The magical operation method of Kafka interceptor

Preface

On the stage of messaging, the interceptor is like a group of patron saints, responsible for defending the flow of information. These gatekeepers play a vital role in the system, creating miracles for data security and processing. This article will take you into this magical realm and explore the magic of interceptors.

The basic concept of interceptor

In Kafka, Interceptors are a mechanism that allows you to perform some customization operations before the message is sent to Kafka by the producer or before the consumer receives the message. Interceptors can be used to record logs, monitor message flow, modify message content, etc. Here is an explanation of the basic concepts, definitions, rationales of Kafka interceptors and why an interceptor is an integral part of Kafka messaging:

The definition and basic principles of Kafka interceptor:

definition:Interceptor is a plug-in in Kafka for intercepting and processing in key steps in sending and receiving messages. It can capture messages and modify, record, monitor or perform other customized operations.
Basic Principles:Interceptors implement Kafka'sInterface (producer interceptor) andInterface (consumer interceptor) to implement. These two interfaces define some key methods that allow users to execute custom logic at different stages of message sending or receiving.

The reason why interceptors are an integral part of Kafka messaging:

Message customization and modification:The interceptor allows you to modify messages before or after they are sent. This is very important for implementing customized processing of messages, such as adding, deleting, or modifying specific properties of messages.
Logs and monitoring:Interceptors can be used to record logs and monitor the flow of messages. This is very helpful for analyzing system performance, debugging issues, and implementing monitoring.
Business logic integration:Interceptors allow you to integrate business logic into Kafka processes, enabling more complex message processing and operations.
Performance and statistics:Interceptors can be used to collect statistics about messaging performance, helping you better understand and optimize system behavior.

Overall, interceptors are a powerful extension mechanism provided by Kafka, allowing users to insert custom logic at different stages of messaging. This is very useful for implementing customized message processing processes, monitoring system health, and integrating business logic, and is therefore considered an integral part of Kafka messaging.

Producer Interceptor

In Kafka, a Producer Interceptor is a mechanism that allows users to execute some custom logic before or after a message is sent to Kafka. Producer interceptor implements the provided by Kafkainterface. Here are the basic steps for configuring and using a producer interceptor and the impact of the interceptor on message production:

Steps to configure and use producer interceptors:

Create an interceptor class:Create a class implementationProducerInterceptorinterface. This interface contains three main methods:configure、onSend,andonAcknowledgement。

public class CustomProducerInterceptor implements ProducerInterceptor&lt;String, String&gt; {
    @Override
    public ProducerRecord&lt;String, String&gt; onSend(ProducerRecord&lt;String, String&gt; record) {
        // Execute logic before sending the message, you can modify the message content        return record;
    }
    @Override
    public void onAcknowledgement(RecordMetadata metadata, Exception exception) {
        // Execute logic when the message is acknowledged (acknowledged)    }
    @Override
    public void close() {
        // Execute cleaning logic when the interceptor is closed    }
    @Override
    public void configure(Map&lt;String, ?&gt; configs) {
        // Get configuration information    }
}

Configure producers to use interceptors:Specify the interceptor class in the configuration that creates the producer.

Properties props = new Properties();
("", "your_bootstrap_servers");
("", "");
("", "");
("", "");
KafkaProducer<String, String> producer = new KafkaProducer<>(props);

Impact of producer interceptors on message production:

Message customization and modification:existonSendIn the method, you can get the message to be sent, modify it or add some custom attributes, and then return the modified message. This allows you to customize the message before it is sent to Kafka.
Monitoring and recording:existonAcknowledgementIn the method, you can obtain the confirmation information of the message, including partitions, offsets, etc. This can be used to monitor the acknowledgement of messages, log logs, and perform other acknowledge-related logic.
Performance statistics:Interceptors can be used to collect statistical information related to message production performance. Through monitoringonSendandonAcknowledgementMethod calls, you can collect information about message sending rate, delay, etc.
Exception handling:In the interceptor method, you can execute some exception handling logic. For example,onAcknowledgementThe method handles the possible exceptions when sending messages.

Overall, the producer interceptor provides users with the opportunity to insert custom logic during message sending for customized message processing and monitoring. When configuring and using interceptors, it is necessary to ensure that the interceptor logic is efficient to avoid excessive impact on producer performance.

Consumer Interceptor

In Kafka, a consumer interceptor is a mechanism that allows users to execute some custom logic before or after messages are pulled from Kafka to consumers. Consumer interceptor implements the Kafka-providedinterface. Here are the basic steps for configuring and using a consumer interceptor and the impact of the interceptor on message consumption:

Steps to configure and use consumer interceptors:

Create an interceptor class:Create a class implementationConsumerInterceptorinterface. This interface contains three main methods:configure、onConsume,andonCommit。

public class CustomConsumerInterceptor implements ConsumerInterceptor&lt;String, String&gt; {
    @Override
    public ConsumerRecords&lt;String, String&gt; onConsume(ConsumerRecords&lt;String, String&gt; records) {
        // Execute logic before message is consumed        return records;
    }
    @Override
    public void onCommit(Map&lt;TopicPartition, OffsetAndMetadata&gt; offsets) {
        // Execute logic when the consumer submits an offset    }
    @Override
    public void close() {
        // Execute cleaning logic when the interceptor is closed    }
    @Override
    public void configure(Map&lt;String, ?&gt; configs) {
        // Get configuration information    }
}

Configure the consumer to use the interceptor:Specify the interceptor class in the configuration that creates the consumer.

Properties props = new Properties();
("", "your_bootstrap_servers");
("", "");
("", "");
("", "your_consumer_group_id");
("", "");
KafkaConsumer<String, String> consumer = new KafkaConsumer<>(props);

Impact of consumer interceptors on message consumption:

Message customization and modification:existonConsumeIn the method, you can get the message collection that is about to be consumed, modify it, or add some custom processing logic, and then return the modified message collection. This allows you to customize the processing before the message is consumed.
Operations before expiration:existonCommitIn the method, you can obtain the partition offset information that will be submitted. This can be used to perform some logic before the consumer submits the offset, such as logging, monitoring, etc.
Monitoring and recording:Interceptors can be used to record consumers inonConsumeandonCommitThe behavior in the method helps monitor the consumption status, consumption rate, etc. of the message.
Exception handling:In the interceptor method, you can execute some exception handling logic. For example,onConsumeExceptions that may occur when processing message consumption in the method.

In general, the consumer interceptor provides users with the opportunity to insert custom logic before messages are consumed or before offsets are submitted for custom message processing, monitoring, and exception handling. When configuring and using interceptors, it is necessary to ensure that the interceptor logic is efficient to avoid excessive impact on consumer performance.

Interceptor's chain of responsibility

Interceptor responsibility chain refers to a chain composed of multiple interceptors in a certain order, each interceptor is responsible for executing some custom logic at different stages of message sending or receiving. The concept of interceptor chain of responsibility is similar to the chain of responsibility pattern in the design pattern, where each interceptor has the opportunity to process the message as it flows. In Kafka, the interceptor responsibility chain is used to insert custom logic at key points in message delivery, such as before, after message sending, before, after consumption, after consumption, etc.

The role of interceptor chain of responsibility:

Custom logic:Each interceptor can execute specific custom logic, such as modifying message content, recording logs, performing monitoring, etc.
Execute in sequence:The interceptor responsibility chain defines the order in which the interceptor is executed. Messages are processed in the order of interceptors on the chain during delivery.
Decoupling logic:Splitting different custom logic into different interceptors helps decouple business logic, making the system more flexible and maintainable.

Configure and customize the execution order of the interceptor:

In Kafka, the order of execution of the interceptor is configuredDecide. This parameter accepts a comma-separated list of interceptor classes. The interceptor will form a chain of responsibility in the order of configuration.

Example configuration parameters:

("", ".Interceptor1,.Interceptor2");

Methods to customize the execution order:

By configuring parameters:When creating a producer or consumer, configure parametersIdentify the order of interceptor classes.
accomplishconfigureMethod: In each interceptorconfigureIn the method, the class names of all interceptors are obtained through configuration information and the execution order is adjusted as needed.

@Override
public void configure(Map&lt;String, ?&gt; configs) {
    List&lt;String&gt; interceptorClasses = (List&lt;String&gt;) ("");
    // Adjust the order of execution of the interceptor as needed}

use: In the interceptor chain of responsibility, it can beconfigureUse in the methodSort the interceptor.

@Override
public void configure(Map<String, ?> configs) {
    List<String> interceptorClasses = (List<String>) ("");
    (interceptorClasses);
}

Through the above methods, you can configure and customize the execution order of the interceptor to ensure that the interceptor executes in an orderly manner according to your needs.

In general, the interceptor responsibility chain provides an effective way to customize message processing logic, and the execution order of the interceptor can be adjusted through configuration parameters to meet the needs of different scenarios.

Interceptor practical scenarios

Interceptors have a variety of scenarios in practical applications in Kafka, which provide a flexible mechanism that allows users to insert custom logic at key points in messaging. Here are some common scenarios for interceptors in practical applications and how to use interceptors to solve specific problems:

Logging:The interceptor can be used to record the sending and consumption of messages, including message content, sending time, consumption time, etc. This is very helpful for system monitoring and troubleshooting.
Message format conversion:The interceptor can be used to format the message before or after it is sent. For example, convert messages from one serialized format to another.
Message Audit:Interceptors can be used to audit during message delivery, recording the processing of messages to meet compliance requirements or audit requirements.
Performance statistics:Interceptors can be used to collect statistical information related to messaging performance, such as message processing rates, delays, etc., for performance analysis and optimization.
Exception handling:Interceptors can be used to perform some exception handling logic when messages are sent or consumed, such as recording error logs, performing retry, etc.
Message filtering:Interceptors can be used to filter before or after message is sent, and to decide whether to process messages based on business logic.
Message processing:Before or after the message is sent, an interceptor can be used to process the message, such as adding, modifying, or deleting specific properties of the message.
Monitoring system health:Interceptors can be used to monitor the health of the system and record key metrics during the messaging process to help the operation and maintenance team keep the system running properly.
Timing task triggers:Interceptors can be used to trigger timing tasks during message sending or consuming, performing some periodic operations.
Permission Control:Interceptors can be used to implement permission control for message delivery, limiting the sending or consumption of messages based on the permissions of users or roles.

By leveraging interceptors, you can insert custom logic at critical stages of messaging to meet the needs of specific scenarios. In practical applications, interceptors can be selectively used according to business needs, and the execution order of interceptors can be adjusted through configuration parameters to meet customized needs in different scenarios.

This is the end of this article about the magical operation of Kafka interceptor. For more related Kafka interceptor content, please search for my previous articles or continue browsing the related articles below. I hope everyone will support me in the future!