public TenantedDbContext(DbContextOptions <TenantedDbContext> options,
IConfiguration config,
ITenantProvider tenantProvider)
: base(options)
{
_tenant = tenantProvider?.GetCurrentRequestTenant() ?? throw new ArgumentNullException(nameof(tenantProvider));
_connectionString = config.GetTenantedConnectionString(_tenant.Id) ?? throw new ArgumentNullException("Unable to source template connection string from config.");
}