I am currently working on a sideproject and have the basic foundation and architecture I want in place for the site. I wanted to get your opinion and thoughts on my current practices and methods before I get too deep down the rabbit hole and any potential issues would be difficult to remove.

• A Custom 'SubdomainRoute' inheriting 'Route' is created that takes an additional parameter 'sub'. It then overrides GetRouteData and compares the current subdomain (either the subdomain, or a '?sub=blah' query param) against the routes specified subdomain.

    using System.IO;
    using System.Linq;
    using System.Web;
    using System.Web.Mvc;
    using System.Web.Routing;
  
    namespace Teknik
    {
        public class SubdomainRoute : Route
        {
            public string Subdomain { get; set; }
  
            public SubdomainRoute(string subdomain, string url, IRouteHandler handler)
            : base(url, handler)
            {
                this.Subdomain = subdomain;
            }
            public SubdomainRoute(string subdomain, string url, RouteValueDictionary defaults, IRouteHandler handler)
            : base(url, defaults, handler)
            {
                this.Subdomain = subdomain;
            }
  
            public SubdomainRoute(string subdomain, string url, RouteValueDictionary defaults, RouteValueDictionary constraints, IRouteHandler handler)
            : base(url, defaults, constraints, handler)
            {
                this.Subdomain = subdomain;
            }
  
            public SubdomainRoute(string subdomain, string url, RouteValueDictionary defaults, RouteValueDictionary constraints, RouteValueDictionary dataTokens, IRouteHandler handler)
            : base(url, defaults, constraints, dataTokens, handler)
            {
                this.Subdomain = subdomain;
            }
  
            public override RouteData GetRouteData(HttpContextBase httpContext)
            {
                var routeData = base.GetRouteData(httpContext);
                if (routeData == null) return null; // Only look at the subdomain if this route matches in the first place.
                string subdomain = httpContext.Request.QueryString["sub"]; // A subdomain specified as a query parameter takes precedence over the hostname.
                if (subdomain == null)
                {
                    string host = httpContext.Request.Headers["Host"];
                    subdomain = host.GetSubdomain();
                }
                else
                {
                    if (routeData.Values["sub"] == null)
                    {
                        routeData.Values["sub"] = subdomain;
                    }
                    else
                    {
                        subdomain = routeData.Values["sub"].ToString();
                    }
                }
  
                //routeData.Values["sub"] = subdomain;
                if (Subdomain == "*" || Subdomain == subdomain)
                {
                    return routeData;
                }
                return null;
            }
  
            public override VirtualPathData GetVirtualPath(RequestContext requestContext, RouteValueDictionary values)
            {
                object subdomainParam = requestContext.HttpContext.Request.QueryString["sub"];
                if (subdomainParam != null && values["sub"] == null)
                    values["sub"] = subdomainParam;
                return base.GetVirtualPath(requestContext, values); // we now have the route based on subdomain
            }
        }
    }
  

• The routes are added practically the same as the normal route, with the addition of the sub param. I have one subdomain set aside for the dev site ('dev'), which is basically a copy of the routing of the normal subdomain with the Area tacked on as the first url section.

    public override void RegisterArea(AreaRegistrationContext context)
    {
        context.MapSubdomainRoute(
             "About.Index", // Route name
             "dev", // Subdomain
             "About",    // URL with parameters 
             new { controller = "About", action = "Index" },  // Parameter defaults 
             new[] { typeof(Controllers.AboutController).Namespace }
         );
        context.MapSubdomainRoute(
             "About.Index", // Route name
             "about", // Subdomain
             "",    // URL with parameters 
             new { controller = "About", action = "Index" },  // Parameter defaults 
             new[] { typeof(Controllers.AboutController).Namespace }
         );
    }
  

• To generate a link using the subdomain routing, I created a UrlHelper extension that will take the subdomain you want, the route name, and the route values you want to use. By specifying the route name, and defining a common naming convention for the names, I don't have to deal with parsing the route table to find a valid route, since I know exactly which route I want to use. This extension will then attach the correct subdomain or query param depending on the subdomain provided and the current subdomain of the current page.

    using System;
    using System.Collections.Generic;
    using System.Collections.Specialized;
    using System.Linq;
    using System.Text.RegularExpressions;
    using System.Web;
    using System.Web.Mvc;
    using System.Web.Routing;
    using System.Web.UI;
  
    namespace Teknik
    {
        public static class UrlExtensions
        {
            public static string SubRouteUrl(this UrlHelper url, string sub, string routeName)
            {
                return url.SubRouteUrl(sub, routeName, null);
            }
  
            /// <summary>
            /// Generates a full URL given the specified sub domain and route name
            /// </summary>
            /// <param name="url"></param>
            /// <param name="sub"></param>
            /// <param name="routeName"></param>
            /// <param name="routeValues"></param>
            /// <returns></returns>
            public static string SubRouteUrl(this UrlHelper url, string sub, string routeName, object routeValues)
            {
                string host = url.RequestContext.HttpContext.Request.Url.Authority;
  
                string domain = host;
                string rightUrl = string.Empty;
  
                // get current subdomain
                string curSub = host.GetSubdomain();
                var split = host.Split('.'); // split the host by '.'
                if (split.Count() > 2)
                {
                    int index = host.IndexOf('.') + 1;
                    if (index >= 0 && index < host.Length)
                        domain = host.Substring(index, (host.Length - index));
                }
  
                // Grab the sub from parameters if it exists
                string subParam = url.RequestContext.HttpContext.Request.QueryString["sub"]; // A subdomain specified as a query parameter takes precedence over the hostname.
  
                // If the param is not being used, we will use the curSub
                if (string.IsNullOrEmpty(subParam))
                {
                    string firstSub = (curSub == "dev") ? "dev" : sub;
                    if (!string.IsNullOrEmpty(firstSub))
                    {
                        routeName = firstSub + "." + routeName;
                        domain = firstSub + "." + domain;
                    }
                }
                else
                {
                    string desiredSub = (subParam == "dev") ? "dev" : sub;
                    routeName = desiredSub + "." + routeName;
                    domain = host;
                }
  
                try
                {
                    rightUrl = url.RouteUrl(routeName, routeValues);
                }
                catch (ArgumentException)
                {
  
                }
  
                string absoluteAction = string.Format("{0}://{1}{2}", url.RequestContext.HttpContext.Request.Url.Scheme, domain, rightUrl);
  
                if (!string.IsNullOrEmpty(subParam) && subParam != "dev")
                {
                    absoluteAction = absoluteAction.SetUrlParameter("sub", sub);
                }
  
                return absoluteAction;
            }
            public static string GetUrlParameters(this string url)
            {
                Uri uri = new Uri(url);
                var queryParts = HttpUtility.ParseQueryString(uri.Query);
                return queryParts.ToString();
            }
  
            public static string SetUrlParameter(this string url, string paramName, string value)
            {
                return new Uri(url).SetParameter(paramName, value).ToString();
            }
  
            public static Uri SetParameter(this Uri url, string paramName, string value)
            {
                var queryParts = HttpUtility.ParseQueryString(url.Query);
                queryParts[paramName] = value;
                return new Uri(url.AbsoluteUriExcludingQuery() + '?' + queryParts.ToString());
            }
  
            public static string AbsoluteUriExcludingQuery(this Uri url)
            {
                return url.AbsoluteUri.Split('?').FirstOrDefault() ?? String.Empty;
            }
            public static string GetSubdomain(this string host)
            {
                if (host.IndexOf(":") >= 0)
                    host = host.Substring(0, host.IndexOf(":"));
  
                Regex tldRegex = new Regex(@"\.[a-z]{2,3}\.[a-z]{2}$");
                host = tldRegex.Replace(host, "");
                tldRegex = new Regex(@"\.[a-z]{2,4}$");
                host = tldRegex.Replace(host, "");
  
                if (host.Split('.').Length > 1)
                    return host.Substring(0, host.IndexOf("."));
                else
                    return string.Empty;
            }
        }
    }
  

The source can be found here: http://git.teknik.io/Teknikode/TeknikASP

You can view a live demo here: https://dev.teknik.io/

Thanks in advance for any thoughts or concerns.

I am currently working on a side-project and have the basic foundation and architecture I want in place for the site. I wanted to get your opinion and thoughts on my current practices and methods before I get too deep down the rabbit hole and any potential issues would be difficult to remove.

• A custom SubdomainRoute inheriting 'Route' is created that takes an additional parameter 'sub'. It then overrides GetRouteData and compares the current subdomain (either the subdomain, or a '?sub=blah' query param) against the routes specified subdomain.

    using System.IO;
    using System.Linq;
    using System.Web;
    using System.Web.Mvc;
    using System.Web.Routing;
  
    namespace Teknik
    {
        public class SubdomainRoute : Route
        {
            public string Subdomain { get; set; }
  
            public SubdomainRoute(string subdomain, string url, IRouteHandler handler)
            : base(url, handler)
            {
                this.Subdomain = subdomain;
            }
            public SubdomainRoute(string subdomain, string url, RouteValueDictionary defaults, IRouteHandler handler)
            : base(url, defaults, handler)
            {
                this.Subdomain = subdomain;
            }
  
            public SubdomainRoute(string subdomain, string url, RouteValueDictionary defaults, RouteValueDictionary constraints, IRouteHandler handler)
            : base(url, defaults, constraints, handler)
            {
                this.Subdomain = subdomain;
            }
  
            public SubdomainRoute(string subdomain, string url, RouteValueDictionary defaults, RouteValueDictionary constraints, RouteValueDictionary dataTokens, IRouteHandler handler)
            : base(url, defaults, constraints, dataTokens, handler)
            {
                this.Subdomain = subdomain;
            }
  
            public override RouteData GetRouteData(HttpContextBase httpContext)
            {
                var routeData = base.GetRouteData(httpContext);
                if (routeData == null) return null; // Only look at the subdomain if this route matches in the first place.
                string subdomain = httpContext.Request.QueryString["sub"]; // A subdomain specified as a query parameter takes precedence over the hostname.
                if (subdomain == null)
                {
                    string host = httpContext.Request.Headers["Host"];
                    subdomain = host.GetSubdomain();
                }
                else
                {
                    if (routeData.Values["sub"] == null)
                    {
                        routeData.Values["sub"] = subdomain;
                    }
                    else
                    {
                        subdomain = routeData.Values["sub"].ToString();
                    }
                }
  
                //routeData.Values["sub"] = subdomain;
                if (Subdomain == "*" || Subdomain == subdomain)
                {
                    return routeData;
                }
                return null;
            }
  
            public override VirtualPathData GetVirtualPath(RequestContext requestContext, RouteValueDictionary values)
            {
                object subdomainParam = requestContext.HttpContext.Request.QueryString["sub"];
                if (subdomainParam != null && values["sub"] == null)
                    values["sub"] = subdomainParam;
                return base.GetVirtualPath(requestContext, values); // we now have the route based on subdomain
            }
        }
    }
  

• The routes are added practically the same as the normal route, with the addition of the sub param. I have one subdomain set aside for the dev site ('dev'), which is basically a copy of the routing of the normal subdomain with the Area tacked on as the first url section.

    public override void RegisterArea(AreaRegistrationContext context)
    {
        context.MapSubdomainRoute(
             "About.Index", // Route name
             "dev", // Subdomain
             "About",    // URL with parameters 
             new { controller = "About", action = "Index" },  // Parameter defaults 
             new[] { typeof(Controllers.AboutController).Namespace }
         );
        context.MapSubdomainRoute(
             "About.Index", // Route name
             "about", // Subdomain
             "",    // URL with parameters 
             new { controller = "About", action = "Index" },  // Parameter defaults 
             new[] { typeof(Controllers.AboutController).Namespace }
         );
    }
  

• To generate a link using the subdomain routing, I created a UrlHelper extension that will take the subdomain you want, the route name, and the route values you want to use. By specifying the route name, and defining a common naming convention for the names, I don't have to deal with parsing the route table to find a valid route, since I know exactly which route I want to use. This extension will then attach the correct subdomain or query param depending on the subdomain provided and the current subdomain of the current page.

    using System;
    using System.Collections.Generic;
    using System.Collections.Specialized;
    using System.Linq;
    using System.Text.RegularExpressions;
    using System.Web;
    using System.Web.Mvc;
    using System.Web.Routing;
    using System.Web.UI;
  
    namespace Teknik
    {
        public static class UrlExtensions
        {
            public static string SubRouteUrl(this UrlHelper url, string sub, string routeName)
            {
                return url.SubRouteUrl(sub, routeName, null);
            }
  
            /// <summary>
            /// Generates a full URL given the specified sub domain and route name
            /// </summary>
            /// <param name="url"></param>
            /// <param name="sub"></param>
            /// <param name="routeName"></param>
            /// <param name="routeValues"></param>
            /// <returns></returns>
            public static string SubRouteUrl(this UrlHelper url, string sub, string routeName, object routeValues)
            {
                string host = url.RequestContext.HttpContext.Request.Url.Authority;
  
                string domain = host;
                string rightUrl = string.Empty;
  
                // get current subdomain
                string curSub = host.GetSubdomain();
                var split = host.Split('.'); // split the host by '.'
                if (split.Count() > 2)
                {
                    int index = host.IndexOf('.') + 1;
                    if (index >= 0 && index < host.Length)
                        domain = host.Substring(index, (host.Length - index));
                }
  
                // Grab the sub from parameters if it exists
                string subParam = url.RequestContext.HttpContext.Request.QueryString["sub"]; // A subdomain specified as a query parameter takes precedence over the hostname.
  
                // If the param is not being used, we will use the curSub
                if (string.IsNullOrEmpty(subParam))
                {
                    string firstSub = (curSub == "dev") ? "dev" : sub;
                    if (!string.IsNullOrEmpty(firstSub))
                    {
                        routeName = firstSub + "." + routeName;
                        domain = firstSub + "." + domain;
                    }
                }
                else
                {
                    string desiredSub = (subParam == "dev") ? "dev" : sub;
                    routeName = desiredSub + "." + routeName;
                    domain = host;
                }
  
                try
                {
                    rightUrl = url.RouteUrl(routeName, routeValues);
                }
                catch (ArgumentException)
                {
  
                }
  
                string absoluteAction = string.Format("{0}://{1}{2}", url.RequestContext.HttpContext.Request.Url.Scheme, domain, rightUrl);
  
                if (!string.IsNullOrEmpty(subParam) && subParam != "dev")
                {
                    absoluteAction = absoluteAction.SetUrlParameter("sub", sub);
                }
  
                return absoluteAction;
            }
            public static string GetUrlParameters(this string url)
            {
                Uri uri = new Uri(url);
                var queryParts = HttpUtility.ParseQueryString(uri.Query);
                return queryParts.ToString();
            }
  
            public static string SetUrlParameter(this string url, string paramName, string value)
            {
                return new Uri(url).SetParameter(paramName, value).ToString();
            }
  
            public static Uri SetParameter(this Uri url, string paramName, string value)
            {
                var queryParts = HttpUtility.ParseQueryString(url.Query);
                queryParts[paramName] = value;
                return new Uri(url.AbsoluteUriExcludingQuery() + '?' + queryParts.ToString());
            }
  
            public static string AbsoluteUriExcludingQuery(this Uri url)
            {
                return url.AbsoluteUri.Split('?').FirstOrDefault() ?? String.Empty;
            }
            public static string GetSubdomain(this string host)
            {
                if (host.IndexOf(":") >= 0)
                    host = host.Substring(0, host.IndexOf(":"));
  
                Regex tldRegex = new Regex(@"\.[a-z]{2,3}\.[a-z]{2}$");
                host = tldRegex.Replace(host, "");
                tldRegex = new Regex(@"\.[a-z]{2,4}$");
                host = tldRegex.Replace(host, "");
  
                if (host.Split('.').Length > 1)
                    return host.Substring(0, host.IndexOf("."));
                else
                    return string.Empty;
            }
        }
    }
  

The source can be found here.

You can view a live demo here.