Utils created

src/webapp/src/java/org/wyona/yanel/servlet/Utils.java

@@ -0,0 +1,108 @@
+/*
+ * See the NOTICE.txt file distributed with
+ * this work for additional information regarding copyright ownership.
+ * Wyona licenses this file to You 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.
+ */
+package org.wyona.yanel.servlet;
+
+import java.net.URL;
+
+import org.apache.logging.log4j.Logger;
+import org.apache.logging.log4j.LogManager;
+
+import org.wyona.yanel.core.map.Realm;
+import org.wyona.yanel.core.map.ReverseProxyConfig;
+
+import javax.servlet.http.HttpServletRequest;
+
+/**
+ * Utilities
+ */
+public class Utils {
+
+    private static Logger log = LogManager.getLogger(Utils.class);
+
+    /**
+     * Patch request with proxy settings re realm configuration
+     * @param realm Realm associated with request
+     * @param request Request which Yanel received
+     * @param addQS Additonal query string
+     * @param xml Flag whether returned URL should be XML compatible, e.g. re ampersands
+     * @return URL which was received by reverse proxy, e.g. http://www.yanel.org/en/download/index.html instead http://127.0.0.1:8080/yanel/yanel-website/en/download/index.html
+     */
+    public static String getRequestURLQS(Realm realm, HttpServletRequest request, String addQS, boolean xml) {
+        try {
+            // TODO: Handle this exception more gracefully!
+            if (realm == null) log.error("No realm found for path " +request.getServletPath());
+
+            String proxyHostName = realm.getProxyHostName();
+            int proxyPort = realm.getProxyPort();
+            String proxyPrefix = realm.getProxyPrefix();
+            ReverseProxyConfig reverseProxyConfig = realm.getReverseProxyConfig();
+            log.warn("DEBUG BILLY: Hostname: " + realm.getProxyHostName() + ", " + reverseProxyConfig.getHostName());
+
+            URL url = new URL(request.getRequestURL().toString());
+
+            if(realm.isProxySet()) {
+                String forwardedHost = request.getHeader("X-FORWARDED-HOST");
+                if (forwardedHost != null) {
+                    url = new java.net.URL(url.getProtocol(), forwardedHost, url.getFile());
+                }
+                if (proxyHostName != null) {
+                    url = new URL(url.getProtocol(), proxyHostName, url.getFile());
+                }
+
+                if (proxyPort >= 0) {
+                    //log.debug("Configured proxy port: " + proxyPort);
+                    url = new URL(url.getProtocol(), url.getHost(), proxyPort, url.getFile());
+                } else {
+                    //log.debug("No proxy port configured, hence use default port: " + url.getDefaultPort());
+                    url = new URL(url.getProtocol(), url.getHost(), url.getFile()); // INFO: Please note that if one does not set the port explicitely, then toString() won't add the port to the returned string.
+                }
+
+                if (proxyPrefix != null) {
+                    // INFO: Remove proxy prefix, e.g. "/yanel/yanel-website"
+                    url = new URL(url.getProtocol(), url.getHost(), url.getPort(), url.getFile().substring(proxyPrefix.length()));
+                }
+
+                if (reverseProxyConfig.getReversePrefix() != null) {
+                    // INFO: Add reverse proxy prefix, e.g. "/boost2"
+                    url = new URL(url.getProtocol(), url.getHost(), url.getPort(), reverseProxyConfig.getReversePrefix() + url.getFile());
+                }
+
+                //log.debug("Proxy enabled for this realm resp. request: " + realm + ", " + url);
+            } else {
+                //log.debug("No proxy set for this realm resp. request: " + realm + ", " + url);
+            }
+
+            String urlQS = url.toString();
+            if (request.getQueryString() != null) {
+                urlQS = urlQS + "?" + request.getQueryString();
+                if (addQS != null) urlQS = urlQS + "&" + addQS;
+            } else {
+                if (addQS != null) urlQS = urlQS + "?" + addQS;
+            }
+
+            if (xml) {
+                urlQS = urlQS.replaceAll("&", "&");
+            }
+
+            if(log.isDebugEnabled()) log.debug("Request: " + urlQS);
+
+            return urlQS;
+        } catch (Exception e) {
+            log.error(e.getMessage(), e);
+            return null;
+        }
+    }
+}