Get the policy for an Amazon S3 bucket using an Amazon SDK - Amazon Simple Storage Service
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Get the policy for an Amazon S3 bucket using an Amazon SDK

The following code examples show how to get the policy for an S3 bucket.

C++
SDK for C++
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the Amazon Code Examples Repository.

bool AwsDoc::S3::GetBucketPolicy(const Aws::String &bucketName, const Aws::Client::ClientConfiguration &clientConfig) { Aws::S3::S3Client s3_client(clientConfig); Aws::S3::Model::GetBucketPolicyRequest request; request.SetBucket(bucketName); Aws::S3::Model::GetBucketPolicyOutcome outcome = s3_client.GetBucketPolicy(request); if (!outcome.IsSuccess()) { const Aws::S3::S3Error &err = outcome.GetError(); std::cerr << "Error: GetBucketPolicy: " << err.GetExceptionName() << ": " << err.GetMessage() << std::endl; } else { Aws::StringStream policy_stream; Aws::String line; outcome.GetResult().GetPolicy() >> line; policy_stream << line; std::cout << "Retrieve the policy for bucket '" << bucketName << "':\n\n" << policy_stream.str() << std::endl; } return outcome.IsSuccess(); }
  • For API details, see GetBucketPolicy in Amazon SDK for C++ API Reference.

Java
SDK for Java 2.x
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the Amazon Code Examples Repository.

public static String getPolicy(S3Client s3, String bucketName) { String policyText; System.out.format("Getting policy for bucket: \"%s\"\n\n", bucketName); GetBucketPolicyRequest policyReq = GetBucketPolicyRequest.builder() .bucket(bucketName) .build(); try { GetBucketPolicyResponse policyRes = s3.getBucketPolicy(policyReq); policyText = policyRes.policy(); return policyText; } catch (S3Exception e) { System.err.println(e.awsErrorDetails().errorMessage()); System.exit(1); } return ""; }
  • For API details, see GetBucketPolicy in Amazon SDK for Java 2.x API Reference.

JavaScript
SDK for JavaScript V3
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the Amazon Code Examples Repository.

Create the client.

// Create service client module using ES6 syntax. import { S3Client } from "@aws-sdk/client-s3"; // Set the AWS Region. const REGION = "us-east-1"; // Create an Amazon S3 service client object. const s3Client = new S3Client({ region: REGION }); export { s3Client };

Get the bucket policy.

// Import required AWS SDK clients and commands for Node.js. import { GetBucketPolicyCommand } from "@aws-sdk/client-s3"; import { s3Client } from "./libs/s3Client.js"; // Helper function that creates an Amazon S3 service client module. // Create the parameters for calling export const bucketParams = { Bucket: "BUCKET_NAME" }; export const run = async () => { try { const data = await s3Client.send(new GetBucketPolicyCommand(bucketParams)); console.log("Success", data); return data; // For unit tests. } catch (err) { console.log("Error", err); } }; run();
Kotlin
SDK for Kotlin
Note

This is prerelease documentation for a feature in preview release. It is subject to change.

Note

There's more on GitHub. Find the complete example and learn how to set up and run in the Amazon Code Examples Repository.

suspend fun getPolicy(bucketName: String): String? { println("Getting policy for bucket $bucketName") val request = GetBucketPolicyRequest { bucket = bucketName } S3Client { region = "us-east-1" }.use { s3 -> val policyRes = s3.getBucketPolicy(request) return policyRes.policy } }
  • For API details, see GetBucketPolicy in Amazon SDK for Kotlin API reference.

Python
SDK for Python (Boto3)
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the Amazon Code Examples Repository.

class BucketWrapper: """Encapsulates S3 bucket actions.""" def __init__(self, bucket): """ :param bucket: A Boto3 Bucket resource. This is a high-level resource in Boto3 that wraps bucket actions in a class-like structure. """ self.bucket = bucket self.name = bucket.name def get_policy(self): """ Get the security policy of the bucket. :return: The security policy of the specified bucket, in JSON format. """ try: policy = self.bucket.Policy() logger.info("Got policy %s for bucket '%s'.", policy.policy, self.bucket.name) except ClientError: logger.exception("Couldn't get policy for bucket '%s'.", self.bucket.name) raise else: return json.loads(policy.policy)
  • For API details, see GetBucketPolicy in Amazon SDK for Python (Boto3) API Reference.

Ruby
SDK for Ruby
Note

There's more on GitHub. Find the complete example and learn how to set up and run in the Amazon Code Examples Repository.

# Wraps an Amazon S3 bucket policy. class BucketPolicyWrapper attr_reader :bucket_policy # @param bucket_policy [Aws::S3::BucketPolicy] A bucket policy object configured with an existing bucket. def initialize(bucket_policy) @bucket_policy = bucket_policy end # Gets the policy of a bucket. # # @return [Aws::S3::GetBucketPolicyOutput, nil] The current bucket policy. def get_policy policy = @bucket_policy.data.policy policy.respond_to?(:read) ? policy.read : policy rescue Aws::Errors::ServiceError => e puts "Couldn't get the policy for #{@bucket_policy.bucket.name}. Here's why: #{e.message}" nil end end
  • For API details, see GetBucketPolicy in Amazon SDK for Ruby API Reference.

For a complete list of Amazon SDK developer guides and code examples, see Using this service with an Amazon SDK. This topic also includes information about getting started and details about previous SDK versions.