StructureMap-为多租户Web应用程序上的每个数据库初始化实体框架

Question

We are developing a multi tenanted ASP.NET MVC web application. Each tenant has their own database. Data access is managed by the entity framework. StructureMap is being used as the IoC container. The entity framework data context has been setup with http request scope. For each request the tenant is worked out and StructureMap returns a new instance of the entity framework data context and repository classes.

In the start up class of the web app (implementation of IProcessHostPreloadClient) I would like to initialise the entity framework - I would need to loop around and create a new instance of the datacontext for each configured tenant. What is the best way of going about this? StructureMap would return the same data context as it has been setup to cache with http/thread scope.

Thanks, Harsha

Answer 1

If you just want to vary the connection string based on the tenant, the following should work:

For<Tenant>().Use(c => c.GetInstance<TenantFactory>().CreateTenant());
For<DbContext>().Use(c => new DbContext(
    ConfigurationManager.ConnectionStrings[c.GetInstance<Tenant>().ConnectionName]
        .ConnectionString));

The Tenant class should hold the current tenant connection string name and the TenantFactory would create the appropriate Tenant unsing whatever method you use for determining the connection string.

If it's a more extensive variation, a multi-container approach might be better.