org.apache.kafka.streams.scala.StreamsBuilder.scala Maven / Gradle / Ivy
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* 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.kafka.streams.scala
import java.util.Properties
import java.util.regex.Pattern
import org.apache.kafka.streams.kstream.GlobalKTable
import org.apache.kafka.streams.processor.{ProcessorSupplier, StateStore}
import org.apache.kafka.streams.state.StoreBuilder
import org.apache.kafka.streams.{StreamsBuilder => StreamsBuilderJ, Topology}
import org.apache.kafka.streams.scala.kstream.{Consumed, KStream, KTable, Materialized}
import scala.jdk.CollectionConverters._
/**
* Wraps the Java class StreamsBuilder and delegates method calls to the underlying Java object.
*/
class StreamsBuilder(inner: StreamsBuilderJ = new StreamsBuilderJ) {
/**
* Create a [[kstream.KStream]] from the specified topic.
*
* The `implicit Consumed` instance provides the values of `auto.offset.reset` strategy, `TimestampExtractor`,
* key and value deserializers etc. If the implicit is not found in scope, compiler error will result.
*
* A convenient alternative is to have the necessary implicit serdes in scope, which will be implicitly
* converted to generate an instance of `Consumed`. @see [[ImplicitConversions]].
* {{{
* // Brings all implicit conversions in scope
* import ImplicitConversions._
*
* // Bring implicit default serdes in scope
* import Serdes._
*
* val builder = new StreamsBuilder()
*
* // stream function gets the implicit Consumed which is constructed automatically
* // from the serdes through the implicits in ImplicitConversions#consumedFromSerde
* val userClicksStream: KStream[String, Long] = builder.stream(userClicksTopic)
* }}}
*
* @param topic the topic name
* @return a [[kstream.KStream]] for the specified topic
*/
def stream[K, V](topic: String)(implicit consumed: Consumed[K, V]): KStream[K, V] =
new KStream(inner.stream[K, V](topic, consumed))
/**
* Create a [[kstream.KStream]] from the specified topics.
*
* @param topics the topic names
* @return a [[kstream.KStream]] for the specified topics
* @see #stream(String)
* @see `org.apache.kafka.streams.StreamsBuilder#stream`
*/
def stream[K, V](topics: Set[String])(implicit consumed: Consumed[K, V]): KStream[K, V] =
new KStream(inner.stream[K, V](topics.asJava, consumed))
/**
* Create a [[kstream.KStream]] from the specified topic pattern.
*
* @param topicPattern the topic name pattern
* @return a [[kstream.KStream]] for the specified topics
* @see #stream(String)
* @see `org.apache.kafka.streams.StreamsBuilder#stream`
*/
def stream[K, V](topicPattern: Pattern)(implicit consumed: Consumed[K, V]): KStream[K, V] =
new KStream(inner.stream[K, V](topicPattern, consumed))
/**
* Create a [[kstream.KTable]] from the specified topic.
*
* The `implicit Consumed` instance provides the values of `auto.offset.reset` strategy, `TimestampExtractor`,
* key and value deserializers etc. If the implicit is not found in scope, compiler error will result.
*
* A convenient alternative is to have the necessary implicit serdes in scope, which will be implicitly
* converted to generate an instance of `Consumed`. @see [[ImplicitConversions]].
* {{{
* // Brings all implicit conversions in scope
* import ImplicitConversions._
*
* // Bring implicit default serdes in scope
* import Serdes._
*
* val builder = new StreamsBuilder()
*
* // stream function gets the implicit Consumed which is constructed automatically
* // from the serdes through the implicits in ImplicitConversions#consumedFromSerde
* val userClicksStream: KTable[String, Long] = builder.table(userClicksTopic)
* }}}
*
* @param topic the topic name
* @return a [[kstream.KTable]] for the specified topic
* @see `org.apache.kafka.streams.StreamsBuilder#table`
*/
def table[K, V](topic: String)(implicit consumed: Consumed[K, V]): KTable[K, V] =
new KTable(inner.table[K, V](topic, consumed))
/**
* Create a [[kstream.KTable]] from the specified topic.
*
* @param topic the topic name
* @param materialized the instance of `Materialized` used to materialize a state store
* @return a [[kstream.KTable]] for the specified topic
* @see #table(String)
* @see `org.apache.kafka.streams.StreamsBuilder#table`
*/
def table[K, V](topic: String, materialized: Materialized[K, V, ByteArrayKeyValueStore])(implicit
consumed: Consumed[K, V]
): KTable[K, V] =
new KTable(inner.table[K, V](topic, consumed, materialized))
/**
* Create a `GlobalKTable` from the specified topic. The serializers from the implicit `Consumed`
* instance will be used. Input records with `null` key will be dropped.
*
* @param topic the topic name
* @return a `GlobalKTable` for the specified topic
* @see `org.apache.kafka.streams.StreamsBuilder#globalTable`
*/
def globalTable[K, V](topic: String)(implicit consumed: Consumed[K, V]): GlobalKTable[K, V] =
inner.globalTable(topic, consumed)
/**
* Create a `GlobalKTable` from the specified topic. The resulting `GlobalKTable` will be materialized
* in a local `KeyValueStore` configured with the provided instance of `Materialized`. The serializers
* from the implicit `Consumed` instance will be used.
*
* @param topic the topic name
* @param materialized the instance of `Materialized` used to materialize a state store
* @return a `GlobalKTable` for the specified topic
* @see `org.apache.kafka.streams.StreamsBuilder#globalTable`
*/
def globalTable[K, V](topic: String, materialized: Materialized[K, V, ByteArrayKeyValueStore])(implicit
consumed: Consumed[K, V]
): GlobalKTable[K, V] =
inner.globalTable(topic, consumed, materialized)
/**
* Adds a state store to the underlying `Topology`. The store must still be "connected" to a `Processor`,
* `Transformer`, or `ValueTransformer` before it can be used.
*
* It is required to connect state stores to `Processor`, `Transformer`, or `ValueTransformer` before they can be used.
*
* @param builder the builder used to obtain this state store `StateStore` instance
* @return the underlying Java abstraction `StreamsBuilder` after adding the `StateStore`
* @throws org.apache.kafka.streams.errors.TopologyException if state store supplier is already added
* @see `org.apache.kafka.streams.StreamsBuilder#addStateStore`
*/
def addStateStore(builder: StoreBuilder[_ <: StateStore]): StreamsBuilderJ = inner.addStateStore(builder)
/**
* Adds a global `StateStore` to the topology. Global stores should not be added to `Processor`, `Transformer`,
* or `ValueTransformer` (in contrast to regular stores).
*
* It is not required to connect a global store to `Processor`, `Transformer`, or `ValueTransformer`;
* those have read-only access to all global stores by default.
*
* @see `org.apache.kafka.streams.StreamsBuilder#addGlobalStore`
*/
@deprecated(
"Use #addGlobalStore(StoreBuilder, String, Consumed, org.apache.kafka.streams.processor.api.ProcessorSupplier) instead.",
"2.7.0"
)
def addGlobalStore[K, V](
storeBuilder: StoreBuilder[_ <: StateStore],
topic: String,
consumed: Consumed[K, V],
stateUpdateSupplier: ProcessorSupplier[K, V]
): StreamsBuilderJ =
inner.addGlobalStore(storeBuilder, topic, consumed, stateUpdateSupplier)
/**
* Adds a global `StateStore` to the topology. Global stores should not be added to `Processor`, `Transformer`,
* or `ValueTransformer` (in contrast to regular stores).
*
* It is not required to connect a global store to `Processor`, `Transformer`, or `ValueTransformer`;
* those have read-only access to all global stores by default.
*
* @see `org.apache.kafka.streams.StreamsBuilder#addGlobalStore`
*/
def addGlobalStore[K, V](
storeBuilder: StoreBuilder[_ <: StateStore],
topic: String,
consumed: Consumed[K, V],
stateUpdateSupplier: org.apache.kafka.streams.processor.api.ProcessorSupplier[K, V, Void, Void]
): StreamsBuilderJ =
inner.addGlobalStore(storeBuilder, topic, consumed, stateUpdateSupplier)
def build(): Topology = inner.build()
/**
* Returns the `Topology` that represents the specified processing logic and accepts
* a `Properties` instance used to indicate whether to optimize topology or not.
*
* @param props the `Properties` used for building possibly optimized topology
* @return the `Topology` that represents the specified processing logic
* @see `org.apache.kafka.streams.StreamsBuilder#build`
*/
def build(props: Properties): Topology = inner.build(props)
}