Quick and Dirty API Proxy for TCB

ApiProxy.ashx.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Runtime.Caching;
using System.Net;
using System.Configuration;
using System.IO;

namespace TcbApiProxy
{
    /// <summary>
    /// Summary description for ApiProxy
    /// </summary>
    public class ApiProxy : IHttpHandler
    {
        private static ObjectCache requestCache;

        static ApiProxy()
        {
            requestCache = MemoryCache.Default;
        }

        public void ProcessRequest(HttpContext context)
        {
            string type = context.Request.QueryString["type"];
            string id = context.Request.QueryString["id"];

            if (!string.IsNullOrEmpty(type))
            {
                string content = "ERR";
                switch (type)
                {
                    case "root":
                        content = FetchContentFromCacheOrLive(type, ConfigurationManager.AppSettings["RootUrl"]);
                        context.Response.ContentType = "application/json";
                        context.Response.Write(content);
                        break;
                    case "ver":
                        if (!string.IsNullOrEmpty(id))
                        {
                            try
                            {
                                content = FetchContentFromCacheOrLive(string.Format("{0},id={1}", type, id), string.Format(ConfigurationManager.AppSettings["VerUrl"], id));
                                context.Response.ContentType = "application/json";
                                context.Response.Write(content);
                            }
                            catch (Exception ex)
                            {
                                if (ex.Message == "404")
                                {
                                    Throw404(context);
                                }
                                else
                                {
                                    Throw500(context);
                                }
                            }
                        }
                        else
                        {
                            Throw404(context);
                        }
                        break;
                    case "bld":
                        if (!string.IsNullOrEmpty(id))
                        {
                            try
                            {
                                content = FetchContentFromCacheOrLive(string.Format("{0},id={1}", type, id), string.Format(ConfigurationManager.AppSettings["BldUrl"], id));
                                context.Response.ContentType = "application/json";
                                context.Response.Write(content);
                            }
                            catch (Exception ex)
                            {
                                if (ex.Message == "404")
                                {
                                    Throw404(context);
                                }
                                else
                                {
                                    Throw500(context);
                                }
                            }
                        }
                        else
                        {
                            Throw404(context);
                        }
                        break;
                    default:
                        Throw404(context);
                        break;
                }
            }
            else
            {
                Throw404(context);
            }
        }

        public static string FetchContentFromCacheOrLive(string name, string url)
        {
            if (requestCache.Contains(name))
            {
                return requestCache[name] as string;
            }
            else
            {
                HttpWebRequest wreq = HttpWebRequest.CreateHttp(url);
                wreq.Headers.Add("Api-Key", ConfigurationManager.AppSettings["ApiKey"]);
                wreq.UserAgent = "Tom's friendly API Proxy - Hi Rob!";
                HttpWebResponse wres = wreq.GetResponse() as HttpWebResponse;
                if (wres.StatusCode == HttpStatusCode.OK)
                {
                    Stream str = wres.GetResponseStream();
                    TextReader tr = new StreamReader(str);
                    string content = tr.ReadToEnd();
                    tr.Close();
                    str.Close();

                    CacheItemPolicy p = new CacheItemPolicy();
                    p.AbsoluteExpiration = DateTime.Now.AddHours(1);
                    requestCache.Add(new CacheItem(name, content), p);

                    return content;
                }
                else if (wres.StatusCode == HttpStatusCode.NotFound)
                {
                    throw new Exception("404");
                }
                else
                {
                    throw new Exception("500");
                }
            }
        }

        private static void Throw404(HttpContext context)
        {
            context.Response.StatusCode = 404;
            context.Response.SuppressContent = true;
            context.Response.Flush();
            context.Response.Close();
        }

        private static void Throw500(HttpContext context)
        {
            context.Response.StatusCode = 500;
            context.Response.SuppressContent = true;
            context.Response.Flush();
            context.Response.Close();
        }

        public bool IsReusable
        {
            get
            {
                return false;
            }
        }
    }
}