Use PutBucketLogging with an AWS SDK or command line tool

The following code example shows how to use PutBucketLogging.

.NET

AWS SDK for .NET

Note

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

    using System;
    using System.IO;
    using System.Threading.Tasks;
    using Amazon.S3;
    using Amazon.S3.Model;
    using Microsoft.Extensions.Configuration;

    /// <summary>
    /// This example shows how to enable logging on an Amazon Simple Storage
    /// Service (Amazon S3) bucket. You need to have two Amazon S3 buckets for
    /// this example. The first is the bucket for which you wish to enable
    /// logging, and the second is the location where you want to store the
    /// logs.
    /// </summary>
    public class ServerAccessLogging
    {
        private static IConfiguration _configuration = null!;

        public static async Task Main()
        {
            LoadConfig();

            string bucketName = _configuration["BucketName"];
            string logBucketName = _configuration["LogBucketName"];
            string logObjectKeyPrefix = _configuration["LogObjectKeyPrefix"];
            string accountId = _configuration["AccountId"];

            // If the AWS Region defined for your default user is different
            // from the Region where your Amazon S3 bucket is located,
            // pass the Region name to the Amazon S3 client object's constructor.
            // For example: RegionEndpoint.USWest2 or RegionEndpoint.USEast2.
            IAmazonS3 client = new AmazonS3Client();

            try
            {
                // Update bucket policy for target bucket to allow delivery of logs to it.
                await SetBucketPolicyToAllowLogDelivery(
                    client,
                    bucketName,
                    logBucketName,
                    logObjectKeyPrefix,
                    accountId);

                // Enable logging on the source bucket.
                await EnableLoggingAsync(
                    client,
                    bucketName,
                    logBucketName,
                    logObjectKeyPrefix);
            }
            catch (AmazonS3Exception e)
            {
                Console.WriteLine($"Error: {e.Message}");
            }
        }

        /// <summary>
        /// This method grants appropriate permissions for logging to the
        /// Amazon S3 bucket where the logs will be stored.
        /// </summary>
        /// <param name="client">The initialized Amazon S3 client which will be used
        /// to apply the bucket policy.</param>
        /// <param name="sourceBucketName">The name of the source bucket.</param>
        /// <param name="logBucketName">The name of the bucket where logging
        /// information will be stored.</param>
        /// <param name="logPrefix">The logging prefix where the logs should be delivered.</param>
        /// <param name="accountId">The account id of the account where the source bucket exists.</param>
        /// <returns>Async task.</returns>
        public static async Task SetBucketPolicyToAllowLogDelivery(
            IAmazonS3 client,
            string sourceBucketName,
            string logBucketName,
            string logPrefix,
            string accountId)
        {
            var resourceArn = @"""arn:aws:s3:::" + logBucketName + "/" + logPrefix + @"*""";

            var newPolicy = @"{
                                ""Statement"":[{
                                ""Sid"": ""S3ServerAccessLogsPolicy"",
                                ""Effect"": ""Allow"",
                                ""Principal"": { ""Service"": ""logging.s3.amazonaws.com"" },
                                ""Action"": [""s3:PutObject""],
                                ""Resource"": [" + resourceArn + @"],
                                ""Condition"": {
                                ""ArnLike"": { ""aws:SourceArn"": ""arn:aws:s3:::" + sourceBucketName + @""" },
                                ""StringEquals"": { ""aws:SourceAccount"": """ + accountId + @""" }
                                        }
                                    }]
                                }";
            Console.WriteLine($"The policy to apply to bucket {logBucketName} to enable logging:");
            Console.WriteLine(newPolicy);

            PutBucketPolicyRequest putRequest = new PutBucketPolicyRequest
            {
                BucketName = logBucketName,
                Policy = newPolicy,
            };
            await client.PutBucketPolicyAsync(putRequest);
            Console.WriteLine("Policy applied.");
        }

        /// <summary>
        /// This method enables logging for an Amazon S3 bucket. Logs will be stored
        /// in the bucket you selected for logging. Selected prefix
        /// will be prepended to each log object.
        /// </summary>
        /// <param name="client">The initialized Amazon S3 client which will be used
        /// to configure and apply logging to the selected Amazon S3 bucket.</param>
        /// <param name="bucketName">The name of the Amazon S3 bucket for which you
        /// wish to enable logging.</param>
        /// <param name="logBucketName">The name of the Amazon S3 bucket where logging
        /// information will be stored.</param>
        /// <param name="logObjectKeyPrefix">The prefix to prepend to each
        /// object key.</param>
        /// <returns>Async task.</returns>
        public static async Task EnableLoggingAsync(
            IAmazonS3 client,
            string bucketName,
            string logBucketName,
            string logObjectKeyPrefix)
        {
            Console.WriteLine($"Enabling logging for bucket {bucketName}.");
            var loggingConfig = new S3BucketLoggingConfig
            {
                TargetBucketName = logBucketName,
                TargetPrefix = logObjectKeyPrefix,
            };

            var putBucketLoggingRequest = new PutBucketLoggingRequest
            {
                BucketName = bucketName,
                LoggingConfig = loggingConfig,
            };
            await client.PutBucketLoggingAsync(putBucketLoggingRequest);
            Console.WriteLine($"Logging enabled.");
        }

        /// <summary>
        /// Loads configuration from settings files.
        /// </summary>
        public static void LoadConfig()
        {
            _configuration = new ConfigurationBuilder()
                .SetBasePath(Directory.GetCurrentDirectory())
                .AddJsonFile("settings.json") // Load settings from .json file.
                .AddJsonFile("settings.local.json", true) // Optionally, load local settings.
                .Build();
        }
    }

• For API details, see PutBucketLogging in AWS SDK for .NET API Reference.