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diff --git a/workflow-designer-ui/src/main/java/org/onap/workflow/web/TransparentProxy.java b/workflow-designer-ui/src/main/java/org/onap/workflow/web/TransparentProxy.java
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+++ b/workflow-designer-ui/src/main/java/org/onap/workflow/web/TransparentProxy.java
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+package org.onap.workflow.web;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Enumeration;
+import javax.servlet.ServletConfig;
+import javax.servlet.ServletContext;
+import javax.servlet.ServletException;
+import org.eclipse.jetty.proxy.ProxyServlet;
+
+/**
+ * <p>A naive implementation of transparent proxy based on
+ * <a href="https://www.eclipse.org/jetty/documentation/9.4.x/proxy-servlet.html">Jetty proxy servlet</a>.
+ * The only difference is that the <code>proxyTo</code> configuration parameter is taken from a JVM argument (and can
+ * be therefore injected via an environment variable), instead of an <code>init-param</code> in <i>web.xml</i>.</p>
+ * <p>Example: <code>java -DproxyTo=http://172.17.0.9:8080 -jar $JETTY_HOME/start.jar</code></p>
+ * <p>If you get a <i>502 Bad Gateway</i> error:</p>
+ * <ul>
+ *     <ol>
+ *         Make sure that Jetty 'proxy' module
+ *         <a href="https://www.eclipse.org/jetty/documentation/9.4.x/startup-modules.html">is not enabled</a>.
+ *     </ol>
+ *     <ol>
+ *         Check the value of <code>proxyTo</code>. Make sure it does not redirect to the proxy server itself.
+ *     </ol>
+ *     <ol>
+ *         Make sure there is no proxy (e.g. in a corporate environment) between the servlet and <code>proxyTo</code>.
+ *     </ol>
+ * </ul>
+ *
+ * @author evitaliy
+ * @since 16 Jul 2018
+ */
+public class TransparentProxy extends ProxyServlet.Transparent {
+
+    @Override
+    public void init(ServletConfig config) throws ServletException {
+        super.init(new ServletConfigWrapper(config));
+    }
+
+    private class ServletConfigWrapper implements ServletConfig {
+
+        private static final String PROXY_TO = "proxyTo";
+
+        private final String proxyTo;
+        private final ServletConfig config;
+
+        ServletConfigWrapper(ServletConfig config) throws ServletException {
+
+            this.proxyTo = System.getProperty(PROXY_TO);
+            if (this.proxyTo == null) {
+                throw new ServletException("-D" + PROXY_TO + " must be specified");
+            }
+
+            this.config = config;
+        }
+
+        @Override
+        public String getServletName() {
+            return config.getServletName();
+        }
+
+        @Override
+        public ServletContext getServletContext() {
+            return config.getServletContext();
+        }
+
+        @Override
+        public String getInitParameter(String s) {
+            return PROXY_TO.equals(s) ? this.proxyTo : config.getInitParameter(s);
+        }
+
+        @Override
+        public Enumeration<String> getInitParameterNames() {
+            ArrayList<String> params = Collections.list(config.getInitParameterNames());
+            params.add(PROXY_TO);
+            return Collections.enumeration(params);
+        }
+    }
+}