java

Gradle

To install gradle, please follow gradle installation.

Tested build.gradle with Gradle version: 8.3

Install dependencies:

gradle build

Run with gradle CLI:

gradle -PmainClass=com.sigv4aSigning.SigV4ASign run

Compile fatJar (with all dependencies):

# After build completes, jar is located in ./build/libs.
gradle fatJar

Making requests using a Multi-Region Access Point (MRAP) in Amazon S3

You can access data in Amazon S3 through a Multi-Region Access Point (MRAP) using the hostname of the Multi-Region Access Point. The hostname for the request is <MRAP_alias>.accesspoint.s3-global.amazonaws.com. For more details, see Multi-Region Access Point hostnames .

Examples Overview

• If all you need is to get the headers with most common config with AWS credentials from environment variables.
• If all you need is to get the headers with most common config and explicitly passing accessKeyId and secretAccessKey.
• If you need high customization.
• Full example to get signed headers and make an API call.
• Full example to upload data/file though Amazon S3 Multi-Region Access Point (MRAP) into Amazon S3 bucket

Examples

Example 1

If all you need is to get the headers with most common config with AWS credentials from environment variables.

import com.sigv4aSigning.SigV4ASign;

import software.amazon.awssdk.auth.credentials.AwsBasicCredentials;
import software.amazon.awssdk.auth.credentials.AwsCredentials;
import software.amazon.awssdk.http.SdkHttpMethod;
import software.amazon.awssdk.regions.RegionScope;

import java.net.URI;
import java.util.List;
import java.util.Map;

public class MyClass {
    public static void main(String[] args) {
        SigV4ASign sigV4ASign = SigV4ASign.create();

        String url = "https://<MRAP_alias>.accesspoint.s3-global.amazonaws.com/<s3-object-key>";
        URI uri = URI.create(url);
        String serviceName = "s3";
        RegionScope globalRegion = RegionScope.GLOBAL;
        SdkHttpMethod method = SdkHttpMethod.GET;

        Map<String, List<String>> headers = sigV4ASign.getHeadersBasic(serviceName, globalRegion, method, uri);
        System.out.println(headers);
    }
}

Example 2

If all you need is to get the headers with most common config and explicitly passing accessKeyId and secretAccessKey.

import com.sigv4aSigning.SigV4ASign;

import software.amazon.awssdk.auth.credentials.AwsBasicCredentials;
import software.amazon.awssdk.auth.credentials.AwsCredentials;
import software.amazon.awssdk.http.SdkHttpMethod;
import software.amazon.awssdk.regions.RegionScope;

import java.net.URI;
import java.util.List;
import java.util.Map;

public class MyClass {
    public static void main(String[] args) {
        String accessKeyId = "<ACCESS-KEY-ID-HERE>";
        String secretAccessKey = "<SECRET-ACCESS-KEY-HERE>";

        AwsCredentials awsCredentials = AwsBasicCredentials.create(accessKeyId, secretAccessKey);
        SigV4ASign sigV4ASign = SigV4ASign.create(awsCredentials);

        String url = "https://<MRAP_alias>.accesspoint.s3-global.amazonaws.com/<s3-object-key>";
        URI uri = URI.create(url);
        String serviceName = "s3";
        RegionScope globalRegion = RegionScope.GLOBAL;
        SdkHttpMethod method = SdkHttpMethod.GET;

        Map<String, List<String>> headers = sigV4ASign.getHeadersBasic(serviceName, globalRegion, method, uri);
        System.out.println(headers);
    }
}

Example 3

If you need high customization.

import com.sigv4aSigning.SigV4ASign;

import software.amazon.awssdk.auth.signer.AwsSignerExecutionAttribute;
import software.amazon.awssdk.core.interceptor.ExecutionAttributes;
import software.amazon.awssdk.http.SdkHttpFullRequest;
import software.amazon.awssdk.http.SdkHttpMethod;
import software.amazon.awssdk.regions.RegionScope;

import java.net.URI;
import java.util.List;
import java.util.Map;

public class MyClass {
    public static void main(String[] args) {
        SigV4ASign sigV4ASign = SigV4ASign.create();

        String url = "https://<MRAP_alias>.accesspoint.s3-global.amazonaws.com/<s3-object-key>";
        URI uri = URI.create(url);
        String serviceName = "s3";
        RegionScope globalRegion = RegionScope.GLOBAL;
        SdkHttpMethod method = SdkHttpMethod.GET;

        SdkHttpFullRequest request = SdkHttpFullRequest.builder()
                .method(method)
                .encodedPath(uri.toString())
                .port(SigV4ASign.PORT)
                .protocol(SigV4ASign.PROTOCOL_HTTPS)
                .host(uri.getHost())
                .build();

        ExecutionAttributes ea = new ExecutionAttributes();
        ea.putAttribute(AwsSignerExecutionAttribute.AWS_CREDENTIALS, sigV4ASign.getAwsCredentials());
        ea.putAttribute(AwsSignerExecutionAttribute.SERVICE_SIGNING_NAME, serviceName);

        Map<String, List<String>> headers = sigV4ASign.getHeaders(request, ea, globalRegion);
        System.out.println(headers);
    }
}

Example 4

Full example to get signed headers and make an API call.

import com.sigv4aSigning.SigV4ASign;

import software.amazon.awssdk.auth.signer.AwsSignerExecutionAttribute;
import software.amazon.awssdk.core.interceptor.ExecutionAttributes;
import software.amazon.awssdk.http.SdkHttpFullRequest;
import software.amazon.awssdk.http.SdkHttpMethod;
import software.amazon.awssdk.regions.RegionScope;


import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URI;
import java.net.URL;
import java.util.List;
import java.util.Map;

public class MyClass {
    public static void main(String[] args) {
        SigV4ASign sigV4ASign = SigV4ASign.create();

        String url = "https://<MRAP_alias>.accesspoint.s3-global.amazonaws.com/<s3-object-key>";
        URI uri = URI.create(url);
        String serviceName = "s3";
        RegionScope globalRegion = RegionScope.GLOBAL;
        SdkHttpMethod method = SdkHttpMethod.GET;

        SdkHttpFullRequest request = SdkHttpFullRequest.builder()
                .method(method)
                .encodedPath(uri.toString())
                .port(SigV4ASign.PORT)
                .protocol(SigV4ASign.PROTOCOL_HTTPS)
                .host(uri.getHost())
                .build();

        ExecutionAttributes ea = new ExecutionAttributes();
        ea.putAttribute(AwsSignerExecutionAttribute.AWS_CREDENTIALS, sigV4ASign.getAwsCredentials());
        ea.putAttribute(AwsSignerExecutionAttribute.SERVICE_SIGNING_NAME, serviceName);

        Map<String, List<String>> headers = sigV4ASign.getHeaders(request, ea, globalRegion);

        try {
            URL urlObj = new URL(url);
            HttpURLConnection con = (HttpURLConnection) urlObj.openConnection();
            con.setRequestMethod("GET");
            headers.forEach((key, value) -> con.setRequestProperty(key, value.get(0)));

            BufferedReader in = new BufferedReader(new InputStreamReader(con.getInputStream()));
            String line;
            StringBuffer sb = new StringBuffer();

            while ((line = in.readLine()) != null) {
                sb.append(line);
            }

            in.close();
            con.disconnect();
            System.out.println(sb);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

Example 5

Full example to upload data/file through MRAP into an S3 bucket.

import com.sigv4aSigning.SigV4ASign;

import software.amazon.awssdk.auth.signer.AwsSignerExecutionAttribute;
import software.amazon.awssdk.core.interceptor.ExecutionAttributes;
import software.amazon.awssdk.core.sync.RequestBody;
import software.amazon.awssdk.http.SdkHttpFullRequest;
import software.amazon.awssdk.http.SdkHttpMethod;
import software.amazon.awssdk.regions.RegionScope;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.net.HttpURLConnection;
import java.net.URI;
import java.net.URL;
import java.util.List;
import java.util.Map;

public class MyClass {
    public static void main(String[] args) {
        SigV4ASign sigV4ASign = SigV4ASign.create();

        String url = "https://<MRAP_alias>.accesspoint.s3-global.amazonaws.com/<s3-object-key>";
        URI uri = URI.create(url);
        String serviceName = "s3";
        RegionScope globalRegion = RegionScope.GLOBAL;
        SdkHttpMethod method = SdkHttpMethod.PUT;
        String requestBody = "hello world";

        SdkHttpFullRequest request = SdkHttpFullRequest.builder()
                .method(method)
                .encodedPath(uri.toString())
                .port(SigV4ASign.PORT)
                .protocol(SigV4ASign.PROTOCOL_HTTPS)
                .host(uri.getHost())
                .contentStreamProvider(RequestBody.fromString(requestBody).contentStreamProvider())
                .build();

        ExecutionAttributes ea = new ExecutionAttributes();
        ea.putAttribute(AwsSignerExecutionAttribute.AWS_CREDENTIALS, sigV4ASign.getAwsCredentials());
        ea.putAttribute(AwsSignerExecutionAttribute.SERVICE_SIGNING_NAME, serviceName);

        Map<String, List<String>> headers = sigV4ASign.getHeaders(request, ea, globalRegion);

        try {
            URL urlObj = new URL(url);
            HttpURLConnection con = (HttpURLConnection) urlObj.openConnection();
            con.setDoOutput(true);
            con.setRequestMethod("PUT");
            headers.forEach((key, value) -> con.setRequestProperty(key, value.get(0)));

            // Handle PUT body payload
            OutputStreamWriter out = new OutputStreamWriter(
                    con.getOutputStream());
            out.write(requestBody);
            out.close();

            BufferedReader in = new BufferedReader(new InputStreamReader(con.getInputStream()));
            String line;
            StringBuffer sb = new StringBuffer();

            while ((line = in.readLine()) != null) {
                sb.append(line);
            }

            in.close();
            con.disconnect();
            System.out.println(sb);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}