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Can one Kafka consumer subscribe to multiple topics?

Can one Kafka consumer subscribe to multiple topics?

Apache Kafka allows a single consumer to subscribe to multiple topics at the same time and process both in a combined stream of records.

What is key serializer and value serializer in Kafka?

The key. serializer and value. serializer instruct how to turn the key and value objects the user provides with their ProducerRecord into bytes. You can use the included ByteArraySerializer or StringSerializer for simple string or byte types.

What is the difference between consumer and consumer group in Kafka?

Kafka consumers belonging to the same consumer group share a group id. The consumers in a group then divides the topic partitions as fairly amongst themselves as possible by establishing that each partition is only consumed by a single consumer from the group. The messages are broadcast to all consumer groups.

How to implement custom value Serializer for Kafka?

So one thing is clear that Kafka depends on Serializer and Deserializer so that Producer and Consumer both know how to communicate and understand the messages. Now we will see how we can implement our own custom value serializer and deserializer to send and receive custom java objects from Kafka topics.

How to create consumer and producer in Kafka?

1. First will create User POJO class. 2. Create User serializer class by extending Kafka Serializer 3. Create User deserializer class by extending Kafka Deserializer 4. Create a Kafka consumer and use UserDeserializer for “value.deserializer” property. 5. Create a Kafka producer and use UserSerializer for “value.serializer” property. 6.

Which is the opposite of serialization in Apache Kafka?

Although, Apache Kafka stores as well as transmit these bytes of arrays in its queue. Whereas, the opposite of Serialization is Deserialization. Here we convert bytes of arrays into the data type we desire. However, make sure Kafka offers serializers and deserializers for only a few data types, such as 3.

Can you send different data types to Kafka topics?

You can send messages with different data types to kafka topics. The Kafka deals with messages or records in the form of byte array. If you have observed, both KafkaProducer and KafkaConsumer needs key and value serializer. The default configuration for Producer

How to use custom serializer and deserializer in Kafka?

Lets say we want to send a custom object as the kafka value type and we need to push this custom object into the kafka topic so we need to implement our custom serializer and deserializer and also a custom encoder to read the data in spark streaming.

1. First will create User POJO class. 2. Create User serializer class by extending Kafka Serializer 3. Create User deserializer class by extending Kafka Deserializer 4. Create a Kafka consumer and use UserDeserializer for “value.deserializer” property. 5. Create a Kafka producer and use UserSerializer for “value.serializer” property. 6.

Although, Apache Kafka stores as well as transmit these bytes of arrays in its queue. Whereas, the opposite of Serialization is Deserialization. Here we convert bytes of arrays into the data type we desire. However, make sure Kafka offers serializers and deserializers for only a few data types, such as 3.

Can a deserializer be used in a serializer?

Starting with version 2.1, type information can be conveyed in record Headers , allowing the handling of multiple types. In addition, the serializer/deserializer can be configured using Kafka Properties.