jetcd - A Java Client for etcd

jetcd is the official java client for etcd v3.

Note: jetcd is work-in-progress and may break backward compatibility.

Java Versions

Java 8 or above is required.

Download

Maven

<dependency>
  <groupId>io.etcd</groupId>
  <artifactId>jetcd-core</artifactId>
  <version>${jetcd-version}</version>
</dependency>

Development snapshots are available in Sonatypes's snapshot repository.

Gradle

dependencies {
    compile "io.etcd:jetcd-core:$jetcd-version"
}

Usage

// create client
Client client = Client.builder().endpoints("http://localhost:2379").build();
KV kvClient = client.getKVClient();

ByteSequence key = ByteSequence.from("test_key".getBytes());
ByteSequence value = ByteSequence.from("test_value".getBytes());

// put the key-value
kvClient.put(key, value).get();

// get the CompletableFuture
CompletableFuture<GetResponse> getFuture = kvClient.get(key);

// get the value from CompletableFuture
GetResponse response = getFuture.get();

// delete the key
kvClient.delete(key).get();

For full etcd v3 API, plesase refer to API_Reference.

Examples

The examples are standalone projects that show usage of jetcd.

Launcher

The io.etcd:jetcd-test offers a convenient utility to programmatically start & stop an isolated etcd server. This can be very useful e.g. for integration testing, like so:

import io.etcd.jetcd.Client;
import io.etcd.jetcd.launcher.EtcdCluster;
import io.etcd.jetcd.test.EtcdClusterExtension;
import org.junit.jupiter.api.extension.RegisterExtension;

@RegisterExtension static final EtcdCluster etcd = new EtcdClusterExtension("test-etcd", 1);
Client client = Client.builder().endpoints(etcd.getClientEndpoints()).build();

This launcher uses the Testcontainers framework. For more info and prerequisites visit testcontainers.org.

Versioning

The project follows Semantic Versioning.

The current major version is zero (0.y.z). Anything may change at any time. The public API should not be considered stable.

Build from source

The project can be built with Apache Maven:

mvn clean install -DskipTests

Running tests

The project is tested against a three node etcd setup started with the Launcher (above) :

$ mvn test
...

[INFO]  T E S T S
[INFO] -------------------------------------------------------
[INFO] Running TestSuite
[WARNING] Tests run: 104, Failures: 0, Errors: 0, Skipped: 3, Time elapsed: 31.308 s - in TestSuite
[INFO]
[INFO] Results:
[INFO]
[WARNING] Tests run: 104, Failures: 0, Errors: 0, Skipped: 3
...
[INFO] Reactor Summary:
[INFO]
[INFO] jetcd .............................................. SUCCESS [  0.010 s]
[INFO] jetcd-core ......................................... SUCCESS [ 55.480 s]
[INFO] jetcd-discovery-dns-srv ............................ SUCCESS [  3.225 s]
[INFO] jetcd-watch-example ................................ SUCCESS [  0.291 s]
[INFO] jetcd-simple-ctl ................................... SUCCESS [  0.028 s]
[INFO] jetcd-examples ..................................... SUCCESS [  0.000 s]
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 59.929 s
[INFO] Finished at: 2018-02-13T12:51:13-08:00
[INFO] Final Memory: 84M/443M

Troubleshooting

It recommmonds building the project before running tests so that you have artifacts locally. It will solve some problems if the latest snapshot hasn't been uploaded or network issues.

Contact

• Mailing list: etcd-dev
• IRC: #etcd on freenode.org

Contributing

See CONTRIBUTING for details on submitting patches and the contribution workflow.

Reporting bugs

See reporting bugs for details about reporting any issues.

License

jetcd is under the Apache 2.0 license. See the LICENSE file for details.