Package ch.rswk.meta.engine

Class EngineUpdater

java.lang.Object

ch.rswk.meta.engine.EngineUpdater

public class EngineUpdater
extends Object

EngineUpdater executes tasks against two engine instances for importing/exporting and migrating service data. The current instance acts as the source of data and a new, pristine instance acts as a target for data. After one or more tasks are run without error, all data directories of the current instance are swapped with the data directories of the new instance.

Custom tasks can be injected by implementing EngineUpdater.UpdateTask. Built in tasks:

• EngineUpdater.CloneTask - Clones (re-index) all Lucene based data (FileService, MetaService, UserService) of the current instance to the new instance. Useful in case of schema changes or update to a new Lucene version
• EngineUpdater.JsonImportTask - Imports data from a JSON file to the new instance. Can also update or delete data. See EngineUpdater.JsonImportTaskConfig for options
• EngineUpdater.JsonExportTask - Exports selected data from the current instance to a JSON file. See EngineUpdater.JsonExportTaskConfig for options
• EngineUpdater.EngineImportTask - Imports selected data from a remote engine to the new instance. See EngineUpdater.EngineImportTaskConfig options

EngineUpdater.MetaUpdater and EngineUpdater.MetaUserUpdater instances can be injected to do data/schema migrations.

Important notes:

• Tasks are executed in the order they are provided to runTasks(String[], Function, Iterable)
• If any of the tasks returns true for skipIndexReplacement, the Lucene work directories of the current instance are not replaced with the new ones
• Replacement of Lucene work directories takes place, if every task returns false for skipIndexReplacement. If none of the tasks writes any Lucene data to the new instance, all data will be lost!
• To import data into an existing instance, run EngineUpdater.CloneTask followed by EngineUpdater.JsonImportTask. Or the other way around, if the new data should have precedence

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	EngineUpdater.AbstractUpdateTask
static class	EngineUpdater.CloneTask
static class	EngineUpdater.EngineImportTask
static final record	EngineUpdater.EngineImportTaskConfig
static class	EngineUpdater.JsonExportTask
static final record	EngineUpdater.JsonExportTaskConfig
static final record	EngineUpdater.JsonExportTaskResult
static class	EngineUpdater.JsonImportTask
static final record	EngineUpdater.JsonImportTaskConfig
static interface	EngineUpdater.MetaUpdater
static interface	EngineUpdater.MetaUserUpdater
static final record	EngineUpdater.UpdaterContext
static class	EngineUpdater.UpdaterServices
static final record	EngineUpdater.UpdaterServicesConfigs
static interface	EngineUpdater.UpdateTask
static class	EngineUpdater.UpdateTaskContext
static final record	EngineUpdater.UpdateTaskResult

Field Summary

Fields

Modifier and Type	Field	Description
private final EngineLauncher.EngineConfig	engineConfig
private static final org.slf4j.Logger	LOG
private final Set<EngineUpdater.MetaUpdater>	metaUpdaters
private final Set<EngineUpdater.UpdateTask>	tasks
private final Set<EngineUpdater.MetaUserUpdater>	userUpdaters

Constructor Summary

Constructors

Constructor	Description
EngineUpdater(EngineLauncher.EngineConfig engineConfig, Set<EngineUpdater.MetaUpdater> metaUpdaters, Set<EngineUpdater.UpdateTask> tasks, Set<EngineUpdater.MetaUserUpdater> userUpdaters)

Method Summary

Modifier and Type	Method	Description
private static void	replaceIndex(String indexDir, Path newIndexDir)
void	runTasks(String[] args, Function<EngineUpdater.UpdaterServicesConfigs,EngineUpdater.UpdaterServices> servicesSupplier, Iterable<String> taskIds)
private EngineUpdater.UpdaterServices	startUpNewServices(Path fileIndexDir, Path metaIndexDir, Function<EngineUpdater.UpdaterServicesConfigs,EngineUpdater.UpdaterServices> servicesSupplier, Path userIndexDir)
private static EngineUpdater.UpdaterServices	startUpOldServices(EngineLauncher.EngineConfig config, Function<EngineUpdater.UpdaterServicesConfigs,EngineUpdater.UpdaterServices> servicesSupplier)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

LOG

private static final org.slf4j.Logger LOG

engineConfig

private final EngineLauncher.EngineConfig engineConfig

metaUpdaters

private final Set<EngineUpdater.MetaUpdater> metaUpdaters

tasks

private final Set<EngineUpdater.UpdateTask> tasks

userUpdaters

private final Set<EngineUpdater.MetaUserUpdater> userUpdaters

Constructor Details

EngineUpdater

@Inject
public EngineUpdater(EngineLauncher.EngineConfig engineConfig,
 Set<EngineUpdater.MetaUpdater> metaUpdaters,
 Set<EngineUpdater.UpdateTask> tasks,
 Set<EngineUpdater.MetaUserUpdater> userUpdaters)

Method Details

runTasks

public void runTasks(String[] args,
 Function<EngineUpdater.UpdaterServicesConfigs,EngineUpdater.UpdaterServices> servicesSupplier,
 Iterable<String> taskIds)
              throws Exception

Throws:

Exception

startUpOldServices

private static EngineUpdater.UpdaterServices startUpOldServices(EngineLauncher.EngineConfig config,
 Function<EngineUpdater.UpdaterServicesConfigs,EngineUpdater.UpdaterServices> servicesSupplier)

startUpNewServices

private EngineUpdater.UpdaterServices startUpNewServices(Path fileIndexDir,
 Path metaIndexDir,
 Function<EngineUpdater.UpdaterServicesConfigs,EngineUpdater.UpdaterServices> servicesSupplier,
 Path userIndexDir)

replaceIndex

private static void replaceIndex(String indexDir,
 Path newIndexDir)
                          throws IOException

Throws:

IOException