So, I have two main objects, Member and Guild. One Member can own a Guild and one Guild can have multiple Members.
I have the Members class in a separate DbContext and separate class library. I plan to reuse this class library in multiple projects and to help differentiate, I set the database schema to be "acc". I have tested this library extensively and can add, delete, and update Members in the acc.Members table.
The Guild class is as such:
public class Guild
{
public Guild()
{
Members = new List<Member>();
}
public int ID { get; set; }
public int MemberID { get; set; }
public virtual Member LeaderMemberInfo { get; set; }
public string Name { get; set; }
public virtual List<Member> Members { get; set; }
}
with a mapping of:
internal class GuildMapping : EntityTypeConfiguration<Guild>
{
public GuildMapping()
{
this.ToTable("Guilds", "dbo");
this.HasKey(t => t.ID);
this.Property(t => t.MemberID);
this.HasRequired(t => t.LeaderMemberInfo).WithMany().HasForeignKey(t => t.MemberID);
this.Property(t => t.Name);
this.HasMany(t => t.Members).WithMany()
.Map(t =>
{
t.ToTable("GuildsMembers", "dbo");
t.MapLeftKey("GuildID");
t.MapRightKey("MemberID");
});
}
}
But, when I try to create a new Guild, it says that there is no dbo.Members.
I got reference to the Member's EF project and added the mapping to the Members class to the DbContext that the Guild class is a part of. modelBuilder.Configurations.Add(new MemberMapping());
(Not sure if that is the best way.)
This resulted with this error:
{"The member with identity 'GuildProj.Data.EF.Guild_Members' does not exist in the metadata collection.
Parameter name: identity"}
How can I utilize the foreign key between these two tables cross DbContexts and with different database schemas?
UPDATE
I narrowed down the cause of the error. When I create a new guild, I set the guild leader's Member ID to MemberID. This works fine. But, when I then try to add that leader's Member object to the Guild's List of Members (Members), that's what causes the error.
UPDATE 2
Here is the code of how I create the Context that the Guild class is in. (As requested by Hussein Khalil)
public class FSEntities : DbContext
{
public FSEntities()
{
this.Configuration.LazyLoadingEnabled = false;
Database.SetInitializer<FSEntities>(null);
}
public FSEntities(string connectionString)
: base(connectionString)
{
}
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
modelBuilder.Configurations.Add(new GuildMapping());
modelBuilder.Configurations.Add(new KeyValueMappings());
modelBuilder.Configurations.Add(new LocaleMappings());
modelBuilder.Configurations.Add(new MemberMapping());
}
public DbSet<Guild> Guilds { get; set; }
public DbSet<KeyValue> KeyValues { get; set; }
public DbSet<Locale> Locales { get; set; }
}
This is how I am saving it in the repo:
public async Task CreateGuildAsync(Guild guild)
{
using (var context = new FSEntities(_ConnectionString))
{
context.Entry(guild.Members).State = EntityState.Unchanged;
context.Entry(guild).State = EntityState.Added;
await context.SaveChangesAsync();
}
}
FINAL RESOLUTION
So, I had to add mappings to Member
, Role
, and Permission
in DbContext that contained Guild
. I had to add Role and Permission because Member had List<Role> Roles
and each Role had List<Permission> Permissions
.
This got me closer to the solution. I was still getting errors like:
{"The member with identity 'GuildProj.Data.EF.Member_Roles' does not exist in the metadata collection.
Parameter name: identity"}
Here, when you pull Member from the Session
, you get something like this:
System.Data.Entity.DynamicProxies.Member_FF4FDE3888B129E1538B25850A445893D7C49F878D3CD40103BA1A4813EB514C
Entity Framework does not seem to play well with this. Why? I am not sure, but I think it is because ContextM creates a proxy of Member and by cloning the Member into a new Member object, ContextM no longer has association. This, I think, allows ContextG to use the new Member object freely. I tried setting ProxyCreationEnabled = false in my DbContexts, but the Member object being pulled out of Session kept being of type System.Data.Entity.DynamicProxies.Member.
So, what I did was:
Member member = new Member((Member)Session[Constants.UserSession]);
I had to clone each Role
and each Permission
as well inside their respective constructors.
This got me 99% of the way there. I had to alter my repo and how I was saving the Guild
object.
context.Entry(guild.LeaderMemberInfo).State = EntityState.Unchanged;
foreach(var member in guild.Members)
{
context.Entry(member).State = EntityState.Unchanged;
}
context.Entry(guild).State = EntityState.Added;
await context.SaveChangesAsync();
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