How to get HealthVault to work with multiple ApplicationID in same application

Question

We may never know why Microsoft decided to limit developers by making HealthVault applications constrained to a single web/app.config entry for a HealthVault application. However I need to be able to make 2 (or more) HealthVault ApplicationID’s work with one ASP.NET website? I’m looking for an effective and reliable way to do this.

I won’t go into the details of the reasoning behind 2 different HealthVault applications, but other than to say we need it to work. I still cannot login correctly with MSDN Forums (think infinite redirection sign in loop) so I am hoping for a post here that will help me.

I did contact a HealthVault developer on how to achieve this however the developer gave a suggestion that I don’t believe would be reliable (if I’m wrong let me know).

The developer’s suggestion was to do the following in code when you needed to connect to HealthVault, but prior to connecting:

ConfigurationSettings.AppSettings[“ApplicationId”] = “[YOUR APP ID]”;

The problem is that this is a static property and I do see this as an issue as our web application will have different users accessing both HealthVault applications at the same time. Does anyone have any suggestions to make 2 (or more) HealthVault ApplicationID’s work with one ASP.NET website? I’m looking for an effective and reliable way to do this.

Answer 1

There is a way to dynamically switch app ids on runtime. Both applications must be created, both certificates must be installed. Few things to keep in mind. For every authenticated connection, user will be granted a token (aka wctoken).

This token is consumed when user is redirect back from Live ID (in case live id is used...) by your redirect.aspx page (assuming your redirect page inherits from HealthServiceActionPage.

This means that everytime you switch applications, you must redirect user back to Live ID with new app id to receive new token.

Here is code sample that can be user to dynamically change settings:

public class ConfigurationManager : HealthWebApplicationConfiguration
{
    private string appid;
    public ConfigurationManager(string appid)
    {
        this.appid = appid;
    }
    public override Guid ApplicationId
    {
        get
        {
           return AppManager.Current.GetCurrentAppId(this.appid);
        }
    }
}

public class AppManager
{
    private static readonly Object lck = new Object();

    public Guid? App;

    public static AppManager Current
    {
        get
        {
            AppManager mgr = null;

            if (_current == null)
            {
                lock (lck)
                {
                    mgr = new AppManager();
                }
            }

            return mgr;
        }
    }

    private static AppManager _current;

    public Guid GetCurrentAppId(string id)
    {
        return new Guid(id);
    }
}

Usage:

ConfigurationManager cm = new ConfigurationManager(your-app-id-here);
HealthWebApplicationConfiguration.Current = cm;