Transparent Encoded Complex Ids in Request/Response DTO in ServiceStack v4. (With support for string[])

program.cs

using System;
using ServiceStack;
using System.Text;
using ServiceStack.Web;
using System.Collections.Generic;

namespace ComplexIdTest
{
	class MainClass
	{
		public static void Main()
		{
			// Very basic console host
			var appHost = new AppHost(500);
			appHost.Init();
			appHost.Start("http://*:8081/");
			Console.ReadKey();
		}
	}

	public class AppHost : AppHostHttpListenerPoolBase
	{
		public AppHost(int poolSize) : base("Complex Id Test Service", poolSize, typeof(ComplexIdTestService).Assembly) {}

		public override void Configure(Funq.Container container)
		{
			Config = new HostConfig {
				DebugMode = true,
			};
		}
	}

	[UsesEncodedAttribute]
	[Route("/Object/{Id}","GET")]
	public class GetObjectWithComplexIdRequest : IReturn<ObjectWithComplexIdResponse>
	{
		[EncodedId]
		public string Id { get; set; }
	}

	[UsesEncodedAttribute]
	public class ObjectWithComplexIdResponse
	{
		[EncodedId]
		public string[] Ids { get; set; }
	}

	public class ComplexIdTestService : Service
	{
		public ObjectWithComplexIdResponse Get(GetObjectWithComplexIdRequest request)
		{
			Console.WriteLine("The requested id is {0}", request.Id.Length);
			return new ObjectWithComplexIdResponse { Ids = new[] { "Hello/Something/Cool", "This/Is/A-Test:Id" } };
		}
	}

	public class EncodedIdAttribute : Attribute
	{
	}

	public class UsesEncodedAttribute : Attribute, IHasRequestFilter, IHasResponseFilter
	{
		IHasRequestFilter IHasRequestFilter.Copy()
		{
			return this;
		}

		IHasResponseFilter IHasResponseFilter.Copy()
		{
			return this;
		}

		public void RequestFilter(IRequest req, IResponse res, object requestDto)
		{
			// Decode the properties on the requestDto having the EncodedId attribute
			var type = requestDto.GetType();
			var properties = type.GetPublicProperties();
			foreach(var p in properties)
			{
				// Find the property marked with EncodedId that is of type string, that can be read and written to
				if(!p.HasAttribute<EncodedIdAttribute>() || !p.CanRead || !p.CanWrite)
					continue;

				// Check if the property is an Array (assume string[]) or simply string
				bool isArray = p.PropertyType.BaseType == typeof(Array);
				if(!isArray && p.PropertyType != typeof(string))
					continue;

				// Collections to store the encoded and decoded values
				List<string> encodedValues = new List<string>();
				List<string> decodedValues = new List<string>();

				// Get the value from the DTO
				var value = p.GetValue(requestDto, null);
				if(value == null)
					continue;

				// If the value is an array, then add all the values to encoded collection
				if(isArray)
					encodedValues.AddRange(value as IEnumerable<string>);
				else // Value is singular just add one value
					encodedValues.Add(value as string);

				// Decode all the values
				foreach(var encodedValue in encodedValues)
					decodedValues.Add(Encoding.UTF8.GetString(Convert.FromBase64String(encodedValue)));

				// If it is an array return an array of the decoded values
				if(isArray)
					p.SetValue(requestDto, decodedValues.ToArray(), null);
				else // Value is single string, return the first item
					p.SetValue(requestDto, decodedValues[0], null);
			}
		}

		public void ResponseFilter(IRequest req, IResponse res, object response)
		{
			// Encode properties on the response having the EncodedId attribute
			var type = response.GetType();
			var properties = type.GetPublicProperties();
			foreach(var p in properties)
			{
				// Find the property marked with EncodedId that is of type string, that can be read and written to
				if(!p.HasAttribute<EncodedIdAttribute>() || !p.CanRead || !p.CanWrite)
					continue;

				// Check if the property is an Array (assume string[]) or simply string
				bool isArray = p.PropertyType.BaseType == typeof(Array);
				if(!isArray && p.PropertyType != typeof(string))
					continue;

				// Collections to store the encoded and decoded values
				List<string> encodedValues = new List<string>();
				List<string> decodedValues = new List<string>();

				// Get the value from the response
				var value = p.GetValue(response, null);
				if(value == null)
					continue;

				// If the value is an array, then add all the values to decoded collection
				if(isArray)
					decodedValues.AddRange(value as IEnumerable<string>);
				else // Value is singular just add one value
					decodedValues.Add(value as string);

				// Encode all the values
				foreach(var decodedValue in decodedValues)
					encodedValues.Add(Convert.ToBase64String(decodedValue.ToUtf8Bytes()));

				// If it is an array return an array of the encoded values
				if(isArray)
					p.SetValue(response, encodedValues.ToArray(), null);
				else // Value is single string, return the first item
					p.SetValue(response, encodedValues[0], null);
			}
		}

		public int Priority { get { return int.MinValue; } }
	}
}