protected override void OnModelCreating(ModelBuilder builder)
{
base.OnModelCreating(builder);
builder.Entity <AppUser>().HasMany <Chat>().WithOne(m => m.GetUser_1).OnDelete(DeleteBehavior.Restrict);
builder.Entity <AppUser>().HasMany <Chat>().WithOne(m => m.GetUser_2).OnDelete(DeleteBehavior.Restrict);
builder.Entity <Chat>().HasOne <AppUser>().WithMany(m => m.GetChates_1).OnDelete(DeleteBehavior.Restrict);
builder.Entity <Chat>().HasOne <AppUser>().WithMany(m => m.GetChates_2).OnDelete(DeleteBehavior.Restrict);
RoleSeed.Seed(builder);
UserSeed.Seed(builder);
UserRoleSeed.Seed(builder);
CountrySeed.Seed(builder);
CitySeed.Seed(builder);
}