AWS S3 Java Embedded Mock for Integration Tests

Question

After searching the internet for a good solution to an embedded Java AWS S3 mock it seemed that S3Ninja and S3Proxy seemed to be the most popular solutions.

However there doesn't seem to be an easy way to fire these up programmatically. After giving up with S3Ninja, I tried to do it with S3Proxy but it's not quite working.

Maven Dependencies

<dependency>
    <groupId>org.gaul</groupId>
    <artifactId>s3proxy</artifactId>
    <version>${s3proxy.version}</version>
    <scope>test</scope>
</dependency>

Code

String endpoint = "http://127.0.0.1:8085";
URI uri = URI.create(endpoint);
Properties properties = new Properties();
properties.setProperty("s3proxy.authorization", "none");
properties.setProperty("s3proxy.endpoint", endpoint);
properties.setProperty("jclouds.provider", "filesystem");
properties.setProperty("jclouds.filesystem.basedir", "/tmp/s3proxy");

ContextBuilder builder = ContextBuilder
        .newBuilder("filesystem")
        .credentials("x", "x")
        .modules(ImmutableList.<Module>of(new SLF4JLoggingModule()))
        .overrides(properties);
BlobStoreContext context = builder.build(BlobStoreContext.class);
BlobStore blobStore = context.getBlobStore();

S3Proxy s3Proxy = S3Proxy.builder().awsAuthentication("x", "x").endpoint(uri).keyStore("", "").blobStore(blobStore).build();
s3Proxy.start();

BasicAWSCredentials awsCredentials = new BasicAWSCredentials("x", "x");

AmazonS3Client client = new AmazonS3Client(awsCredentials, new ClientConfiguration());
client.setEndpoint(endpoint);

// Should Throw AWS Client Exception as Bucket / Key does not exist!
GetObjectRequest objectRequest = new GetObjectRequest("bucket", "key");
S3Object object = client.getObject(objectRequest);

s3Proxy.stop();

Exception

java.lang.NoSuchMethodError: com.google.gson.internal.bind.ReflectiveTypeAdapterFactory.<init>(Lcom/google/gson/internal/ConstructorConstructor;Lcom/google/gson/FieldNamingStrategy;Lcom/google/gson/internal/Excluder;)V

at org.jclouds.json.internal.DeserializationConstructorAndReflectiveTypeAdapterFactory.<init>(DeserializationConstructorAndReflectiveTypeAdapterFactory.java:116)
at org.jclouds.json.config.GsonModule.provideGson(GsonModule.java:129)

...

at org.jclouds.providers.config.BindProviderMetadataContextAndCredentials.backend(BindProviderMetadataContextAndCredentials.java:84)

...

at org.jclouds.ContextBuilder.build(ContextBuilder.java:581)

Any help is truly appreciated. I'm sure this is a big requirement for many Java Integration Tests that interact with AWS S3.

Answer 1

Just to comment the reason is because your project is using a conflicting version of gson. S3Proxy's dep requires gson 2.5.