ComAmazonawsKms/runtimes/net/Extern/KMSClient.cs

using Amazon;
using Amazon.KeyManagementService;
using Wrappers_Compile;
using Amazon.Runtime;
using Amazon.Runtime.Endpoints;
using Amazon.Runtime.Internal;
using Amazon.Util;
using Com.Amazonaws.Kms;

// This extern is identified in Dafny code
// that refines the AWS SDK KMS Model
namespace software.amazon.cryptography.services.kms.internaldafny
{
    public partial class __default
    {

        public static
          _IResult<
            types.IKMSClient,
            types._IError
          >
          KMSClient()
        {
            var client = new DefaultKmsClient();

            return Result<
              types.IKMSClient,
              types._IError
            >
              .create_Success(new KeyManagementServiceShim(client));
        }

        public static
          _IResult<
            types.IKMSClient,
            types._IError
          >
          KMSClientForRegion(
            Dafny.ISequence<char> regionDafnyString
          )
        {
            string regionStr = TypeConversion.FromDafny_N6_smithy__N3_api__S6_String(regionDafnyString);
            // The ESDK uses empty string as a kind of none.
            // In the case of an AWS KMS raw key identifier there is no region element
            // an so "" is used in this case.
            if (regionStr == "") return KMSClient();
            var region = RegionEndpoint.GetBySystemName(regionStr);
            var client = new DefaultKmsClient(region);

            return Result<
              types.IKMSClient,
              types._IError
            >
              .create_Success(new KeyManagementServiceShim(client));
        }

        public static _IOption<bool> RegionMatch(
            software.amazon.cryptography.services.kms.internaldafny.types.IKMSClient client,
            Dafny.ISequence<char> region
        )
        {
            string regionStr = TypeConversion.FromDafny_N6_smithy__N3_api__S6_String(region);
            // We should never be passing anything other than KeyManagementServiceShim as the 'client'.
            // If this cast fails, that indicates that there is something wrong with
            // our code generation.
            IAmazonKeyManagementService nativeClient = ((KeyManagementServiceShim)client)._impl;
            return new Option_Some<bool>(nativeClient.Config.RegionEndpoint.SystemName.Equals(regionStr));
        }

        /// <summary>
        /// A KMS client that adds the Encryption SDK version to the user agent.
        /// </summary>
        internal class DefaultKmsClient : AmazonKeyManagementServiceClient
        {
            public DefaultKmsClient(AmazonKeyManagementServiceConfig config) : base(config)
            {
            }
            public DefaultKmsClient() : base()
            {
            }

            public DefaultKmsClient(RegionEndpoint region) : base(region)
            {
            }

            protected override void CustomizeRuntimePipeline(RuntimePipeline pipeline)
            {
                base.CustomizeRuntimePipeline(pipeline);
                pipeline.AddHandlerAfter<Marshaller>(new UserAgentHandler());
            }
        }

        /// <summary>
        /// Adds the Encryption SDK version to the user agent.
        /// </summary>
        internal class UserAgentHandler : PipelineHandler
        {
            private static readonly string UserAgentSuffix;

            static UserAgentHandler()
            {
                var runtime = Dafny.Sequence<char>.FromString("Net");
                UserAgentSuffix = new string(DafnyUserAgentSuffix(runtime).CloneAsArray());
            }

            /// <inheritdoc />
            public override void InvokeSync(IExecutionContext executionContext)
            {
                AddUserAgent(executionContext);
                base.InvokeSync(executionContext);
            }

            /// <inheritdoc />
            public override Task<T> InvokeAsync<T>(IExecutionContext executionContext)
            {
                AddUserAgent(executionContext);
                return base.InvokeAsync<T>(executionContext);
            }

            private static void AddUserAgent(IExecutionContext executionContext)
            {
                var request = executionContext.RequestContext.Request;
                request.Headers[AWSSDKUtils.UserAgentHeader] += UserAgentSuffix;
            }
        }
    }
}