Apache Dubbo Project

Maven License

Apache Dubbo is a high-performance, Java-based open-source RPC framework. Please visit the official site for the quick start guide and documentation, as well as the wiki for news, FAQ, and release notes.

We are now collecting Dubbo user info to help us to improve Dubbo further. Kindly support us by providing your usage information on Wanted: who's using dubbo, thanks :)

Architecture

Features

Transparent interface based RPC
Intelligent load balancing
Automatic service registration and discovery
High extensibility
Runtime traffic routing
Visualized service governance

Getting started

The following code snippet comes from Dubbo Samples. You may clone the sample project and step into the dubbo-samples-api subdirectory before proceeding.

git clone https://github.com/apache/dubbo-samples.git
cd dubbo-samples/1-basic/dubbo-samples-api

There's a README file under dubbo-samples-api directory. We recommend referencing the samples in that directory by following the below-mentioned instructions:

Maven dependency

<properties>
    <dubbo.version>3.2.13-SNAPSHOT</dubbo.version>
</properties>

<dependencies>
    <dependency>
        <groupId>org.apache.dubbo</groupId>
        <artifactId>dubbo</artifactId>
        <version>${dubbo.version}</version>
    </dependency>
    <dependency>
        <groupId>org.apache.dubbo</groupId>
        <artifactId>dubbo-dependencies-zookeeper</artifactId>
        <version>${dubbo.version}</version>
        <type>pom</type>
    </dependency>
</dependencies>

Define service interfaces

package org.apache.dubbo.samples.api;

public interface GreetingsService {
    String sayHi(String name);
}

See api/GreetingsService.java on GitHub.

Implement service interface for the provider

package org.apache.dubbo.samples.provider;

import org.apache.dubbo.samples.api.GreetingsService;

public class GreetingsServiceImpl implements GreetingsService {
    @Override
    public String sayHi(String name) {
        return "hi, " + name;
    }
}

See provider/GreetingsServiceImpl.java on GitHub.

Start service provider

package org.apache.dubbo.samples.provider;


import org.apache.dubbo.config.ApplicationConfig;
import org.apache.dubbo.config.RegistryConfig;
import org.apache.dubbo.config.ServiceConfig;
import org.apache.dubbo.samples.api.GreetingsService;

import java.util.concurrent.CountDownLatch;

public class Application {
    private static String zookeeperHost = System.getProperty("zookeeper.address", "127.0.0.1");

    public static void main(String[] args) throws Exception {
        ServiceConfig<GreetingsService> service = new ServiceConfig<>();
        service.setApplication(new ApplicationConfig("first-dubbo-provider"));
        service.setRegistry(new RegistryConfig("zookeeper://" + zookeeperHost + ":2181"));
        service.setInterface(GreetingsService.class);
        service.setRef(new GreetingsServiceImpl());
        service.export();

        System.out.println("dubbo service started");
        new CountDownLatch(1).await();
    }
}

See provider/Application.java on GitHub.

Build and run the provider

mvn clean package
mvn -Djava.net.preferIPv4Stack=true -Dexec.mainClass=org.apache.dubbo.samples.provider.Application exec:java

Call remote service in the consumer

package org.apache.dubbo.samples.client;


import org.apache.dubbo.config.ApplicationConfig;
import org.apache.dubbo.config.ReferenceConfig;
import org.apache.dubbo.config.RegistryConfig;
import org.apache.dubbo.samples.api.GreetingsService;

public class Application {
    private static String zookeeperHost = System.getProperty("zookeeper.address", "127.0.0.1");

    public static void main(String[] args) {
        ReferenceConfig<GreetingsService> reference = new ReferenceConfig<>();
        reference.setApplication(new ApplicationConfig("first-dubbo-consumer"));
        reference.setRegistry(new RegistryConfig("zookeeper://" + zookeeperHost + ":2181"));
        reference.setInterface(GreetingsService.class);
        GreetingsService service = reference.get();
        String message = service.sayHi("dubbo");
        System.out.println(message);
    }
}

See client/Application.java on GitHub.

Build and run the consumer

mvn clean package
mvn -Djava.net.preferIPv4Stack=true -Dexec.mainClass=org.apache.dubbo.samples.client.Application exec:java

The consumer will print out hi, dubbo on the screen.

Next steps

Your first Dubbo application - A 101 tutorial to reveal more details, with the same code above.
Dubbo user manual - How to use Dubbo and all its features.
Dubbo developer guide - How to involve in Dubbo development.
Dubbo admin manual - How to admin and manage Dubbo services.

Building

If you want to try out the cutting-edge features, you can build with the following commands. (Java 1.8 is needed to build the master branch)

  mvn clean install

Recommended Test Environment

To avoid intermittent test failures (i.e., flaky tests), it is recommended to have a machine or virtual machine with the following specifications:

Minimum of 2CPUs.
Minimum of 2Gb of RAM.

How does the Dubbo Community collaborate?

The Dubbo Community primarily communicates on GitHub through issues, discussions, and pull requests.

Issues: We use issues to track bugs and tasks. Any work-related item is associated with an issue.
Discussions: We use discussions for questions, early proposals, and announcements. Any idea-related item is associated with a discussion.
Pull Requests: We use pull requests to merge a set of changes from contributors into Dubbo.

We have also implemented a project board to monitor all the items.

Any essential changes should be discussed on the mailing list before they happen.

Seeking for help

If you have questions such as:

What is Dubbo?
How do I use Dubbo?
Why did an unexpected result occur?

Please start a discussion at https://github.com/apache/dubbo/discussions.

However, if you encounter the following situations:

You're certain there's a bug that Dubbo needs to fix,
You believe a feature could be enhanced,
You have a detailed proposal for improving Dubbo,

Please open an issue at https://github.com/apache/dubbo/issues.

To ask effective questions, we recommend reading How To Ask Questions The Smart Way first.

Contribution

Browse the "help wanted" tasks in the Dubbo project board.
Participate in discussions on the mailing list. See the subscription guide.
Respond to queries in the discussions.
Resolve bugs reported in issues and send us a pull request.
Review existing pull requests.
Enhance the website. We typically need:
- Blog posts
- Translations for documentation
- Use cases showcasing Dubbo integration in enterprise systems.
Improve the dubbo-admin.
Contribute to the projects listed in the ecosystem.
Any other forms of contribution not listed above are also welcome.
If you're interested in contributing, please send an email to dev@dubbo.apache.org to let us know!

For further details, please refer our guide about how to contribute Dubbo.

Reporting bugs

Please follow the template for reporting any issues.

Reporting a security vulnerability

Please report security vulnerabilities to us privately.

Contact

Mailing list:
- dev list: for dev/user discussion. subscribe, unsubscribe, archive, guide
Bugs: Issues
Gitter: Gitter channel
Twitter: @ApacheDubbo

Dubbo ecosystem

Dubbo Ecosystem Entry - A GitHub group dubbo to gather all Dubbo relevant projects not appropriate in apache group yet
Dubbo Website - Apache Dubbo official website
Dubbo Samples - samples for Apache Dubbo
Dubbo Admin - The reference implementation for Dubbo admin
Dubbo Awesome - Dubbo's slides and video links in Meetup