Package io.debezium.transforms

Class ScriptingTransformation<R extends org.apache.kafka.connect.connector.ConnectRecord<R>>

java.lang.Object

io.debezium.transforms.ScriptingTransformation<R>

Type Parameters:

R - the subtype of ConnectRecord on which this transformation will operate

All Implemented Interfaces:

Closeable, AutoCloseable, org.apache.kafka.common.Configurable, org.apache.kafka.connect.transforms.Transformation<R>

Direct Known Subclasses:

ContentBasedRouter, Filter

@Incubating
public abstract class ScriptingTransformation<R extends org.apache.kafka.connect.connector.ConnectRecord<R>>
extends Object
implements org.apache.kafka.connect.transforms.Transformation<R>

This is a base class for any SMT using scripting languages. Current implementation supports only JSR223 scripting languages.

The SMT will instantiate an scripting engine encapsulated in Engine interface in configure phase. It will try to pre-parse the expression if it is allowed by the engine and than the expression is evaluated for every record incoming.

The engine will extract key, value and its schemas and will inject them as variables into the engine. The mapping is unique for each expression language.

Author:

Jiri Pechanec

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static enum	ScriptingTransformation.NullHandling

Field Summary

Fields

Modifier and Type	Field	Description
protected Engine	engine
private static final String	GRAAL_JS_ENGINE
private static final String	JAVAX_SCRIPT_ENGINE_PREFIX
static final Field	LANGUAGE
private final org.slf4j.Logger	LOGGER
static final Field	NULL_HANDLING
private ScriptingTransformation.NullHandling	nullHandling
private static final Field	TOPIC_REGEX
private Pattern	topicPattern

Constructor Summary

Constructors

Constructor	Description
ScriptingTransformation()

Method Summary

Modifier and Type	Method	Description
R	apply(R record)
void	close()
org.apache.kafka.common.config.ConfigDef	config()
void	configure(Map<String,?> configs)
protected abstract R	doApply(R record)
protected abstract Field	expressionField()

Methods inherited from class java.lang.Object

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

Field Details

LOGGER

private final org.slf4j.Logger LOGGER

JAVAX_SCRIPT_ENGINE_PREFIX

private static final String JAVAX_SCRIPT_ENGINE_PREFIX

See Also:

• Constant Field Values

GRAAL_JS_ENGINE

private static final String GRAAL_JS_ENGINE

See Also:

• Constant Field Values

TOPIC_REGEX

private static final Field TOPIC_REGEX

LANGUAGE

public static final Field LANGUAGE

NULL_HANDLING

public static final Field NULL_HANDLING

engine

protected Engine engine

nullHandling

private ScriptingTransformation.NullHandling nullHandling

topicPattern

private Pattern topicPattern

Constructor Details

ScriptingTransformation

public ScriptingTransformation()

Method Details

configure

public void configure(Map<String,?> configs)

Specified by:

configure in interface org.apache.kafka.common.Configurable

apply

public R apply(R record)

Specified by:

apply in interface org.apache.kafka.connect.transforms.Transformation<R extends org.apache.kafka.connect.connector.ConnectRecord<R>>

doApply

protected abstract R doApply(R record)

expressionField

protected abstract Field expressionField()

config

public org.apache.kafka.common.config.ConfigDef config()

Specified by:

config in interface org.apache.kafka.connect.transforms.Transformation<R extends org.apache.kafka.connect.connector.ConnectRecord<R>>

close

public void close()

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Specified by:

close in interface org.apache.kafka.connect.transforms.Transformation<R extends org.apache.kafka.connect.connector.ConnectRecord<R>>