WIP: refactoring

src/main/java/caosdb/server/CaosDBServer.java

@@ -27,6 +27,7 @@ import caosdb.server.accessControl.OneTimeTokenRealm;
 import caosdb.server.accessControl.Principal;
 import caosdb.server.accessControl.SessionToken;
 import caosdb.server.accessControl.SessionTokenRealm;
+import caosdb.server.converter.misc.HttpStatusConverter;
 import caosdb.server.converter.misc.MultipartContainerConverter;
 import caosdb.server.converter.xml.EntityXMLConverterHelper;
 import caosdb.server.database.BackendTransaction;
@@ -100,6 +101,7 @@ import org.restlet.data.Reference;
 import org.restlet.data.ServerInfo;
 import org.restlet.data.Status;
 import org.restlet.engine.Engine;
+import org.restlet.engine.converter.DefaultConverter;
 import org.restlet.routing.Route;
 import org.restlet.routing.Router;
 import org.restlet.routing.Template;
@@ -345,8 +347,13 @@ public class CaosDBServer extends Application {
 
       init.release();
 
-      Engine.getInstance().getRegisteredConverters().add(new EntityXMLConverterHelper());
+      Engine.getInstance().getRegisteredConverters().clear();
+      Engine.getInstance().getRegisteredConverters().add(new DefaultConverter());
+      // add XML Converters
+      EntityXMLConverterHelper xmlConverter = new EntityXMLConverterHelper();
+      Engine.getInstance().getRegisteredConverters().add(xmlConverter);
       Engine.getInstance().getRegisteredConverters().add(new MultipartContainerConverter());
+      Engine.getInstance().getRegisteredConverters().add(new HttpStatusConverter(xmlConverter));
 
       if (INSECURE) {
         runHTTPServer(port_http, initialConnections, maxTotalConnections);

src/main/java/caosdb/server/converter/misc/CaosDBStatusService.java

+package caosdb.server.converter.misc;
+
+import org.restlet.service.StatusService;
+
+public class CaosDBStatusService extends StatusService {
+
+}

src/main/java/caosdb/server/converter/misc/HttpStatusConverter.java

+package caosdb.server.converter.misc;
+
+import java.io.IOException;
+import java.util.List;
+import org.apache.shiro.SecurityUtils;
+import org.apache.shiro.subject.Subject;
+import org.restlet.data.Status;
+import org.restlet.engine.application.StatusInfo;
+import org.restlet.engine.converter.ConverterHelper;
+import org.restlet.engine.resource.VariantInfo;
+import org.restlet.representation.Representation;
+import org.restlet.representation.Variant;
+import org.restlet.resource.Resource;
+import caosdb.server.entity.Message;
+import caosdb.server.entity.container.TransactionContainer;
+import caosdb.server.utils.ServerMessages;
+
+public class HttpStatusConverter extends ConverterHelper {
+
+  private AbstractContainerHelper containerConverter;
+  private TransactionContainer dummyContainer;
+
+  public HttpStatusConverter(AbstractContainerHelper converter) {
+    this.containerConverter = converter;
+    this.dummyContainer = new TransactionContainer();
+  }
+
+  @Override
+  public List<Class<?>> getObjectClasses(Variant source) {
+    // the server does not need this.
+    return null;
+  }
+
+  @Override
+  public List<VariantInfo> getVariants(Class<?> source) throws IOException {
+    if (isCompatible(source)) {
+      return containerConverter.getVariants(TransactionContainer.class);
+    }
+    return null;
+  }
+
+  private boolean isCompatible(Class<?> source) {
+    return source != null && source.isAssignableFrom(StatusInfo.class);
+  }
+
+  @Override
+  public float score(Object source, Variant target, Resource resource) {
+    return containerConverter.score(dummyContainer, target, resource);
+  }
+
+  @Override
+  public <T> float score(Representation source, Class<T> target, Resource resource) {
+    // no implementation for this direction of the conversion
+    return -1.0F;
+  }
+
+  @Override
+  public <T> T toObject(Representation source, Class<T> target, Resource resource)
+      throws IOException {
+    // the server does not need this.
+    return null;
+  }
+
+  @Override
+  public Representation toRepresentation(Object source, Variant target, Resource resource)
+      throws IOException {
+    Representation result = null;
+
+    if (source != null && StatusInfo.class.isAssignableFrom(source.getClass())) {
+      StatusInfo status = (StatusInfo) source;
+      result = toJdomRepresentation(status, target, resource);
+    }
+
+    return result;
+  }
+
+  private Representation toJdomRepresentation(StatusInfo status, Variant target, Resource resource)
+      throws IOException {
+    Subject owner = SecurityUtils.getSubject();
+    Long timestamp = null;
+    String requestId = null;
+    if (resource != null) {
+      timestamp = resource.getRequest().getDate().getTime();
+      requestId = resource.getRequestAttributes().get("SRID").toString();
+    }
+
+    TransactionContainer t = new TransactionContainer(owner, timestamp, requestId);
+    if (status.getCode() == 500) {
+      t.addMessage(ServerMessages.UNKNOWN_ERROR(requestId));
+    } else {
+      t.addMessage(new Message((Status.valueOf(status.getCode()).isError() ? "Error" : "Info"),
+          status.getCode(), status.getReasonPhrase(), status.getDescription()));
+    }
+    return containerConverter.toRepresentation(t, target, resource);
+  }
+}

src/main/java/caosdb/server/converter/xml/MessageConverter.java

+package caosdb.server.converter.xml;
+
+import caosdb.server.converter.misc.AbstractContainerHelper;
+import caosdb.server.entity.Message;
+import caosdb.server.entity.container.TransactionContainer;
+import java.io.IOException;
+import java.util.List;
+import org.restlet.engine.converter.ConverterHelper;
+import org.restlet.engine.resource.VariantInfo;
+import org.restlet.representation.Representation;
+import org.restlet.representation.Variant;
+import org.restlet.resource.Resource;
+
+public class MessageConverter extends ConverterHelper {
+
+  private final AbstractContainerHelper containerConverter;
+
+  public MessageConverter(AbstractContainerHelper containerConverter) {
+    this.containerConverter = containerConverter;
+  }
+
+  @Override
+  public List<Class<?>> getObjectClasses(Variant source) {
+    // no conversion to message needed.
+    return null;
+  }
+
+  @Override
+  public List<VariantInfo> getVariants(Class<?> source) throws IOException {
+    // TODO Auto-generated method stub
+    return null;
+  }
+
+  @Override
+  public float score(Object source, Variant target, Resource resource) {
+    if (source instanceof Message) {
+      return getContainerConverter().score(wrapp(source), target, resource);
+    }
+    // TODO Auto-generated method stub
+    return -1.0F;
+  }
+
+  private TransactionContainer wrapp(Object source) {
+    return null;
+  }
+
+  @Override
+  public <T> float score(Representation source, Class<T> target, Resource resource) {
+    // TODO Auto-generated method stub
+    return -1.0F;
+  }
+
+  @Override
+  public <T> T toObject(Representation source, Class<T> target, Resource resource)
+      throws IOException {
+    // no implementation needed.
+    return null;
+  }
+
+  @Override
+  public Representation toRepresentation(Object source, Variant target, Resource resource)
+      throws IOException {
+    // TODO Auto-generated method stub
+    return null;
+  }
+
+  public AbstractContainerHelper getContainerConverter() {
+    return containerConverter;
+  }
+}

src/main/java/caosdb/server/entity/Message.java

@@ -22,8 +22,9 @@
  */
 package caosdb.server.entity;
 
-import caosdb.server.entity.xml.ToElementable;
 import org.jdom2.Element;
+import org.restlet.data.Status;
+import caosdb.server.entity.xml.ToElementable;
 
 public class Message extends Exception implements Comparable<Message>, ToElementable {
 
@@ -40,6 +41,10 @@ public class Message extends Exception implements Comparable<Message>, ToElement
     Info
   };
   
+  public Message(Status status) {
+    this(status.isError()? "Error" : "Info", status.getCode(), status.getReasonPhrase(), status.getDescription());
+  }
+
   @Override
   public int hashCode() {
     return toString().hashCode();

src/main/java/caosdb/server/resource/AbstractCaosDBServerResource.java

@@ -23,11 +23,18 @@
  */
 package caosdb.server.resource;
 
-import caosdb.server.utils.WebinterfaceUtils;
+import java.io.IOException;
+import java.util.List;
+import java.util.logging.Level;
 import org.apache.shiro.SecurityUtils;
 import org.apache.shiro.subject.Subject;
 import org.restlet.data.MediaType;
+import org.restlet.data.Status;
+import org.restlet.engine.application.StatusInfo;
+import org.restlet.representation.Representation;
+import org.restlet.representation.Variant;
 import org.restlet.resource.ServerResource;
+import caosdb.server.utils.WebinterfaceUtils;
 
 /**
  * Base class for all CaosDB Server Resources.
@@ -86,4 +93,38 @@ public abstract class AbstractCaosDBServerResource extends ServerResource {
   public final String getSRID() {
     return getRequest().getAttributes().get("SRID").toString();
   }
+  
+  /*
+   * Stolen from Restlet and adapted to our needs.
+   */
+  @Override
+  protected void doCatch(Throwable throwable) {
+        Level level = Level.INFO;
+        Status status = getStatusService().toStatus(throwable, this);
+
+        if (status.isServerError()) {
+            level = Level.SEVERE;
+        } else if (status.isConnectorError()) {
+            level = Level.INFO;
+        } else if (status.isClientError()) {
+            level = Level.FINE;
+        }
+
+        getLogger().log(level, "Exception or error caught in server resource",
+                throwable);
+
+        if (getResponse() != null) {
+          getResponse().setStatus(status);
+
+            List<Variant> variants = getVariants(getMethod());
+            Variant preferredVariant = getPreferredVariant(variants);
+            try {
+              Representation errorEntity;
+              errorEntity = toRepresentation(new StatusInfo(status), preferredVariant);
+              getResponse().setEntity(errorEntity);
+            } catch (IOException e) {
+              getLogger().log(Level.SEVERE, "Exception during serialization of another error.", e);
+            }
+        }
+  }
 }