obelix74 commented on code in PR #3385: URL: https://github.com/apache/polaris/pull/3385#discussion_r2825523505
########## runtime/service/src/main/java/org/apache/polaris/service/persistence/MetricsPersistenceFactory.java: ########## @@ -0,0 +1,62 @@ +/* + * 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.persistence; + +import io.smallrye.common.annotation.Identifier; +import jakarta.enterprise.context.ApplicationScoped; +import jakarta.enterprise.inject.Any; +import jakarta.enterprise.inject.Instance; +import jakarta.inject.Inject; +import org.apache.polaris.core.persistence.metrics.MetricsPersistence; + +/** + * Factory for creating {@link MetricsPersistence} instances. + * + * <p>This factory is {@link ApplicationScoped} to resolve the configured {@link MetricsPersistence} + * implementation once at startup. The heavy CDI bean selection is performed once, and subsequent + * calls to {@link #create()} are lightweight operations that simply retrieve an instance from the + * already-selected implementation. + * + * <p>This pattern avoids resolving the bean selector on every request, improving performance for + * request-scoped {@link MetricsPersistence} beans. + */ +@ApplicationScoped +public class MetricsPersistenceFactory { + + private final Instance<MetricsPersistence> selectedImpl; + + @Inject + public MetricsPersistenceFactory( + MetricsPersistenceConfiguration config, + @Any Instance<MetricsPersistence> metricsPersistenceImpls) { + // Resolve the selector once at startup based on configuration + this.selectedImpl = metricsPersistenceImpls.select(Identifier.Literal.of(config.type())); + } + + /** + * Creates a {@link MetricsPersistence} instance from the configured implementation. + * + * <p>This is a lightweight operation since the implementation was already selected at startup. + * + * @return a MetricsPersistence instance + */ + public MetricsPersistence create() { + return selectedImpl.get(); Review Comment: I evaluated this and decided to keep MetricsPersistenceFactory. While JdbcMetricsPersistenceProducer now handles the heavy work efficiently, MetricsPersistenceFactory serves a different purpose - it handles configuration-based implementation selection (choosing between noop, relational-jdbc, etc. based on polaris.persistence.metrics.type). The factory resolves the CDI bean selector once at startup based on this configuration. Without it, we'd need a different mechanism to select which implementation to use. Let me know if you'd prefer a different approach. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
