/*
* Copyright © 2026 Dmitry Degrave
*
* Licensed 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.dnaerys.db;
import jakarta.annotation.PostConstruct;
import jakarta.annotation.PreDestroy;
import jakarta.enterprise.context.ApplicationScoped;
import org.jboss.logging.Logger;
import java.io.InputStream;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.StandardCopyOption;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.Statement;
@ApplicationScoped
public class DuckDBConnectionProducer {
private static final Logger LOG = Logger.getLogger(DuckDBConnectionProducer.class);
private static final String KGPE_RESOURCE = "kgpe.json";
private static final String TABLE_NAME = "sample_meta";
private Connection connection;
private Path tempJsonFile;
@PostConstruct
void init() {
try {
connection = DriverManager.getConnection("jdbc:duckdb:");
tempJsonFile = Files.createTempFile("kgpe-", ".json");
try (InputStream is = Thread.currentThread()
.getContextClassLoader()
.getResourceAsStream(KGPE_RESOURCE)) {
if (is == null) {
throw new RuntimeException("Resource not found: " + KGPE_RESOURCE);
}
Files.copy(is, tempJsonFile, StandardCopyOption.REPLACE_EXISTING);
}
try (Statement stmt = connection.createStatement()) {
stmt.execute(
"CREATE TABLE " + TABLE_NAME + " AS " +
"SELECT * FROM read_json_auto('" +
tempJsonFile.toAbsolutePath() + "')"
);
}
try (Statement stmt = connection.createStatement();
var rs = stmt.executeQuery("SELECT count(*) FROM " + TABLE_NAME)) {
rs.next();
LOG.infof("DuckDB initialized: loaded %d records into '%s'",
rs.getInt(1), TABLE_NAME);
}
} catch (Exception e) {
throw new RuntimeException("Failed to initialize DuckDB", e);
}
}
public Connection getConnection() {
return connection;
}
@PreDestroy
void cleanup() {
try {
if (connection != null && !connection.isClosed()) {
connection.close();
}
if (tempJsonFile != null) {
Files.deleteIfExists(tempJsonFile);
}
} catch (Exception e) {
LOG.warn("Error during DuckDB cleanup", e);
}
}
}
