WebApi Switch Connectionstring related on HeaderValue - Request is null - entity-framework

Question

We have different Customers and each of them own a Database.
the client send an Request with an HttpHeader DatabaseOwner:Samsung
HttpClient client = new HttpClient();
client.DefaultRequestHeaders.Add("DatabaseOwner", "Samsung");
In my ApiController i would like that my Context is based on that Value and connects to the correct Database
public class AuthController : ApiController
{
public CmpContext db { get; set; }
public AuthController(): base()
{
db = new CmpContext(VcsCmpConnectionstring.GetCMPConnectionString(this.Request));
}
// GET api/Auth
public IQueryable<DealerModel> GetDealer()
{
return db.Dealer;
}
public static string GetCMPConnectionString(HttpRequestMessage request)
{
string returnvalue;
if (request.Headers.Contains("DatabaseOwner"))
{
SqlConnectionStringBuilder ConnStringBuilder = new SqlConnectionStringBuilder(ConfigurationManager.ConnectionStrings["CMPContext"].ConnectionString);
ConnStringBuilder.InitialCatalog = "vcs_cmp_" + request.Headers.GetValues("DatabaseOwner").First();
returnvalue = ConnStringBuilder.ToString();
}
else
{
throw new MissingFieldException("Header DatabaseOwneris null");
}
return returnvalue;
}
When i try to get this.Request it is always null
When is Request access able or is there a better way to switch between Databases?
Greetings from Bavaria
Patrick

Answer 1

Request object is only initialized after APIController's Initialize function is called. So you cannot access Request before base.initialize is called. Try doing this:
public class AuthController : ApiController
{
protected override void Initialize(
System.Web.Http.Controllers.HttpControllerContext controllerContext)
{
base.Initialize(controllerContext);
db = new CmpContext(
VcsCmpConnectionstring.GetCMPConnectionString(this.Request));
}
}