Mapping a list of Enums - fluent-nhibernate

Question

I have a table called UserPermissions with a FK to the users table by userId and then a string column for the string value of an enum.
The error I am seeing is NHibernate.MappingException: An association from the table UserPermissions refers to an unmapped class: GotRoleplay.Core.Domain.Model.Permission
My Permission Enum:
public enum Permission
{
[StringValue("Add User")]
AddUser,
[StringValue("Edit User")]
EditUser,
[StringValue("Delete User")]
DeleteUser,
[StringValue("Add Content")]
AddContent,
[StringValue("Edit Content")]
EditContent,
[StringValue("Delete Content")]
DeleteContent,
}
The property in my User class:
public virtual IList<Permission> Permissions { get; set; }
My database table:
CREATE TABLE dbo.UserPermissions
(
UserPermissionId int IDENTITY(1,1) NOT NULL,
UserId int NOT NULL,
PermissionName varchar (50) NOT NULL,
CONSTRAINT PK_UserPermissions PRIMARY KEY CLUSTERED (UserPermissionId),
CONSTRAINT FK_UserPermissions_Users FOREIGN KEY (UserId) REFERENCES Users(UserId),
CONSTRAINT U_User_Permission UNIQUE(UserId, PermissionName)
)
My attempt at mapping the permissions property of my user object:
HasManyToMany(x => x.Permissions)
.WithParentKeyColumn("UserId")
.WithChildKeyColumn("PermissionName")
.WithTableName("UserPermissions")
.LazyLoad();
What am I doing wrong that it can't map the permission to a list of enum values?

Answer 1

here is the way which worked for me
HasMany(x => x.Licences)
.WithTableName("DriverLicence")
.AsElement("Level").AsBag();
look here for more information answer

Answer 2

You need to specify the type so that NHibernate can convert the value in the table to a member of the Permission enum.
HasManyToMany(x => x.Permissions)
.WithParentKeyColumn("UserId")
.WithChildKeyColumn("PermissionName")
.WithTableName("UserPermissions")
.LazyLoad()
.CustomTypeIs(typeof(Permission));
Edited to add:
I'm sorry, I should have noticed that you had this as ManyToMany. That's not possible: You can't have a Users collection (other side of m:m) hanging off an enum. You need to define this as 1:m or create a Permission table and class and map that as m:m.

Answer 3

I thought I would post the code that I chose for my solution. It's only a workaround. I wish Fluent would support Enum lists, but until it does, here's a possible solution:
The Enum - This is my enum, your standard enum.
public enum PermissionCode
{
//site permissions 1-99
ViewUser = 1,
AddUser = 2,
EditUser = 3,
DeleteUser = 4
}
Next, I have my Permission class.
public class Permission
{
public virtual int PermissionId { get; set; }
public virtual string PermissionName { get; set; }
public virtual PermissionCode PermissionCode
{
get
{
return (PermissionCode)PermissionId;
}
}
}
As you can see, I have an ID and a name, and then a property that converts the Id into my PermissionCode enum.
The mapping looks like this:
public class PermissionMap : ClassMap<Permission>
{
public PermissionMap()
{
WithTable("Permissions");
Id(x => x.PermissionId).GeneratedBy.Identity();
Map(x => x.PermissionName);
}
}
Since the PermissionCode property is derived, we don't do anything in the mapping.
My Table structure behind the mapping looks like this:
CREATE TABLE dbo.Permissions
(
PermissionId int NOT NULL,
PermissionName varchar (50) NOT NULL,
CONSTRAINT PK_Permissions PRIMARY KEY CLUSTERED (PermissionId)
)
If you wanted to use the name instead of the integer value, with some slight modifications you can. It depends on your personal preferences.