Dart

S3 Get Bucket Policy

See more Amazon S3 (new) Examples

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.

Dart

import 'package:chilkat/chilkat.dart';

void main() {
  // 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.

  final rest = CkRest();

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

  // Provide AWS credentials.
  final authAws = CkAuthAws();
  authAws.accessKey = 'AWS_ACCESS_KEY';
  authAws.secretKey = 'AWS_SECRET_KEY';
  authAws.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.region = 'us-west-2';

  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.host = 'chilkat.ocean.s3.amazonaws.com';

  // Get the policy.
  final String responseJsonStr;
  try {
    responseJsonStr = rest.fullRequestNoBody('GET', '/?policy');
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

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

  print('response body: $responseJsonStr');

  // Load the JSON and display in a more human-readable manner:
  final json = CkJsonObject();
  json.load(responseJsonStr);
  json.emitCompact = false;
  print(json.emit());

  // Sample output:

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