How to run Neo4j embedded with Apoc installed. Using Java 23 preview to avoid the ceremony of an empty class holding main (See JEP 477).

Neo4jWithApoc.java

///usr/bin/env jbang "$0" "$@" ; exit $?
//JAVA 23
//PREVIEW
//DEPS org.neo4j:neo4j:2025.01.0
//DEPS org.neo4j.procedure:apoc-common:2025.01.0
//DEPS org.neo4j.procedure:apoc-core:2025.01.0

import java.nio.file.Files;
import java.nio.file.Path;
import java.util.Map;

import org.neo4j.configuration.GraphDatabaseSettings;
import org.neo4j.dbms.api.DatabaseManagementServiceBuilder;
import org.neo4j.kernel.internal.GraphDatabaseAPI;

import apoc.ApocConfig;
import apoc.CoreApocGlobalComponents;

void main() throws Exception {

	// Most non brittle solution
	// Create home dir
	var neo4jHome = Files.createTempDirectory("neo4j");
	// Create conf dir and an apoc.conf file
	var conf = Files.createDirectory(neo4jHome.resolve("conf"));
	var apocConf = Files.createFile(conf.resolve(Path.of("apoc.conf")));
	// Set your settings
	Files.writeString(apocConf, """
		apoc.trigger.enabled=true
		apoc.trigger.refresh=23
		"""
	);

	// If the above approach does not work for you, use sys variables (or env, if you can modify that)
	System.setProperty("apoc.export.file.enabled", "true");

	var dbms = new DatabaseManagementServiceBuilder(neo4jHome)
		// This is only for Neo4j.conf, and even if you use APOC settings in there, it won't be used
		// (It also won't let you without server.config.strict_validation.enabled=false)
		// .loadPropertiesFromFile(apocConf)
		//
		// We must point the service loader to the actual plugin jar, otherwise things won't get loaded properly
		.setConfig(GraphDatabaseSettings.plugin_dir,
			Path.of(CoreApocGlobalComponents.class.getProtectionDomain().getCodeSource().getLocation().toURI()).getParent())
		.build();
	var db = dbms.database("neo4j");
	var version = db.executeTransactionally("RETURN apoc.version() AS version", Map.of(), r -> r.next().get("version"));

	System.out.println("APOC version: " + version);

	// You could in theory also modify the apoc config object, but that feels 100% brittle
	var config = ((GraphDatabaseAPI) db).getDependencyResolver().resolveDependency(ApocConfig.class).getConfig();
	System.out.println("Trigger enabled: " + config.getBoolean(ApocConfig.APOC_TRIGGER_ENABLED));
	System.out.println("File export enabled: " + config.getBoolean(ApocConfig.APOC_EXPORT_FILE_ENABLED));
	dbms.shutdown();
}