void Initialize()
{
if (_memberHandlers is null)
{
InitializeCore();
}
void InitializeCore()
{
var pgType = (PostgresCompositeType)PostgresType;
_memberHandlers = CreateMemberHandlers(pgType, _typeMapper, _nameTranslator);
_constructorHandler = CreateConstructorHandler(pgType, _typeMapper, _nameTranslator);
_constructor = _constructorHandler is null
? Expression
.Lambda <Func <T> >(Expression.New(typeof(T)))
.Compile()
: null;
}
}
static CompositeMemberHandler <T>[] CreateMemberHandlers(PostgresCompositeType pgType, ConnectorTypeMapper typeMapper, INpgsqlNameTranslator nameTranslator)
{
var pgFields = pgType.Fields;
var clrType = typeof(T);
var clrMemberHandlers = new CompositeMemberHandler <T> [pgFields.Count];
var clrMemberHandlerCount = 0;
var clrMemberHandlerType = IsValueType <T> .Value
? typeof(CompositeStructMemberHandler <,>)
: typeof(CompositeClassMemberHandler <,>);
foreach (var clrProperty in clrType.GetProperties(BindingFlags.Instance | BindingFlags.Public))
{
CreateMemberHandler(clrProperty, clrProperty.PropertyType);
}
foreach (var clrField in clrType.GetFields(BindingFlags.Instance | BindingFlags.Public))
{
CreateMemberHandler(clrField, clrField.FieldType);
}
if (clrMemberHandlerCount != pgFields.Count)
{
var notMappedFields = string.Join(", ", clrMemberHandlers
.Select((member, memberIndex) => member == null ? $"'{pgFields[memberIndex].Name}'" : null)
.Where(member => member != null));
throw new InvalidOperationException($"PostgreSQL composite type {pgType.DisplayName} contains fields {notMappedFields} which could not match any on CLR type {clrType.Name}");
}
return(clrMemberHandlers);
void CreateMemberHandler(MemberInfo clrMember, Type clrMemberType)
{
var attr = clrMember.GetCustomAttribute <PgNameAttribute>();
var name = attr?.PgName ?? nameTranslator.TranslateMemberName(clrMember.Name);
for (var pgFieldIndex = pgFields.Count - 1; pgFieldIndex >= 0; --pgFieldIndex)
{
var pgField = pgFields[pgFieldIndex];
if (pgField.Name != name)
{
continue;
}
if (clrMemberHandlers[pgFieldIndex] != null)
{
throw new AmbiguousMatchException($"Multiple class members are mapped to the '{pgField.Name}' field.");
}
if (!typeMapper.TryGetByOID(pgField.Type.OID, out var handler))
{
throw new NpgsqlException($"PostgreSQL composite type {pgType.DisplayName} has field {pgField.Type.DisplayName} with an unknown type (OID = {pgField.Type.OID}).");
}
clrMemberHandlerCount++;
clrMemberHandlers[pgFieldIndex] = (CompositeMemberHandler <T>)Activator.CreateInstance(
clrMemberHandlerType.MakeGenericType(clrType, clrMemberType),
BindingFlags.Instance | BindingFlags.Public,
binder: null,
args: new object[] { clrMember, pgField.Type, handler },
culture: null) !;
break;
}
}
}