When a grant already exists, return the appropriate response

extension/persistence/eclipselink/src/main/java/org/apache/polaris/extension/persistence/impl/eclipselink/PolarisEclipseLinkMetaStoreSessionImpl.java

@@ -27,13 +27,15 @@
 import jakarta.persistence.EntityTransaction;
 import jakarta.persistence.OptimisticLockException;
 import jakarta.persistence.Persistence;
+import jakarta.persistence.PersistenceException;
 import java.io.File;
 import java.io.IOException;
 import java.io.InputStream;
 import java.net.URL;
 import java.net.URLClassLoader;
 import java.util.HashMap;
 import java.util.List;
+import java.util.Locale;
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.function.Function;
@@ -58,6 +60,7 @@
 import org.apache.polaris.core.entity.PolarisEntityType;
 import org.apache.polaris.core.entity.PolarisGrantRecord;
 import org.apache.polaris.core.entity.PolarisPrincipalSecrets;
+import org.apache.polaris.core.exceptions.AlreadyExistsException;
 import org.apache.polaris.core.persistence.PolarisMetaStoreManagerImpl;
 import org.apache.polaris.core.persistence.PolarisMetaStoreSession;
 import org.apache.polaris.core.persistence.RetryOnConcurrencyException;
@@ -261,6 +264,12 @@ public <T> T runInTransaction(
       } finally {
         localSession.remove();
       }
+    } catch (PersistenceException e) {
+      if (e.toString().toLowerCase(Locale.ROOT).contains("duplicate key")) {
+        throw new AlreadyExistsException("Duplicate key error when persisting entity", e);
+      } else {
+        throw e;
+      }
     }
   }
 

polaris-core/src/main/java/org/apache/polaris/core/exceptions/AlreadyExistsException.java

@@ -0,0 +1,33 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package org.apache.polaris.core.exceptions;
+
+/**
+ * A {@link PolarisException} implementation for when Polaris is unable to create an entity that
+ * already exists.
+ */
+public class AlreadyExistsException extends PolarisException {
+  public AlreadyExistsException(String message) {
+    super(message);
+  }
+
+  public AlreadyExistsException(String message, Throwable cause) {
+    super(message, cause);
+  }
+}

polaris-core/src/main/java/org/apache/polaris/core/exceptions/PolarisException.java

@@ -0,0 +1,35 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package org.apache.polaris.core.exceptions;
+
+/**
+ * Base class for Polaris-specific runtime exceptions.
+ *
+ * <p>All custom exceptions in Polaris should extend this class to provide specific error details.
+ */
+public abstract class PolarisException extends RuntimeException {
+
+  public PolarisException(String message) {
+    super(message);
+  }
+
+  public PolarisException(String message, Throwable cause) {
+    super(message, cause);
+  }
+}

polaris-service/src/main/java/org/apache/polaris/service/PolarisApplication.java

@@ -100,6 +100,10 @@
 import org.apache.polaris.service.context.CallContextResolver;
 import org.apache.polaris.service.context.PolarisCallContextCatalogFactory;
 import org.apache.polaris.service.context.RealmContextResolver;
+import org.apache.polaris.service.exception.IcebergExceptionMapper;
+import org.apache.polaris.service.exception.IcebergJerseyViolationExceptionMapper;
+import org.apache.polaris.service.exception.IcebergJsonProcessingExceptionMapper;
+import org.apache.polaris.service.exception.PolarisExceptionMapper;
 import org.apache.polaris.service.persistence.InMemoryPolarisMetaStoreManagerFactory;
 import org.apache.polaris.service.ratelimiter.RateLimiterFilter;
 import org.apache.polaris.service.storage.PolarisStorageIntegrationProviderImpl;
@@ -277,6 +281,7 @@ public void run(PolarisApplicationConfig configuration, Environment environment)
     }
     environment.jersey().register(new IcebergRestOAuth2Api(oauth2Service));
     environment.jersey().register(new IcebergExceptionMapper());
+    environment.jersey().register(new PolarisExceptionMapper());
     PolarisServiceImpl polarisService = new PolarisServiceImpl(entityManagerFactory, authorizer);
     environment.jersey().register(new PolarisCatalogsApi(polarisService));
     environment.jersey().register(new PolarisPrincipalsApi(polarisService));

polaris-service/src/main/java/org/apache/polaris/service/IcebergExceptionMapper.java → polaris-service/src/main/java/org/apache/polaris/service/exception/IcebergExceptionMapper.java

@@ -16,7 +16,7 @@
  * specific language governing permissions and limitations
  * under the License.
  */
-package org.apache.polaris.service;
+package org.apache.polaris.service.exception;
 
 import jakarta.ws.rs.WebApplicationException;
 import jakarta.ws.rs.core.MediaType;

polaris-service/src/main/java/org/apache/polaris/service/IcebergJerseyViolationExceptionMapper.java → polaris-service/src/main/java/org/apache/polaris/service/exception/IcebergJerseyViolationExceptionMapper.java

@@ -16,7 +16,7 @@
  * specific language governing permissions and limitations
  * under the License.
  */
-package org.apache.polaris.service;
+package org.apache.polaris.service.exception;
 
 import io.dropwizard.jersey.validation.JerseyViolationException;
 import jakarta.ws.rs.core.MediaType;

polaris-service/src/main/java/org/apache/polaris/service/IcebergJsonProcessingExceptionMapper.java → polaris-service/src/main/java/org/apache/polaris/service/exception/IcebergJsonProcessingExceptionMapper.java

@@ -16,7 +16,7 @@
  * specific language governing permissions and limitations
  * under the License.
  */
-package org.apache.polaris.service;
+package org.apache.polaris.service.exception;
 
 import com.fasterxml.jackson.core.JsonGenerationException;
 import com.fasterxml.jackson.core.JsonParseException;

polaris-service/src/main/java/org/apache/polaris/service/exception/PolarisExceptionMapper.java

@@ -0,0 +1,58 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package org.apache.polaris.service.exception;
+
+import jakarta.ws.rs.core.MediaType;
+import jakarta.ws.rs.core.Response;
+import jakarta.ws.rs.ext.ExceptionMapper;
+import jakarta.ws.rs.ext.Provider;
+import org.apache.iceberg.rest.responses.ErrorResponse;
+import org.apache.polaris.core.exceptions.AlreadyExistsException;
+import org.apache.polaris.core.exceptions.PolarisException;
+
+/**
+ * An {@link ExceptionMapper} implementation for {@link PolarisException}s modeled after {@link
+ * IcebergExceptionMapper}
+ */
+@Provider
+public class PolarisExceptionMapper implements ExceptionMapper<PolarisException> {
+
+  private Response.Status getStatus(PolarisException exception) {
+    if (exception instanceof AlreadyExistsException) {
+      return Response.Status.CONFLICT;
+    } else {
+      return Response.Status.INTERNAL_SERVER_ERROR;
+    }
+  }
+
+  @Override
+  public Response toResponse(PolarisException exception) {
+    Response.Status status = getStatus(exception);
+    ErrorResponse errorResponse =
+        ErrorResponse.builder()
+            .responseCode(status.getStatusCode())
+            .withType(exception.getClass().getSimpleName())
+            .withMessage(exception.getMessage())
+            .build();
+    return Response.status(status)
+        .entity(errorResponse)
+        .type(MediaType.APPLICATION_JSON_TYPE)
+        .build();
+  }
+}