RESOLVED - bug 275722: [rest] REST abstraction for ECF

https://bugs.eclipse.org/bugs/show_bug.cgi?id=275722

11 files changed, 322 insertions, 77 deletions

diff --git a/framework/bundles/org.eclipse.ecf.remoteservice.rest/.project b/framework/bundles/org.eclipse.ecf.remoteservice.rest/.project
index 461918136..f6106ebfa 100644
--- a/framework/bundles/org.eclipse.ecf.remoteservice.rest/.project
+++ b/framework/bundles/org.eclipse.ecf.remoteservice.rest/.project
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <projectDescription>
-	<name>org.eclipse.ecf.internal.remoteservice.rest</name>
+	<name>org.eclipse.ecf.remoteservice.rest</name>
 	<comment></comment>
 	<projects>
 	</projects>
@@ -20,6 +20,11 @@
 			<arguments>
 			</arguments>
 		</buildCommand>
+		<buildCommand>
+			<name>org.eclipse.pde.ds.core.builder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
 	</buildSpec>
 	<natures>
 		<nature>org.eclipse.pde.PluginNature</nature>
diff --git a/framework/bundles/org.eclipse.ecf.remoteservice.rest/META-INF/MANIFEST.MF b/framework/bundles/org.eclipse.ecf.remoteservice.rest/META-INF/MANIFEST.MF
index c280292d8..cdd3cf4a1 100644
--- a/framework/bundles/org.eclipse.ecf.remoteservice.rest/META-INF/MANIFEST.MF
+++ b/framework/bundles/org.eclipse.ecf.remoteservice.rest/META-INF/MANIFEST.MF
@@ -26,4 +26,7 @@ Import-Package: org.apache.commons.httpclient;version="3.0.1",
  org.eclipse.equinox.concurrent.future;version="1.0.0",
  org.osgi.framework;version="1.5.0",
  org.osgi.util.tracker;version="1.4.2"
-Require-Bundle: org.eclipse.ecf;bundle-version="3.0.0"
+Require-Bundle: org.eclipse.ecf;bundle-version="3.0.0",
+ org.eclipse.equinox.ds;bundle-version="[1.1.0,2.0.0)";resolution:=optional,
+ org.eclipse.osgi.services;bundle-version="3.2.0"
+Service-Component: META-INF/dspresent.xml
diff --git a/framework/bundles/org.eclipse.ecf.remoteservice.rest/META-INF/dspresent.xml b/framework/bundles/org.eclipse.ecf.remoteservice.rest/META-INF/dspresent.xml
new file mode 100644
index 000000000..d33bb0266
--- /dev/null
+++ b/framework/bundles/org.eclipse.ecf.remoteservice.rest/META-INF/dspresent.xml
@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<scr:component xmlns:scr="http://www.osgi.org/xmlns/scr/v1.1.0" name="org.eclipse.ecf.remoteservice.rest">
+   <implementation class="org.eclipse.ecf.remoteservice.rest.util.DSPresent"/>
+   <service>
+      <provide interface="org.eclipse.ecf.remoteservice.rest.util.IDSPresent"/>
+   </service>
+</scr:component>
diff --git a/framework/bundles/org.eclipse.ecf.remoteservice.rest/build.properties b/framework/bundles/org.eclipse.ecf.remoteservice.rest/build.properties
index 2dcc4bdc6..68dc42252 100644
--- a/framework/bundles/org.eclipse.ecf.remoteservice.rest/build.properties
+++ b/framework/bundles/org.eclipse.ecf.remoteservice.rest/build.properties
@@ -1,6 +1,7 @@
-source.. = src/
 output.. = bin/
 bin.includes = META-INF/,\
                .,\
                plugin.xml,\
-               bin/
+               bin/,\
+               META-INF/dspresent.xml
+source.. = src/
diff --git a/framework/bundles/org.eclipse.ecf.remoteservice.rest/src/org/eclipse/ecf/internal/remoteservice/rest/Activator.java b/framework/bundles/org.eclipse.ecf.remoteservice.rest/src/org/eclipse/ecf/internal/remoteservice/rest/Activator.java
index c63626ea5..b151ca928 100644
--- a/framework/bundles/org.eclipse.ecf.remoteservice.rest/src/org/eclipse/ecf/internal/remoteservice/rest/Activator.java
+++ b/framework/bundles/org.eclipse.ecf.remoteservice.rest/src/org/eclipse/ecf/internal/remoteservice/rest/Activator.java
@@ -1,18 +1,20 @@
 /******************************************************************************* 
-* Copyright (c) 2009 EclipseSource and others. All rights reserved. This
-* program and the accompanying materials are made available under the terms of
-* the Eclipse Public License v1.0 which accompanies this distribution, and is
-* available at http://www.eclipse.org/legal/epl-v10.html
-*
-* Contributors:
-*   EclipseSource - initial API and implementation
-*******************************************************************************/ 
+ * Copyright (c) 2009 EclipseSource and others. All rights reserved. This
+ * program and the accompanying materials are made available under the terms of
+ * the Eclipse Public License v1.0 which accompanies this distribution, and is
+ * available at http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *   EclipseSource - initial API and implementation
+ *******************************************************************************/
 package org.eclipse.ecf.internal.remoteservice.rest;
 
+import org.eclipse.ecf.remoteservice.rest.IRestResourceRepresentationFactory;
 import org.eclipse.ecf.remoteservice.rest.resource.IRestResource;
 import org.eclipse.ecf.remoteservice.rest.resource.XMLResource;
 import org.osgi.framework.BundleActivator;
 import org.osgi.framework.BundleContext;
+import org.osgi.framework.ServiceRegistration;
 
 /**
  * The activator class controls the plug-in life cycle
@@ -26,43 +28,64 @@ public class Activator implements BundleActivator {
 	private static Activator plugin;
 
 	private BundleContext context;
-	
+
+	private ServiceRegistration factoryRegistration;
+
+	private ServiceRegistration resourceRegistration;
 
 	/*
 	 * (non-Javadoc)
-	 * @see org.eclipse.core.runtime.Plugins#start(org.osgi.framework.BundleContext)
+	 * 
+	 * @see
+	 * org.eclipse.core.runtime.Plugins#start(org.osgi.framework.BundleContext)
 	 */
 	public void start(BundleContext context) throws Exception {
 		plugin = this;
 		this.context = context;
-		registerXMLService( context );
+		this.factoryRegistration = registerResourceRepresentationFactory(context);
+		this.resourceRegistration = registerXMLService(context);
+	}
+
+	private ServiceRegistration registerResourceRepresentationFactory(BundleContext context) {
+		IRestResourceRepresentationFactory factory = new ResourceRepresentationFactory();
+		return context.registerService(IRestResourceRepresentationFactory.class.getName(), factory, null);
 	}
 
-	private void registerXMLService(BundleContext context) {
+	private ServiceRegistration registerXMLService(BundleContext context) {
 		IRestResource xmlResource = new XMLResource();
-		context.registerService(IRestResource.class.getName(), xmlResource, null);
+		return context.registerService(IRestResource.class.getName(), xmlResource, null);
 	}
 
 	/*
 	 * (non-Javadoc)
-	 * @see org.eclipse.core.runtime.Plugin#stop(org.osgi.framework.BundleContext)
+	 * 
+	 * @see
+	 * org.eclipse.core.runtime.Plugin#stop(org.osgi.framework.BundleContext)
 	 */
 	public void stop(BundleContext context) throws Exception {
 		plugin = null;
+		unregister(factoryRegistration);
+		unregister(resourceRegistration);
+	}
+
+	private void unregister(ServiceRegistration registration) {
+		if (registration != null) {
+			registration.unregister();
+		}
 	}
 
 	/**
 	 * Returns the shared instance
-	 *
+	 * 
 	 * @return the shared instance
 	 */
 	public static synchronized Activator getDefault() {
-		if(plugin == null) {
-			plugin = new Activator();			
+		if (plugin == null) {
+			plugin = new Activator();
 		}
 		return plugin;
 	}
-	
+
 	public BundleContext getContext() {
 		return context;
 	}
diff --git a/framework/bundles/org.eclipse.ecf.remoteservice.rest/src/org/eclipse/ecf/internal/remoteservice/rest/ResourceRepresentationFactory.java b/framework/bundles/org.eclipse.ecf.remoteservice.rest/src/org/eclipse/ecf/internal/remoteservice/rest/ResourceRepresentationFactory.java
index b193cbf36..6f559ed91 100644
--- a/framework/bundles/org.eclipse.ecf.remoteservice.rest/src/org/eclipse/ecf/internal/remoteservice/rest/ResourceRepresentationFactory.java
+++ b/framework/bundles/org.eclipse.ecf.remoteservice.rest/src/org/eclipse/ecf/internal/remoteservice/rest/ResourceRepresentationFactory.java
@@ -1,12 +1,14 @@
 /******************************************************************************* 
-* Copyright (c) 2009 EclipseSource and others. All rights reserved. This
-* program and the accompanying materials are made available under the terms of
-* the Eclipse Public License v1.0 which accompanies this distribution, and is
-* available at http://www.eclipse.org/legal/epl-v10.html
-*
-* Contributors:
-*   EclipseSource - initial API and implementation
-*******************************************************************************/ 
+ * Copyright (c) 2009 EclipseSource and others. All rights reserved. This
+
+ * program and the accompanying materials are made available under the terms of
+ * the Eclipse Public License v1.0 which accompanies this distribution, and is
+ * available at http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *   EclipseSource - initial API and implementation
+ *   Andre Dietisheim - support declaratively registered resource representations
+ *******************************************************************************/
 package org.eclipse.ecf.internal.remoteservice.rest;
 
 import java.io.IOException;
@@ -17,6 +19,7 @@ import java.util.List;
 import org.apache.commons.httpclient.HttpMethod;
 import org.eclipse.core.runtime.IAdaptable;
 import org.eclipse.ecf.remoteservice.rest.IRestCall;
+import org.eclipse.ecf.remoteservice.rest.IRestResourceRepresentationFactory;
 import org.eclipse.ecf.remoteservice.rest.resource.IRestResource;
 import org.osgi.framework.BundleContext;
 import org.osgi.framework.BundleEvent;
@@ -25,89 +28,168 @@ import org.osgi.framework.InvalidSyntaxException;
 import org.osgi.framework.ServiceReference;
 import org.osgi.util.tracker.ServiceTracker;
 
-public class ResourceRepresentationFactory implements IAdaptable {
-	
-	private static ResourceRepresentationFactory factory;
+/**
+ * A factory for creating ResourceRepresentation objects.
+ */
+public class ResourceRepresentationFactory implements IRestResourceRepresentationFactory, IAdaptable {
+
+	/** The resources. */
 	private List resources = new ArrayList();
-	
+
+	/**
+	 * The Class RestResourceTracker.
+	 */
 	private class RestResourceTracker extends ServiceTracker {
 
+		/**
+		 * Instantiates a new rest resource tracker.
+		 * 
+		 * @param context
+		 *            the context
+		 */
 		public RestResourceTracker(BundleContext context) {
-			super(context, IRestResource.class.getName(), null);			
+			super(context, IRestResource.class.getName(), null);
 		}
-		
+
+		/*
+		 * (non-Javadoc)
+		 * 
+		 * @see
+		 * org.osgi.util.tracker.ServiceTracker#addingService(org.osgi.framework
+		 * .ServiceReference)
+		 */
 		public Object addingService(ServiceReference reference) {
 			Object service = context.getService(reference);
-			if(service != null && service instanceof IRestResource) {
-				if(!resources.contains(service))
-					resources.add(service);
+			if (service instanceof IRestResource) {
+				addResourceRepresentation((IRestResource) service);
 			}
 			return service;
 		}
-		
+
+		/*
+		 * (non-Javadoc)
+		 * 
+		 * @see
+		 * org.osgi.util.tracker.ServiceTracker#removedService(org.osgi.framework
+		 * .ServiceReference, java.lang.Object)
+		 */
 		public void removedService(ServiceReference reference, Object service) {
-			resources.remove(service);
-			context.ungetService(reference);
+			if (service instanceof IRestResource) {
+				removeResourceRepresentation((IRestResource) service);
+				context.ungetService(reference);
+			}
 		}
-		
-	}
-	
-	private ResourceRepresentationFactory() {
-		
 	}
 
-	public static ResourceRepresentationFactory getDefault() {
-		if(factory == null) {
-			factory = new ResourceRepresentationFactory();
-			factory.init();
-		}
-		return factory;
+	/**
+	 * Instantiates a new resource representation factory.
+	 */
+	public ResourceRepresentationFactory() {
+		init();
 	}
 
+	/**
+	 * Inits the.
+	 */
 	private void init() {
 		Activator activator = Activator.getDefault();
 		BundleContext context = activator.getContext();
 		try {
-			ServiceReference[] references = context.getServiceReferences(IRestResource.class.getName(), null);
-			for (int i = 0; i < references.length; i++) {
-				Object service = context.getService(references[i]);
-				if(service instanceof IRestResource)
-					resources.add((IRestResource)service);
-			}
+			addResourceRepresentations(context);
 		} catch (InvalidSyntaxException e) {
-			e.printStackTrace();
+			// ignore
 		}
+		initServiceTracker(activator, context);
+	}
+
+	/**
+	 * Inits the service tracker.
+	 * 
+	 * @param activator
+	 *            the activator
+	 * @param context
+	 *            the context
+	 */
+	private void initServiceTracker(Activator activator, BundleContext context) {
 		final ServiceTracker resourceTracker = new RestResourceTracker(context);
 		resourceTracker.open();
+
 		activator.getContext().addBundleListener(new BundleListener() {
-			
+
 			public void bundleChanged(BundleEvent event) {
-				if(event.getType() == BundleEvent.STOPPING)
+				if (event.getType() == BundleEvent.STOPPING)
 					resourceTracker.close();
 			}
 		});
 	}
 
 	/**
-	 * Creates a resource representation for the resource defined in {@link IRestCall}'s 
-	 * getEstimatedResourceIdentifier() Method. This will be compared with all
-	 * registered services of the type {@link IRestResource} by calling their getIdentifier()
-	 * methods. If a service matches the estimated identifier it's parse method will
-	 * be invoked to parse the content of the resource.
+	 * Adds the resource representations.
+	 * 
+	 * @param context
+	 *            the context
+	 * 
+	 * @throws InvalidSyntaxException
+	 *             the invalid syntax exception
 	 */
-	public Object createResourceRepresentation(HttpMethod method, IRestCall restCall) throws ParseException, IOException {
+	private void addResourceRepresentations(BundleContext context) throws InvalidSyntaxException {
+		ServiceReference[] references = context.getServiceReferences(IRestResource.class.getName(), null);
+		if (references != null) {
+			for (int i = 0; i < references.length; i++) {
+				Object service = context.getService(references[i]);
+				if (service instanceof IRestResource)
+					addResourceRepresentation((IRestResource) service);
+			}
+		}
+	}
+
+	/**
+	 * Creates a resource representation for the resource defined in
+	 * {@link IRestCall}'s getEstimatedResourceIdentifier() Method. This will be
+	 * compared with all registered services of the type {@link IRestResource}
+	 * by calling their getIdentifier() methods. If a service matches the
+	 * estimated identifier it's parse method will be invoked to parse the
+	 * content of the resource.
+	 */
+	public Object createResourceRepresentation(HttpMethod method, IRestCall restCall) throws ParseException,
+			IOException {
 		for (int i = 0; i < resources.size(); i++) {
-			IRestResource resource = (IRestResource)resources.get(i);			
-			if(resource.getIdentifier().equals(restCall.getEstimatedResourceIdentifier()))
+			IRestResource resource = (IRestResource) resources.get(i);
+			if (resource.getIdentifier().equals(restCall.getEstimatedResourceIdentifier()))
 				return resource.createRepresentation(method.getResponseBodyAsString());
 		}
 		return null;
 	}
 
+	/**
+	 * Adds the resource representation.
+	 * 
+	 * @param restResource
+	 *            the rest resource
+	 */
+	private void addResourceRepresentation(IRestResource restResource) {
+		synchronized (resources) {
+			if (!resources.contains(restResource)) {
+				this.resources.add(restResource);
+			}
+		}
+	}
+
+	/**
+	 * Removes the resource representation.
+	 * 
+	 * @param restResource
+	 *            the rest resource
+	 */
+	private void removeResourceRepresentation(IRestResource restResource) {
+		synchronized (resources) {
+			this.resources.remove(restResource);
+		}
+	}
+
 	public Object getAdapter(Class adapter) {
 		if(adapter == List.class)
 			return resources;
 		return null;
 	}
-
 }
diff --git a/framework/bundles/org.eclipse.ecf.remoteservice.rest/src/org/eclipse/ecf/remoteservice/rest/IRestResourceRepresentationFactory.java b/framework/bundles/org.eclipse.ecf.remoteservice.rest/src/org/eclipse/ecf/remoteservice/rest/IRestResourceRepresentationFactory.java
new file mode 100644
index 000000000..5883529ff
--- /dev/null
+++ b/framework/bundles/org.eclipse.ecf.remoteservice.rest/src/org/eclipse/ecf/remoteservice/rest/IRestResourceRepresentationFactory.java
@@ -0,0 +1,21 @@
+package org.eclipse.ecf.remoteservice.rest;
+
+import java.io.IOException;
+import java.text.ParseException;
+
+import org.apache.commons.httpclient.HttpMethod;
+import org.eclipse.ecf.remoteservice.rest.resource.IRestResource;
+
+public interface IRestResourceRepresentationFactory {
+
+	/**
+	 * Creates a resource representation for the resource defined in
+	 * {@link IRestCall}'s getEstimatedResourceIdentifier() Method. This will be
+	 * compared with all registered services of the type {@link IRestResource}
+	 * by calling their getIdentifier() methods. If a service matches the
+	 * estimated identifier it's parse method will be invoked to parse the
+	 * content of the resource.
+	 */
+	public abstract Object createResourceRepresentation(HttpMethod method, IRestCall restCall) throws ParseException,
+			IOException;
+}
\ No newline at end of file
diff --git a/framework/bundles/org.eclipse.ecf.remoteservice.rest/src/org/eclipse/ecf/remoteservice/rest/RestService.java b/framework/bundles/org.eclipse.ecf.remoteservice.rest/src/org/eclipse/ecf/remoteservice/rest/RestService.java
index 8428ae155..aac56da43 100644
--- a/framework/bundles/org.eclipse.ecf.remoteservice.rest/src/org/eclipse/ecf/remoteservice/rest/RestService.java
+++ b/framework/bundles/org.eclipse.ecf.remoteservice.rest/src/org/eclipse/ecf/remoteservice/rest/RestService.java
@@ -42,7 +42,7 @@ import org.eclipse.ecf.core.security.NameCallback;
 import org.eclipse.ecf.core.security.ObjectCallback;
 import org.eclipse.ecf.core.security.UnsupportedCallbackException;
 import org.eclipse.ecf.core.util.ECFException;
-import org.eclipse.ecf.internal.remoteservice.rest.ResourceRepresentationFactory;
+import org.eclipse.ecf.internal.remoteservice.rest.Activator;
 import org.eclipse.ecf.remoteservice.IRemoteCall;
 import org.eclipse.ecf.remoteservice.IRemoteCallListener;
 import org.eclipse.ecf.remoteservice.IRemoteService;
@@ -54,6 +54,8 @@ import org.eclipse.equinox.concurrent.future.AbstractExecutor;
 import org.eclipse.equinox.concurrent.future.IFuture;
 import org.eclipse.equinox.concurrent.future.IProgressRunnable;
 import org.eclipse.equinox.concurrent.future.ThreadsExecutor;
+import org.osgi.framework.BundleContext;
+import org.osgi.framework.ServiceReference;
 
 /**
  * This class represents a REST service from the client side of view. So a RESTful
@@ -236,9 +238,8 @@ public class RestService implements IRemoteService {
 		try {
 			int responseCode = httpClient.executeMethod(httpMethod);
 			if(responseCode == HttpStatus.SC_OK) {
-				response = ResourceRepresentationFactory.getDefault()
-						.createResourceRepresentation(httpMethod, restCall);
-				if(proxy != null && proxy instanceof IRestResponseProcessor)
+				response = getResourceRepresentation(restCall, httpMethod);
+				if (proxy != null && proxy instanceof IRestResponseProcessor)
 					((IRestResponseProcessor) proxy).processResource(response);
 			} else 
 				throw new ECFException("Service returned status code: " + responseCode);
@@ -251,8 +252,46 @@ public class RestService implements IRemoteService {
 		}
 		return response;
 	}
-	
-	protected void handleRequestHeaders(HttpMethod httpMethod, Map requestHeaders) {
+
+	/**
+	 * Gets the resource representation for a given rest call and http method.
+	 * The resource representation is queried from the
+	 * IRestResourceRepresentationFactory service
+	 * 
+	 * @param restCall
+	 *            the rest call
+	 * @param httpMethod
+	 *            the http method
+	 * @param response
+	 *            the response
+	 * 
+	 * @return the resource representation
+	 * 
+	 * @throws ParseException
+	 *             the parse exception
+	 * @throws IOException
+	 *             Signals that an I/O exception has occurred.
+	 * 
+	 * @see IRestCall#getEstimatedResourceIdentifier()
+	 * @see IRestCall#getMethod()
+	 * @see IRestResourceRepresentationFactory
+	 */
+	private Object getResourceRepresentation(final IRestCall restCall, HttpMethod httpMethod) throws ParseException,
+			IOException {
+		Object response = null;
+		BundleContext context = Activator.getDefault().getContext();
+		ServiceReference serviceReference = context.getServiceReference(IRestResourceRepresentationFactory.class
+				.getName());
+		if (serviceReference != null) {
+			IRestResourceRepresentationFactory factory = (IRestResourceRepresentationFactory) context
+					.getService(serviceReference);
+			response = factory.createResourceRepresentation(httpMethod, restCall);
+		}
+		return response;
+	}
+
+	protected void handleRequestHeaders(HttpMethod httpMethod,
+			Map requestHeaders) {
 		if(requestHeaders != null) {
 			Set keySet = requestHeaders.keySet();
 			Object[] headers = keySet.toArray();
diff --git a/framework/bundles/org.eclipse.ecf.remoteservice.rest/src/org/eclipse/ecf/remoteservice/rest/util/DSPresent.java b/framework/bundles/org.eclipse.ecf.remoteservice.rest/src/org/eclipse/ecf/remoteservice/rest/util/DSPresent.java
new file mode 100644
index 000000000..fc4e149cb
--- /dev/null
+++ b/framework/bundles/org.eclipse.ecf.remoteservice.rest/src/org/eclipse/ecf/remoteservice/rest/util/DSPresent.java
@@ -0,0 +1,16 @@
+package org.eclipse.ecf.remoteservice.rest.util;
+
+/**
+ * The Class DSPresent.
+ */
+public class DSPresent implements IDSPresent {
+
+	/* (non-Javadoc)
+	 * @see org.eclipse.ecf.remoteservice.rest.util.IDSPresent#isPresent()
+	 */
+	public boolean isPresent() {
+		// if registered, it is present!
+		return true;
+	}
+	
+}
diff --git a/framework/bundles/org.eclipse.ecf.remoteservice.rest/src/org/eclipse/ecf/remoteservice/rest/util/DSUtil.java b/framework/bundles/org.eclipse.ecf.remoteservice.rest/src/org/eclipse/ecf/remoteservice/rest/util/DSUtil.java
new file mode 100644
index 000000000..9ca709ba6
--- /dev/null
+++ b/framework/bundles/org.eclipse.ecf.remoteservice.rest/src/org/eclipse/ecf/remoteservice/rest/util/DSUtil.java
@@ -0,0 +1,35 @@
+/******************************************************************************* 
+ * Copyright (c) 2009 EclipseSource and others. All rights reserved. This
+ * program and the accompanying materials are made available under the terms of
+ * the Eclipse Public License v1.0 which accompanies this distribution, and is
+ * available at http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *   Andre Dietisheim - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.ecf.remoteservice.rest.util;
+
+import org.osgi.framework.BundleContext;
+import org.osgi.framework.InvalidSyntaxException;
+import org.osgi.framework.ServiceReference;
+
+public class DSUtil {
+	/**
+	 * Checks whether the declarative services daemon is running.
+	 * 
+	 * @param context
+	 *            the context
+	 * 
+	 * @return <tt>true</tt>, if is declarative services are running
+	 */
+	public static boolean isRunning(BundleContext context) {
+		ServiceReference[] serviceReferences = null;
+		try {
+			serviceReferences = context.getServiceReferences(IDSPresent.class.getName(), null);
+		} catch (InvalidSyntaxException e) {
+			// ignore
+		}
+		return serviceReferences != null && serviceReferences.length > 0;
+	}
+
+}
diff --git a/framework/bundles/org.eclipse.ecf.remoteservice.rest/src/org/eclipse/ecf/remoteservice/rest/util/IDSPresent.java b/framework/bundles/org.eclipse.ecf.remoteservice.rest/src/org/eclipse/ecf/remoteservice/rest/util/IDSPresent.java
new file mode 100644
index 000000000..83c152c12
--- /dev/null
+++ b/framework/bundles/org.eclipse.ecf.remoteservice.rest/src/org/eclipse/ecf/remoteservice/rest/util/IDSPresent.java
@@ -0,0 +1,13 @@
+package org.eclipse.ecf.remoteservice.rest.util;
+
+public interface IDSPresent {
+
+	/**
+	 * Checks whether declarative service is present. This service is configured
+	 * by declarative services, so if it's registered to the OSGI runtime, DS is
+	 * present
+	 * 
+	 * @return true, if is present
+	 */
+	public boolean isPresent();
+}
\ No newline at end of file