keycloak-aplcache

diff --git a/services/src/main/java/org/keycloak/services/resources/admin/ClientTemplateResource.java b/services/src/main/java/org/keycloak/services/resources/admin/ClientTemplateResource.java
index 768bf1a..49580b1 100644
--- a/services/src/main/java/org/keycloak/services/resources/admin/ClientTemplateResource.java
+++ b/services/src/main/java/org/keycloak/services/resources/admin/ClientTemplateResource.java
@@ -22,6 +22,7 @@ import org.keycloak.events.admin.OperationType;
 import org.keycloak.models.ClientTemplateModel;
 import org.keycloak.models.KeycloakSession;
 import org.keycloak.models.ModelDuplicateException;
+import org.keycloak.models.ModelException;
 import org.keycloak.models.RealmModel;
 import org.keycloak.models.utils.ModelToRepresentation;
 import org.keycloak.models.utils.RepresentationToModel;
@@ -133,11 +134,16 @@ public class ClientTemplateResource {
      */
     @DELETE
     @NoCache
-    public void deleteClientTemplate() {
+    public Response deleteClientTemplate() {
         auth.requireManage();
 
-        realm.removeClientTemplate(template.getId());
-        adminEvent.operation(OperationType.DELETE).resourcePath(uriInfo).success();
+        try {
+            realm.removeClientTemplate(template.getId());
+            adminEvent.operation(OperationType.DELETE).resourcePath(uriInfo).success();
+            return Response.noContent().build();
+        } catch (ModelException me) {
+            return ErrorResponse.error(me.getMessage(), Response.Status.BAD_REQUEST);
+        }
     }
 
 

diff --git a/testsuite/integration-arquillian/tests/base/src/test/java/org/keycloak/testsuite/endpoint/client/ClientTemplateTest.java b/testsuite/integration-arquillian/tests/base/src/test/java/org/keycloak/testsuite/endpoint/client/ClientTemplateTest.java
index 25e287d..85f05e2 100644
--- a/testsuite/integration-arquillian/tests/base/src/test/java/org/keycloak/testsuite/endpoint/client/ClientTemplateTest.java
+++ b/testsuite/integration-arquillian/tests/base/src/test/java/org/keycloak/testsuite/endpoint/client/ClientTemplateTest.java
@@ -23,6 +23,7 @@ import java.util.HashSet;
 import java.util.List;
 import java.util.Set;
 
+import javax.ws.rs.BadRequestException;
 import javax.ws.rs.NotFoundException;
 import javax.ws.rs.core.Response;
 
@@ -35,6 +36,7 @@ import org.keycloak.models.AccountRoles;
 import org.keycloak.models.Constants;
 import org.keycloak.protocol.oidc.OIDCLoginProtocol;
 import org.keycloak.protocol.saml.SamlProtocol;
+import org.keycloak.representations.idm.ClientRepresentation;
 import org.keycloak.representations.idm.ClientTemplateRepresentation;
 import org.keycloak.representations.idm.ErrorRepresentation;
 import org.keycloak.representations.idm.MappingsRepresentation;
@@ -270,6 +272,40 @@ public class ClientTemplateTest extends AbstractClientTest {
     }
 
 
+    // KEYCLOAK-2844
+    @Test
+    public void testRemoveTemplateInUse() {
+        // Add client template
+        ClientTemplateRepresentation templateRep = new ClientTemplateRepresentation();
+        templateRep.setName("foo-template");
+        templateRep.setFullScopeAllowed(false);
+        String templateId = createTemplate(templateRep);
+
+        // Add client with the clientTemplate
+        ClientRepresentation clientRep = new ClientRepresentation();
+        clientRep.setClientId("bar-client");
+        clientRep.setName("bar-client");
+        clientRep.setRootUrl("foo");
+        clientRep.setProtocol("openid-connect");
+        clientRep.setClientTemplate("foo-template");
+        String clientDbId = createClient(clientRep);
+
+        // Can't remove clientTemplate
+        try {
+            clientTemplates().get(templateId).remove();
+        } catch (BadRequestException bre) {
+            ErrorRepresentation error = bre.getResponse().readEntity(ErrorRepresentation.class);
+            Assert.assertEquals("Cannot remove client template, it is currently in use", error.getErrorMessage());
+        }
+
+        // Remove client
+        testRealmResource().clients().get(clientDbId).remove();
+
+        // Can remove clientTemplate now
+        clientTemplates().get(templateId).remove();
+    }
+
+
     private ClientTemplatesResource clientTemplates() {
         return testRealmResource().clientTemplates();
     }