LocalS3

LocalS3 is an Amazon S3 mock service for testing and local development. LocalS3 is based on Netty and without heavy dependencies, it starts up quickly and handles requests efficiently.

Supported Amazon S3 APIs

• AbortMultipartUpload
• CopyObject
• CreateBucket
• CreateMultipartUpload
• CompleteMultipartUpload
• DeleteBucket
• DeleteBucketEncryption
• DeleteBucketPolicy
• DeleteBucketReplication
• DeleteBucketTagging
• DeleteObject
• DeleteObjects
• DeleteObjectTagging
• GetObject
• GetObjectTagging
• GetBucketAcl
• GetBucketEncryption
• GetBucketPolicy
• GetBucketReplication
• GetBucketVersioning
• GetBucketTagging
• GetBucketLocation
• HeadBucket
• HeadObject
• ListBuckets
• ListObjects
• ListObjectsV2
• ListObjectVersions
• ListParts
• PutBucketAcl
• PutBucketEncryption
• PutBucketPolicy
• PutBucketReplication
• PutBucketVersioning
• PutBucketTagging
• PutObject
• PutObjectTagging
• UploadPart

Features

• Support S3 object versioning.
• In memory and persistence mode.

Usages

Programming with LocalS3

Developers could integrate LocalS3 into their own Java applications or testing frameworks via Java APIs.

Dependency

<dependency>
    <groupId>io.github.robothy</groupId>
    <artifactId>local-s3-rest</artifactId>
</dependency>

Run LocalS3 in In-Memory mode

By default, LocalS3 runs in In-Memory mode; all data and metadata retain in the memory.

LocalS3 localS3 = LocalS3.builder()
    .port(19090)
    .build();

localS3.start();

Call the stop method to shut down the service gracefully.

localS3.shutdown();

Run LocalS3 in Persistence mode

When LocalS3 runs in persistence mode, a data path is required. LocalS3 loads data from and stores all data into the specified path.

LocalS3 localS3 = LocalS3.builder()
    .port(19090)
    .mode(LocalS3Mode.PERSISTENCE)
    .dataDirectory("C://local-s3")
    .build();

localS3.start();

Run LocalS3 in In-Memory mode with initial data.

LocalS3 loads initial data from the specified path. Changes on such LocalS3 instance only modify the data in memory, not persist to the disk.

LocalS3 localS3 = LocalS3.builder()
    .port(-1) // assign a random port
    .dataDirectory("/data")
    .build();

localS3.start();

LocalS3 for Junit5

LocalS3 for Junit5 provides a Java annotation @LocalS3 helps you easily launch S3 services for your tests.

Dependency

<dependency>
    <groupId>io.github.robothy</groupId>
    <artifactId>local-s3-jupiter</artifactId>
    <scope>test</scope>
</dependency>

When you annotate it on test classes or test methods, the LocalS3 extension automatically inject instances with the following parameter types of test methods or lifecycle methods.

• AmazonS3
• S3Client
• LocalS3Endpoint

Example 1: Inject a AmazonS3 object to the test method parameter.

@LocalS3
class AppTest {
  @Test
  void test(AmazonS3 s3) {
    s3.createBucket("my-bucket");
  }
}

Example 2: Inject a S3Client object to the test method parameter

class AppTest {
  @Test
  @LocalS3
  void test(S3Client client) {
    client.createBucket(b -> b.bucket("my-bucket"));
  }
}

Example 3: Inject instances to junit5 lifecycle methods.

@LocalS3
class AppTest {
  
  @BeforeAll
  static void beforeAll(S3Client client) {
    client.createBucket(b -> b.bucket("my-bucket"));
  }
  
  @Test
  void test(S3Client client) {
    client.headBucket(b -> b.bucket("my-bucket"));
  }
  
  @AfterAll
  static void afterAll(S3Client client) {
    client.deleteBucket(b -> b.bucket("my-bucket"));
  }
}

Difference between @LocalS3 on test classes and test methods

If @LocalS3 is on a test class, the Junit5 extension will create a shared service for all test methods in the class and shut it down in the "after all" callback. If @LocalS3 is on a test method, the extension creates an exclusive service for the method and shut down the service in the "after each" callback.

Run LocalS3 in Docker

You can run LocalS3 in Docker since it's image is published to DockerHub.

docker run --name s3 -d -v C:\\local-s3:/data -p 8080:80 luofuxiang/local-s3

LocalS3 test container

LocalS3 provides a testcontainers implementation. You can run LocalS3 in your tests with testcontainers API.

Dependency

<dependency>
    <groupId>io.github.robothy</groupId>
    <artifactId>local-s3-testcontainers</artifactId>
</dependency>

Start LocalS3 with testcontainers

@Testcontainers
public class AppTest {

  @Container
  public LocalS3Container container = new LocalS3Container("latest")
      .withMode(LocalS3Container.Mode.IN_MEMORY)
      .withRandomHttpPort();
  
  @Test
  void test() {
    assertTrue(container.isRunning());
    int port = container.getPort();
    AmazonS3 s3 = AmazonS3ClientBuilder.standard()
        .enablePathStyleAccess()
        .withClientConfiguration(new ClientConfiguration().withSocketTimeout(1000).withConnectionTimeout(1000))
        .withEndpointConfiguration(new AwsClientBuilder.EndpointConfiguration(
            "http://localhost:" + port, "local"
        )).build();
    s3.createBucket("my-bucket");
  }
  
}

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