(Java) S3 Get Bucket Policy

Demonstrates how to send a GET request to fetch the policy of a specified bucket. The following information is quoted from the AWS REST API reference documentation at http://docs.aws.amazon.com/AmazonS3/latest/API/RESTBucketGETpolicy.html

To use this operation, you must have GetPolicy permissions on the specified bucket, and you must be the bucket owner.

If you don't have GetPolicy permissions, Amazon S3 returns a 403 Access Denied error. If you have the correct permissions, but you're not the bucket owner, Amazon S3 returns a 405 Method Not Allowed error. If the bucket does not have a policy, Amazon S3 returns a 404 Policy Not found error. There are restrictions about who can create bucket policies and which objects in a bucket they can apply to. For more information, go to Using Bucket Policies.

Important: This example requires Chilkat v9.5.0.66 or greater.

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import com.chilkatsoft.*;

public class ChilkatExample {

  static {
    try {
        System.loadLibrary("chilkat");
    } catch (UnsatisfiedLinkError e) {
      System.err.println("Native code library failed to load.\n" + e);
      System.exit(1);
    }
  }

  public static void main(String argv[])
  {
    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    // Important: This example requires Chilkat v9.5.0.66 or greater.

    CkRest rest = new CkRest();

    // Connect to the Amazon AWS REST server in the desired region.
    boolean bTls = true;
    int port = 443;
    boolean bAutoReconnect = true;
    boolean success = rest.Connect("s3-us-west-2.amazonaws.com",port,bTls,bAutoReconnect);

    // Provide AWS credentials.
    CkAuthAws authAws = new CkAuthAws();
    authAws.put_AccessKey("AWS_ACCESS_KEY");
    authAws.put_SecretKey("AWS_SECRET_KEY");
    authAws.put_ServiceName("s3");

    // This particular bucket is in the Oregon region, as opposed to the US Standard,
    // therefore the Region must be set appropriately.
    // Also note that we connected to "s3-us-west-2.amazonaws.com".
    authAws.put_Region("us-west-2");

    success = rest.SetAuthAws(authAws);

    // Note: The above REST connection and setup of the AWS credentials
    // can be done once.  After connecting, any number of REST calls can be made.
    // The "auto reconnect" property passed to rest.Connect indicates that if
    // the connection is lost, a REST method call will automatically reconnect
    // if needed.
    // --------------------------------------------------------------------------

    // Set the bucket name via the HOST header.
    // In this case, the bucket name is "chilkat.ocean".
    // Note that the Host header should use "bucketName.s3.amazonaws.com", not "bucketName.s3-us-west-2.amazonaws.com"
    rest.put_Host("chilkat.ocean.s3.amazonaws.com");

    // Get the policy.
    String responseJsonStr = rest.fullRequestNoBody("GET","/?policy");
    if (rest.get_LastMethodSuccess() != true) {
        System.out.println(rest.lastErrorText());
        return;
        }

    // When successful, the S3 Storage service will respond with a 200 response code,
    // with an XML body.  
    if (rest.get_ResponseStatusCode() != 200) {
        // Examine the request/response to see what happened.
        System.out.println("response status code = " + rest.get_ResponseStatusCode());
        System.out.println("response status text = " + rest.responseStatusText());
        System.out.println("response header: " + rest.responseHeader());
        System.out.println("response body: " + responseJsonStr);
        System.out.println("---");
        System.out.println("LastRequestStartLine: " + rest.lastRequestStartLine());
        System.out.println("LastRequestHeader: " + rest.lastRequestHeader());
        }

    System.out.println("response body: " + responseJsonStr);

    // Load the JSON and display in a more human-readable manner:
    CkJsonObject json = new CkJsonObject();
    json.Load(responseJsonStr);
    json.put_EmitCompact(false);
    System.out.println(json.emit());

    // Sample output:

    // 	{ 
    // 	  "Version": "2012-10-17",
    // 	  "Statement": [
    // 	    { 
    // 	      "Effect": "Allow",
    // 	      "Resource": "arn:aws:s3.asp">chilkat.ocean/",
    // 	      "Principal": "*"
    // 	    }
    // 	  ]
    // 	}
    // 
  }
}