RPC Communication Protocol Based on HTTP1/2 - triple on Apache Dubbo

Developing triple communication services using Java interfaces

Mon, 01 Jan 0001 00:00:00 +0000

Unlike the official Google gRPC implementation, the Dubbo implementation of the triple protocol offers better usability (not bound to Protobuf), allowing you to define services directly using Java interfaces. For users looking for smooth upgrades, having no multi-language business, or unfamiliar with Protobuf, the Java interface method is the simplest way to use triple.

Below is a basic example of developing a Dubbo service using the Java interface, which uses triple protocol communication. You can view the full code for this example.

Developing Triple Communication Services Using Protobuf (IDL)

Mon, 01 Jan 0001 00:00:00 +0000

Usage

POM dependency

<plugin>
 <groupId>org.apache.dubbo</groupId>
 <artifactId>dubbo-maven-plugin</artifactId>
 <version>${dubbo.version}</version> <!-- Version 3.3.0 and above -->
 <configuration>
 <outputDir>build/generated/source/proto/main/java</outputDir> <!-- Refer to the following text for configurable parameters -->
 </configuration>
</plugin>

Configurable parameters

Parameter	Required	Default value	Description	Notes
outputDir	false	${project.build.directory}/generated-sources/protobuf/java	Generated java file storage directory
protoSourceDir	false	${basedir}/src/main/proto	proto file directory
protocArtifact	false	com.google.protobuf:protoc:3.25.0:exe:Operating System Name:Operating System Architecture	proto compiler component
protocVersion	false	3.25.0	version of protobuf-java
dubboGenerateType	false	tri	Code generation type	Can be filled with tri or tri_reactor

Service Definition

Define the Greeter service using Protocol Buffers.

Streaming Communication

Mon, 01 Jan 0001 00:00:00 +0000

In the section Choosing RPC Communication Protocol, it is mentioned that Streaming is a new RPC data transmission model provided by Dubbo3, suitable for the following scenarios:

The interface needs to send a large amount of data that cannot be placed in a single RPC request or response and needs to be sent in batches. If the application layer cannot solve sequence and performance issues using traditional multiple RPC methods, it can only be sent serially to ensure order.
In streaming scenarios, data needs to be processed in the order it is sent, and the data itself does not have fixed boundaries.
In push scenarios, multiple messages are sent and processed within the same call context.

Streaming is divided into the following three types:

Develop gRPC Services with Dubbo

Mon, 01 Jan 0001 00:00:00 +0000

This example demonstrates how to implement mutual calls between Dubbo services and standard gRPC services using the triple protocol. You can view the complete source code of the example.

As described in the Triple Protocol Specification, the triple protocol is 100% compatible with the gRPC protocol, while significantly improving usability (e.g., support for cURL, direct browser access, etc.). It can be said that triple is a more user-friendly design and implementation of gRPC.