| /* |
| * 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.nifi.serialization; |
| |
| import org.apache.nifi.controller.ControllerService; |
| import org.apache.nifi.serialization.record.RecordSchema; |
| |
| import java.util.Optional; |
| |
| public interface RecordSchemaCacheService extends ControllerService { |
| public static final String CACHE_IDENTIFIER_ATTRIBUTE = "schema.cache.identifier"; |
| |
| /** |
| * Updates the cache to include the given Record Schema and returns an identifier |
| * for the Schema. If the schema already exists in the cache, the existing identifier |
| * is returned. Otherwise, the schema is added to the cache and a new identifier is |
| * created and returned. This identifier can then be used to retrieve the Record Schema |
| * via the {@link #getSchema(String)} method |
| * |
| * @param schema the schema to cache |
| * @return a unique identifier for the schema |
| */ |
| String cacheSchema(RecordSchema schema); |
| |
| /** |
| * Returns the Schema with the given identifier, if it can be found in the cache. |
| * Note that the cache may choose to evict schemas for any number of reasons and, as such, |
| * the service may return an empty Optional even immediately after the Schema is cached |
| * via the {@link #cacheSchema(RecordSchema)}. |
| * |
| * @param schemaIdentifier the identifier of the schema |
| * @return an Optional holding the Record Schema with the given identifier, if it can be found, |
| * or an empty Optional if the schema cannot be found |
| */ |
| Optional<RecordSchema> getSchema(String schemaIdentifier); |
| |
| } |