Commerce Starter Kit - ASP.NET 2.0 PayPal

Extending the ASP.NET 2.0 PayPal Commerce Starter Kit - ReferralProvider for Tracking Online Store Referrals

Dave Hayden — Sun, 20 Nov 2005 13:29:00 GMT

The Commerce Starter Kit ( http://www.commercestarterkit.org/ ) provides a simple and effective solution to sell items on the Internet. The online store supports PayPal, ASP.NET 2.0, and the new Provider Model in the .NET 2.0 Framework.

Previously I created an InventoryProvider for the Commerce Starter Kit which you can read about in the following post:

Extending the ASP.NET 2.0 PayPal Commerce Starter Kit - InventoryProvider for Inventory Management

Now I would like to talk about a ReferralProvider for the Commerce Starter Kit. You can read all my posts on the Commerce Starter Kit in the following category:

Commerce Starter Kit - ASP.NET 2.0 PayPal

ReferralProvider for Tracking Online Store Referrals

One of the features not included in the original design is a simple ReferralProvider that tracks referrals to your online store. As an online retailer you often want to know how people are finding your online store. Is someone linking to your store or are they finding you via the search engines? By tracking your online referrals you are able to answer these questions as well as make better decisions on how to market your online store.

Create an HttpModule - ReferralModule

One of the ways you can track referrals to your website is by creating an HttpModule that subscribes to the Global BeginRequest Event. This event is fired upon each HTTP Request to your website. When you find a referral from another website, you can send the referring URL and the target URL to the ReferralManager which will delegate the responsibility of inserting it to the proper provider ( in this case SqlReferralProvider ).

/// <summary>
/// Summary description for ReferralModule
/// </summary>
public class ReferralModule : IHttpModule
{
    public ReferralModule()
    {
    }

    #region IHttpModule Members

    public void Dispose()
    {
    }

    public void Init(HttpApplication context)
    {
        context.BeginRequest +=
            new EventHandler(context_BeginRequest);
    }

    #endregion

    void context_BeginRequest(object sender, EventArgs e)
    {
        HttpApplication app = sender as HttpApplication;

        if (app.Context == null)
            return;

        HttpContext context = app.Context;

        if (context.Request.UrlReferrer == null ||
                string.IsNullOrEmpty(context.Request.
                UrlReferrer.ToString()))
            return;

        if (context.Request.UrlReferrer.Host.
                Equals(context.Request.Url.Host))
            return;

        ReferralManager.InsertReferral(context.Request.
            UrlReferrer.ToString(), context.Request.Url.
            ToString());
    }
}

ReferralManager - Business Layer Manager Handling UI Requests

The HttpModule passes the request to the ReferralManager that does nothing but hand off the referral information to the ReferralProvider registered in the Web.Config file.

/// <summary>
/// Summary description for ReferralManager
/// </summary>
public class ReferralManager
{
    /// <summary>
    /// Gets all the referrals in the database
    /// </summary>
    /// <returns>IDataReader</returns>
    public static IDataReader GetReferrals()
    {
        return Commerce.Providers.ReferralProvider.
            Instance.GetReferrals();
    }

    /// <summary>
    /// Insert a referral in the database
    /// </summary>
    /// <param name="referringUrl">From Url</param>
    /// <param name="url">To Url</param>
    public static void InsertReferral(string referringUrl,
                                        string url)
    {
        Commerce.Providers.ReferralProvider.Instance.
            InsertReferral(referringUrl, url);
    }

    /// <summary>
    /// Delete all referrals in the database
    /// </summary>
    public static void DeleteAll()
    {
        Commerce.Providers.ReferralProvider.Instance.
            DeleteAllReferrals();
    }

    /// <summary>
    /// Delete all referrals in the database before a date.
    /// </summary>
    /// <param name="referralDate">Delete referrals
            before this date.</param>
    public static void DeleteBefore(DateTime referralDate)
    {
        Commerce.Providers.ReferralProvider.Instance.
            DeleteReferralsBefore(referralDate);
    }
}

SqlReferralProvider - Concrete ReferralProvider Tracking Online Store Referrals

The SqlReferralProvider stores and manages the referral information in a table, called CMRC_Referrals, via a number of stored procedures.

SqlReferralProvider provides a Count field that shows a rolling count of the number of referrals from a specific URL so that you can get some sort of idea as to the amount of traffic from a specific URL. This allows you to identify your most active referrers. This rolling count is handled in the Insert Stored Procedure to keep database calls to a minimum. Below is a snippet of SqlReferralProvider responsible for inserting the referral.

As mentioned before, the Commerce Starter Kit uses the Data Access Application Block ( DAAB ) 2.0 to help with data access layer functionality. Here I am calling the stored procedure, CMRC_REFERRALS_Insert, with the referringURL and target URL.

public override void InsertReferral
        (string referringUrl, string url)
{
    SqlParameter[] parameters =
        new SqlParameter[2];

    SqlParameter referringUrlParameter =
        new SqlParameter("@ReferringUrl",
        SqlDbType.VarChar, 255);
    referringUrlParameter.Value = referringUrl;
    parameters[0] = referringUrlParameter;

    SqlParameter urlParameter =
        new SqlParameter("@Url", SqlDbType.VarChar,
        255);
    urlParameter.Value = url;
    parameters[1] = urlParameter;

    SqlHelper.ExecuteNonQuery(_connectionString,
        CommandType.StoredProcedure,
        "CMRC_REFERRALS_Insert", parameters);
}

Conclusion

The ReferralProvider extension to the ASP.NET 2.0 and PayPal Commerce Starter Kit provides a simple and effective solution for tracking referrals to your online store. You can modify the existing code or create a new provider for your own online store. Extremely busy stores will want to provide a more scalable solution that queues each request for insertion at a later time.

You can download the source code here.

Written by David Hayden ( ASP.NET Developer, Blog )

Extending the ASP.NET 2.0 PayPal Commerce Starter Kit - InventoryProvider for Inventory Management

Dave Hayden — Sun, 13 Nov 2005 22:24:00 GMT

I downloaded the ASP.NET 2.0 PayPal Commerce Starter Kit (CSK) Friday for kicks and ended up creating a new provider, called InventoryProvider, that provides the basis for a more functional and feature-rich inventory management system. I say "provides the basis," because my immediate intentions were to do the minimal amount of work possible to have CSK use the provider and then add new features in increments later.

AmountOnHand

Currently, CSK fulfills its inventory management via an AmountOnHand field in the Products Table.

This is fine for a starter kit and simple needs, but I thought I would provide the foundation for extending these needs a bit further using what exists today.

InventoryProvider

CSK uses the Provider Model to abstract the functionality needed by the website from the actual concrete classes that provide it. It has providers to handle the product catalog, shopping cart, orders, tax calculations, etc. I followed this model by creating an InventoryProvider to provide functionality and features associated with Inventory Management.

Product Detail Page and Inventory Manager

One of the places where CSK uses the AmountOnHand field associated with a product is on the Product Detail Page where it decides if the Add To Cart Link and Out of Stock Label should be displayed. I no longer want to access that information directly, but have the page call the InventoryManager which is responsible for handling Inventory Management needs.

The InventoryManager sits right with the other managers used by CSK.

Here is a stripped down version of the InventoryManager showing you the functionality in question. I am following the same style as the other manager classes in CSK:

public class InventoryManager
{

    /// 
    /// Get product quantity on hand
    /// 
    /// 
    /// 
    public static int GetAmountOnHand(int productID)
    {
        return Commerce.Providers.
            InventoryProvider.Instance.
                  GetQtyInStock(productID);
    }
}

Simplest Thing Possible - ReUse Existing Functionality in CSK

Although my needs in the future will require a bit more functionality, I don't want to be bothered with that at this point. I just need to get InventoryManager integrated into the UI to abstract the idea of AmountOnHand from Product while still using the existing functionality. Hence, I just stole the code from the SqlCatalogProvider to load a product and return the value in the AmountOnHand Field.

I contributed about 4 lines of code below, which is the GetQtyInStock method implemented in SqlInventoryProvider. Note that the code is far from optimized and just serves the near term. As you can see, CSK uses the Microsoft Data Access Application Block for its data access needs.

public override int GetQtyInStock(int productID)
{
    int qtyInStock = 0;

    SqlDataReader rdr = null;
    
    //Define the parameters
    SqlParameter[] paramArray = new SqlParameter[]
    {
        new SqlParameter("@ProductID", SqlDbType.Int,
            0, ParameterDirection.Input, true, 10, 0,
            null, DataRowVersion.Current, productID),
    };
    
    try
    {
        //Fill the dataset using the connection
        // string from the db base class
        rdr = Microsoft.ApplicationBlocks.Data.SqlHelper.
              ExecuteReader (_connectionString, CommandType.
              StoredProcedure, "CMRC_PRODUCTS_Get",
              paramArray);
            
        if (rdr.Read())
        {
            int ordinal = rdr.GetOrdinal("AmountOnHand");
            qtyInStock = rdr.GetInt32(ordinal);
        }
    }
    catch (SqlException x)
    {
        string sException = "Error Executing
            CMRC_PRODUCTS_Get: \r\n";
        foreach (SqlParameter p in paramArray)
        {
            sException += p.ParameterName + "=" +
               p.Value + "\r\n";
        }
        throw new Exception(sException, x);

    }

    return qtyInStock;

}

Web.Config Provider Stuff

With all Provider Model implementations, you end up putting information into Web.Config to create this pluggable environment. I have no other needs than the basics. I used the current providers in CSK as a template for the InventoryProvider:

<configSections>
    <section name="CommerceInventoryProvider"
    type="Commerce.Providers.
      InventoryProviderConfigurationHandler,
    Commerce.InventoryProvider"/>
    
configSections>
<CommerceInventoryProvider defaultProvider=
       "SqlInventoryProvider">
    <providers>
          <clear/>
          <add name="SqlInventoryProvider"
        type="Commerce.Providers.SqlInventoryProvider,
        Commerce.InventoryProvider"
        connectionStringName="CommerceTemplate" />
    providers>
CommerceInventoryProvider>

Conclusion

Hopefully this sheds some light on how easy it is to extend the ASP.NET 2.0 PayPal Commerce Starter Kit. The InventoryProvider mentioned in this article can be extended to provide quite a bit of additional functionality than the current implementation.

Written by David Hayden ( .NET Developer / Blog )

ASP.NET 2.0 Online Store Starter Kit - Commerce Starter Kit (CSK) with PayPal Support

Dave Hayden — Fri, 11 Nov 2005 11:32:00 GMT

Another ASP.NET 2.0 Starter Kit hits the scenes. This one is an online store starter kit that supports PayPal Website Payments Standard and Pro as the payment engine.

Looks as though it uses the Provider Model pretty heavily according to a forum message. It uses SQL Server Express, but there are some SQL Server 2005 upsizer scripts if you don't want to use SQL Server Express. I think I even see some CodeSmith templates in there to help with generating code for Microsoft DAAB and Stored Procedures. By the way, all the source code is in C# and I am sure they would love someone to port it to VB.

No better way to learn then looking through other people's code ;)

Some marketing stuff from the website:

“The Commerce Starter Kit offers .NET developers of all skill levels the ability to create an e-commerce site quickly and efficiently. The project is built in C# and takes advantage of features of the Microsoft.NET Framework 2.0. It also supports PayPal Website Payments Standard and Pro as the payment engine.

With this site, you can quickly get up to speed using all of these pre-built features:

Product catalog & shopping cart
Product inventory and order Management
Credit card processing via PayPal Website
Payments Standard and Pro
Login and anonymous shopping
Simple shipping and sales tax
Customer purchase history
Usage logs

Technical Requirements:

Visual Studio 2005
SQL Server 2005 Express
PayPal Business account required for seller. Customers can purchase without a PayPal account“

Learn more here.

Posted by David Hayden