EF Core Custom Conventions

MyContext.cs

protected override void OnModelCreating(ModelBuilder modelBuilder)
{
    foreach (var entityType in modelBuilder.Model.GetEntityTypes())
    {
        foreach (var property in entityType.GetProperties())
        {
            var columnName = property.SqlServer().ColumnName;
            if (columnName.Length > 30)
            {
                throw new InvalidOperationException("Column name is greater than 30 characters - " + columnName);
            }
        }
    }
}