console-proxy: fix potential NPE condition (#3419)

When checking if the console proxy URL domain starts with *, the code
does not check if the provided string is null. When domain is not
configured the IP address should be used.

Fixes #3164

Signed-off-by: Rohit Yadav <rohit.yadav@shapeblue.com>

Author: yadvr

core/src/main/java/com/cloud/info/ConsoleProxyInfo.java

@@ -55,18 +55,16 @@ public ConsoleProxyInfo(boolean sslEnabled, String proxyIpAddress, int port, int
 
     private String formatProxyAddress(String consoleProxyUrlDomain, String proxyIpAddress) {
         StringBuffer sb = new StringBuffer();
-        // Domain in format *.example.com, proxy IP is 1.2.3.4 --> 1-2-3-4.example.com
-        if (consoleProxyUrlDomain.startsWith("*")) {
+        if (StringUtils.isBlank(consoleProxyUrlDomain)) {
+            // Blank config, we use the proxy IP
+            sb.append(proxyIpAddress);
+        } else if (consoleProxyUrlDomain.startsWith("*")) {
+            // Domain in format *.example.com, proxy IP is 1.2.3.4 --> 1-2-3-4.example.com
             sb.append(proxyIpAddress.replaceAll("\\.", "-"));
             sb.append(consoleProxyUrlDomain.substring(1)); // skip the *
-
-        // Otherwise we assume a valid domain if config not blank
-        } else if (StringUtils.isNotBlank(consoleProxyUrlDomain)) {
-            sb.append(consoleProxyUrlDomain);
-
-        // Blank config, we use the proxy IP
         } else {
-            sb.append(proxyIpAddress);
+            // Otherwise we assume a valid domain if config not blank
+            sb.append(consoleProxyUrlDomain);
         }
         return sb.toString();
     }