Fixing API publishing related issues

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/api/mgt/APIConfig.java

@@ -18,7 +18,10 @@
  */
 package org.wso2.carbon.device.mgt.core.api.mgt;
 
+import org.wso2.carbon.apimgt.api.APIManagementException;
 import org.wso2.carbon.apimgt.api.APIProvider;
+import org.wso2.carbon.apimgt.impl.APIManagerFactory;
+import org.wso2.carbon.device.mgt.common.DeviceManagementException;
 
 import javax.xml.bind.annotation.XmlElement;
 import javax.xml.bind.annotation.XmlRootElement;
@@ -51,8 +54,12 @@ public class APIConfig {
     private String transports;
     private APIProvider provider;
 
-    public void init(APIProvider provider) {
-        this.provider = provider;
+    public void init() throws DeviceManagementException {
+        try {
+            this.provider = APIManagerFactory.getInstance().getAPIProvider(this.getOwner());
+        } catch (APIManagementException e) {
+            throw new DeviceManagementException("Error occurred while initializing API provider", e);
+        }
     }
 
     @XmlTransient

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/api/mgt/APIPublisherServiceImpl.java

@@ -42,11 +42,16 @@ public class APIPublisherServiceImpl implements APIPublisherService {
             log.debug("Publishing API '" + api.getId() + "'");
         }
         APIProvider provider = APIManagerFactory.getInstance().getAPIProvider(api.getApiOwner());
+        if (provider != null) {
             provider.addAPI(api);
             if (log.isDebugEnabled()) {
                 log.debug("Successfully published API '" + api.getId() + "' with the context '" +
                         api.getContext() + "'");
             }
+        } else {
+            log.error("API provider configured for the given API configuration is null. Thus, the API is not " +
+                    "published");
+        }
     }
 
     @Override

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/api/mgt/APIRegistrationStartupObserver.java

@@ -60,14 +60,21 @@ public class APIRegistrationStartupObserver implements ServerStartupObserver {
         List<APIConfig> apiConfigs = APIPublisherConfig.getInstance().getApiConfigs();
         for (APIConfig apiConfig : apiConfigs) {
             try {
+                /* API Config is initialized at this point in order to avoid OSGi declarative services which
+                the APIManagerComponent depend on, are deployed and initialized before invoking methods in
+                APIManagerFactory  */
+                apiConfig.init();
+
                 API api = DeviceManagerUtil.getAPI(apiConfig);
                 DeviceManagementDataHolder.getInstance().getApiPublisherService().publishAPI(api);
 
                 log.info("Successfully published API '" + apiConfig.getName() + "' with the context '" +
                         apiConfig.getContext() + "' and version '" + apiConfig.getVersion() + "'");
-            } catch (APIManagementException e) {
+            } catch (Throwable e) {
+                /* Throwable is caught as none of the RuntimeExceptions that can potentially occur at this point
+                does not seem to be logged anywhere else within the framework */
                 log.error("Error occurred while publishing API '" + apiConfig.getName() + "' with the context '" +
-                        apiConfig.getContext() + "' and version '" + apiConfig.getVersion() + "'");
+                        apiConfig.getContext() + "' and version '" + apiConfig.getVersion() + "'", e);
             }
         }
         if (log.isDebugEnabled()) {