Getting an object from an Amazon S3 on Outposts bucket

Objects are the fundamental entities stored in Amazon S3 on Outposts. Every object is contained in a bucket. You must use access points to access any object in an Outpost bucket. When you specify the bucket for object operations, you use the access point Amazon Resource Name (ARN) or the access point alias. For more information about access point aliases, see Using a bucket-style alias for your S3 on Outposts bucket access point.

The following example shows the ARN format for S3 on Outposts access points, which includes the AWS Region code for the Region that the Outpost is homed to, the AWS account ID, the Outpost ID, and the access point name:

arn:aws:s3-outposts:region:account-id:outpost/outpost-id/accesspoint/accesspoint-name

For more information about S3 on Outposts ARNs, see Resource ARNs for S3 on Outposts.

With Amazon S3 on Outposts, object data is always stored on the Outpost. When AWS installs an Outpost rack, your data stays local to your Outpost to meet data-residency requirements. Your objects never leave your Outpost and are not in an AWS Region. Because the AWS Management Console is hosted in-Region, you can't use the console to upload or manage objects in your Outpost. However, you can use the REST API, AWS Command Line Interface (AWS CLI), and AWS SDKs to upload and manage your objects through your access points.

The following examples show you how to download (get) an object by using the AWS Command Line Interface (AWS CLI) and AWS SDK for Java.

Using the AWS CLI

The following example gets an object named sample-object.xml from an S3 on Outposts bucket (s3-outposts:GetObject) by using the AWS CLI. To use this command, replace each user input placeholder with your own information. For more information about this command, see get-object in the AWS CLI Reference.

aws s3api get-object --bucket arn:aws:s3-outposts:region:123456789012:outpost/op-01ac5d28a6a232904/accesspoint/example-outposts-access-point --key testkey sample-object.xml

Using the AWS SDK for Java

The following S3 on Outposts example gets an object by using the SDK for Java. To use this example, replace each user input placeholder with your own information. For more information, see GetObject in the Amazon Simple Storage Service API Reference.

import com.amazonaws.AmazonServiceException;
import com.amazonaws.SdkClientException;
import com.amazonaws.services.s3.AmazonS3;
import com.amazonaws.services.s3.AmazonS3ClientBuilder;
import com.amazonaws.services.s3.model.GetObjectRequest;
import com.amazonaws.services.s3.model.ResponseHeaderOverrides;
import com.amazonaws.services.s3.model.S3Object;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;

public class GetObject {
    public static void main(String[] args) throws IOException {
        String accessPointArn = "*** access point ARN ***";
        String key = "*** Object key ***";

        S3Object fullObject = null, objectPortion = null, headerOverrideObject = null;
        try {
            // This code expects that you have AWS credentials set up per:
            // https://docs.aws.amazon.com/sdk-for-java/v1/developer-guide/setup-credentials.html
            AmazonS3 s3Client = AmazonS3ClientBuilder.standard()
                    .enableUseArnRegion()
                    .build();

            // Get an object and print its contents.
            System.out.println("Downloading an object");
            fullObject = s3Client.getObject(new GetObjectRequest(accessPointArn, key));
            System.out.println("Content-Type: " + fullObject.getObjectMetadata().getContentType());
            System.out.println("Content: ");
            displayTextInputStream(fullObject.getObjectContent());

            // Get a range of bytes from an object and print the bytes.
            GetObjectRequest rangeObjectRequest = new GetObjectRequest(accessPointArn, key)
                    .withRange(0, 9);
            objectPortion = s3Client.getObject(rangeObjectRequest);
            System.out.println("Printing bytes retrieved.");
            displayTextInputStream(objectPortion.getObjectContent());

            // Get an entire object, overriding the specified response headers, and print the object's content.
            ResponseHeaderOverrides headerOverrides = new ResponseHeaderOverrides()
                    .withCacheControl("No-cache")
                    .withContentDisposition("attachment; filename=example.txt");
            GetObjectRequest getObjectRequestHeaderOverride = new GetObjectRequest(accessPointArn, key)
                    .withResponseHeaders(headerOverrides);
            headerOverrideObject = s3Client.getObject(getObjectRequestHeaderOverride);
            displayTextInputStream(headerOverrideObject.getObjectContent());
        } catch (AmazonServiceException e) {
            // The call was transmitted successfully, but Amazon S3 couldn't process
            // it, so it returned an error response.
            e.printStackTrace();
        } catch (SdkClientException e) {
            // Amazon S3 couldn't be contacted for a response, or the client
            // couldn't parse the response from Amazon S3.
            e.printStackTrace();
        } finally {
            // To ensure that the network connection doesn't remain open, close any open input streams.
            if (fullObject != null) {
                fullObject.close();
            }
            if (objectPortion != null) {
                objectPortion.close();
            }
            if (headerOverrideObject != null) {
                headerOverrideObject.close();
            }
        }
    }

    private static void displayTextInputStream(InputStream input) throws IOException {
        // Read the text input stream one line at a time and display each line.
        BufferedReader reader = new BufferedReader(new InputStreamReader(input));
        String line = null;
        while ((line = reader.readLine()) != null) {
            System.out.println(line);
        }
        System.out.println();
    }
}