added gateway mode to decide to which oauth app to use.

components/device-mgt/org.wso2.carbon.device.mgt.ui/src/main/resources/jaggeryapps/devicemgt/app/conf/config.json

@@ -12,6 +12,7 @@
     "iOSConfigRoot" : "%https.ip%/ios-enrollment/",
     "iOSAPIRoot" : "%https.ip%/ios/",
     "adminService": "%https.ip%",
+    "apimgt-gateway": false,
     "oauthProvider": {
         "appRegistration": {
             "appType": "webapp",

components/device-mgt/org.wso2.carbon.device.mgt.ui/src/main/resources/jaggeryapps/devicemgt/app/modules/oauth/token-handlers.js

@@ -142,6 +142,7 @@ var handlers = function () {
                     "client credentials to session context as the server is unable to obtain " +
                         "dynamic client credentials - setUpEncodedTenantBasedClientAppCredentials(x)");
             } else {
+                if (devicemgtProps["apimgt-gateway"]) {
                     var jwtToken = tokenUtil.getAccessTokenByJWTGrantType(dynamicClientAppCredentials);
                     if (!jwtToken) {
                         throw new Error("{/app/modules/oauth/token-handlers.js} Could not set up encoded tenant based " +
@@ -163,6 +164,14 @@ var handlers = function () {
                                 encodedTenantBasedClientAppCredentials);
                         }
                     }
+                } else {
+                    var encodedTenantBasedClientAppCredentials =
+                        tokenUtil.encode(dynamicClientAppCredentials["clientId"] + ":" +
+                        dynamicClientAppCredentials["clientSecret"]);
+                    // setting up encoded tenant based client credentials to session context.
+                    session.put(constants["ENCODED_TENANT_BASED_CLIENT_APP_CREDENTIALS"],
+                        encodedTenantBasedClientAppCredentials);
+                }
             }
         }
     };