Basic Steps to Customize SPI Extensions

Taking the RPC Protocol Plugin as an example, this section demonstrates how to use the SPI plugin provided by Dubbo to provide a custom RPC protocol implementation. If you want to understand how the SPI mechanism works and the list of built-in SPI extension points in the framework, please refer to the Reference Manual - SPI Extension.

1. Provide SPI Plugin Implementation Class

Provide a Java class that implements the org.apache.dubbo.rpc.Protocol interface.

package com.spi.demo;
import org.apache.dubbo.rpc.Protocol;

@Activate
public class CustomizedProtocol implements Protocol {
	// ...
}

2. Configure Implementation Class in the Specified File

Add a org.apache.dubbo.rpc.Protocol file in the application’s resources/META-INF/services/ directory, and include the following configuration in the file:

customized=com.spi.demo.CustomizedProtocol

3. Enable Custom Protocol Implementation Through Configuration

Modify the protocol configuration in the application to tell the Dubbo framework to use the custom protocol:

# For Spring Boot, you can modify application.yml or application.properties
dubbo
  protocol
    name: customized

or

ProtocolConfig protocol = new ProtocolConfig();
protocol.setName("cutomized");

4. More Examples

If you want to see more complete examples, please refer to other examples in this directory:

• Custom Protocol Extension
• Custom Filter Extension
• Custom Registry Extension
• Custom Router Extension