Example on how to cache values for API calls

gistfile1.cs

#region copyright
// /* Copyright (C) think2infinity LLC  - All Rights Reserved
//  * 
//  * TimeJack
//  *
//  * Written by Stephen Reindl <stephen@think2infinity.com>, 09 2013
//  * 
// */
#endregion

#region usings

using System;
using System.Web;
using System.Web.Http;
using System.Web.Http.Controllers;
using Microsoft.AspNet.Identity;
using TimeJack.Common.Security;
using TimeJack.Model.Annotations;
using TimeJack.Model.Models;

#endregion

namespace TimeJack.Api
{
    /// <summary>
    /// Base controller for db and customer id settings
    /// </summary>
    public abstract class BaseController: ApiController
    {
        private readonly object _lock = new object();

        /// <summary>
        /// The customer this controller is referencing to.
        /// </summary>
        protected Guid CustomerId
        {
            get
            {
                if (!_customerId.HasValue)
                {
                    InitApi();
                    lock (_lock)
                    {
                        if (User.Identity.IsAuthenticated)
                        {
                            Guid? customerId = HttpContext.Current.Cache["APIID" + User.Identity.Name] as Guid?;
                            if (customerId.HasValue)
                            {
                                CustomerId = customerId.Value;
                            }
                            else
                            {
                                UserProfile user = UserManager.FindByName(User.Identity.Name);
                                if (user != null)
                                {
                                    CustomerId = user.CustomerId;
                                    HttpContext.Current.Cache["APIID" + User.Identity.Name] = user.CustomerId;
                                }
                            }
                        }
                        else
                        {
                            _customerId = Guid.Empty;
                        }
                    }
                }
                return _customerId.GetValueOrDefault();
            }
            private set { _customerId = value; }
        }

        /// <summary>
        /// 
        /// </summary>
        private ITimeJackContext _db;

        /// <summary>
        /// 
        /// </summary>
        protected ITimeJackContext Db
        {
            get
            {
                if (_db == null)
                {
                    InitApi();
                }
                return _db;
            }
            private set { _db = value; }
        }

        /// <summary>
        /// 
        /// </summary>
        protected ApplicationUserManager UserManager
        {
            get
            {
                if (_userManager == null)
                {
                    InitApi();
                }
                return _userManager;
            }
            private set { _userManager = value; }
        }

        private Guid? _customerId;
        private ApplicationUserManager _userManager;

        /// <summary>
        /// 
        /// </summary>
        /// <param name="controllerContext"></param>
        protected override void Initialize([NotNull] HttpControllerContext controllerContext)
        {
            base.Initialize(controllerContext);
        }

        /// <summary>
        /// 
        /// </summary>
        private void InitApi()
        {
            lock (_lock)
            {
                if (_db == null)
                {
                    Db = new TimeJackContext();
                    Db.Configuration.ProxyCreationEnabled = false;
                }
                if (_userManager == null)
                {
                    UserManager = new ApplicationUserManager(_db as TimeJackContext);
                }
            }
        }
    }
}