumer implements ConsumerApi {
+    private static final Logger LOG = LoggerFactory.getLogger(AbstractBaseConsumer.class);
+    private static final String REQUEST_METHOD = "GET";
+
+    private final String host;
+    private final Integer connectTimeout;
+    private final Integer readTimeout;
+    private final String group;
+    private final String id;
+    private final String filter;
+    private final Integer limit;
+    private final Integer timeoutQueryParamValue;
+    private final String authorizationString;
+
+    protected RequestHandler requestHandler;
+    protected URL url;
+    protected String topic;
+    
+    public AbstractBaseConsumer(String username, String password, String host, String authentication, Integer connectTimeout, Integer readTimeout, String group, String id, String filter, Integer limit, Integer timeoutQueryParamValue) {
+	this.host = host;
+	this.connectTimeout = connectTimeout;
+	this.readTimeout = readTimeout;
+	this.group = group;
+	this.id = id;
+	this.filter = filter;
+	this.limit = limit;
+	this.timeoutQueryParamValue = timeoutQueryParamValue;
+
+	if ("basic".equals(authentication)) {
+	    if (username != null && password != null && username.length() > 0 && password.length() > 0) {
+		authorizationString = buildAuthorizationString(username, password);
+	    } else {
+		throw new IllegalStateException("Authentication is set to basic but username or password is missing");
+	    }
+	} else if ("noauth".equals(authentication)) {
+	    authorizationString = null;
+	} else {
+	    throw new IllegalStateException("Unknown authentication method: " + authentication);
+	}
+    }
+
+    protected void poll() {
+	String responseBody = performHttpOperation();
+	if (responseBody != null && !responseBody.startsWith("[]")) {
+	    LOG.info("New message was fetched from MessageRouter.");
+	    LOG.trace("Fetched message is\n{}", responseBody);
+	    try {
+		String[] requests = new Gson().fromJson(responseBody, String[].class);
+		if (requests != null) {
+		    for (String request : requests) {
+			if (request != null) {
+			    requestHandler.handleRequest(topic,request);
+			}
+		    }
+		} else {
+		    LOG.warn("Deserialization of received message results in null array.", responseBody);
+		}
+	    } catch (JsonParseException e) {
+		LOG.warn("Received message has bad format. Expected format is JSON.");
+	    }
+	} else {
+	    LOG.trace("No new message was fetched from MessageRouter.");
+	}
+    }
+
+    private String buildlUrlString(String topic) {
+	StringBuilder sb = new StringBuilder();
+	sb.append(host + "/events/" + topic + "/" + group + "/" + id);
+	sb.append("?timeout=" + timeoutQueryParamValue);
+
+	if (limit != null) {
+	    sb.append("&limit=" + limit);
+	}
+	if (filter != null) {
+	    sb.append("&filter=" + filter);
+	}
+	return sb.toString();
+    }
+
+    private String performHttpOperation() {
+	HttpURLConnection httpUrlConnection = null;
+	try {
+	    httpUrlConnection = buildHttpURLConnection(url);
+	    httpUrlConnection.setRequestMethod(REQUEST_METHOD);
+	    httpUrlConnection.connect();
+	    int status = httpUrlConnection.getResponseCode();
+	    if (status < 300) {
+		return readFromStream(httpUrlConnection.getInputStream());
+	    } else {
+		String response = readFromStream(httpUrlConnection.getErrorStream());
+		LOG.warn("Fetching message from MessageRouter on url {} failed with http status {}. Error message is\n{}.", url, status, response);
+	    }
+	} catch (Exception e) {
+	    LOG.warn("Exception was thrown during fetching message from MessageRouter on url {}.", url, e);
+	} finally {
+	    if (httpUrlConnection != null) {
+		httpUrlConnection.disconnect();
+	    }
+	}
+	return null;
+    }
+
+    private String buildAuthorizationString(String userName, String password) {
+	String basicAuthString = userName + ":" + password;
+	basicAuthString = Base64.getEncoder().encodeToString(basicAuthString.getBytes());
+	return "Basic " + basicAuthString;
+    }
+
+    protected HttpURLConnection buildHttpURLConnection(URL url) throws IOException {
+	HttpURLConnection httpUrlConnection = (HttpURLConnection) url.openConnection();
+	if (authorizationString != null) {
+	    httpUrlConnection.setRequestProperty("Authorization", authorizationString);
+	}
+	httpUrlConnection.setRequestProperty("Accept", "application/json");
+	httpUrlConnection.setUseCaches(false);
+	httpUrlConnection.setConnectTimeout(connectTimeout);
+	httpUrlConnection.setReadTimeout(readTimeout);
+
+	// ignore hostname errors when dealing with HTTPS connections
+	if (httpUrlConnection instanceof HttpsURLConnection) {
+	    HttpsURLConnection conn = (HttpsURLConnection) httpUrlConnection;
+	    conn.setHostnameVerifier(new HostnameVerifier() {
+		@Override
+		public boolean verify(String arg0, SSLSession arg1) {
+		    return true;
+		}
+	    });
+	}
+	return httpUrlConnection;
+    }
+
+    protected String readFromStream(InputStream stream) throws IOException {
+	BufferedReader br = new BufferedReader(new InputStreamReader(stream));
+	StringBuilder sb = new StringBuilder();
+	String line;
+	while ((line = br.readLine()) != null) {
+	    sb.append(line);
+	    sb.append("\n");
+	}
+	br.close();
+	return sb.toString();
+    }
+
+    @Override
+    public void registerHandler(String topic, RequestHandler requestHandler) {
+	this.topic = topic;
+	try {
+	    this.url = new URL(buildlUrlString(topic));
+	} catch (MalformedURLException e) {
+	    LOG.error("Topic " + topic + " resulted in MalformedURLException", e);
+	}
+	this.requestHandler = requestHandler;
+    }
+
+    @Override
+    public void close() throws Exception {
+	//BaseConsumer doesn't spawn any threads
+    }
+
+}