diamond-orm/model.go

67 lines
2.0 KiB
Go

package orm
import (
"reflect"
)
// Model - an intermediate representation of a Go struct
type Model struct {
Name string // the name, almost always the name of the underlying Type
Type reflect.Type // the Go type this model represents
Relationships map[string]*Relationship // a mapping of struct field names to Relationship pointers
IDField string // the name of the field containing this model's ID
Fields map[string]*Field // mapping of struct field names to Field pointers
FieldsByColumnName map[string]*Field // mapping of database column names to Field pointers
TableName string // the name of the table where this model's data is stored. defaults to a snake_cased version of the type/struct name if not provided explicitly via tag
embeddedIsh bool // INTERNAL - whether this model is: 1) contained in another type and 2) wasn't explicitly passed to the `Models` method (i.e., it can't "exist" on its own)
}
func (m *Model) addField(field *Field) {
field.Model = m
m.Fields[field.Name] = field
m.FieldsByColumnName[field.ColumnName] = field
}
const (
documentField = "Document"
createdField = "Created"
modifiedField = "Modified"
)
func (m *Model) docField() *Field {
return m.Fields[documentField]
}
func (m *Model) idField() *Field {
return m.Fields[m.IDField]
}
func (m *Model) getPrimaryKey(val reflect.Value) (string, any) {
colField := m.Fields[m.IDField]
if colField == nil {
return "", nil
}
colName := colField.ColumnName
wasPtr := false
if val.Kind() == reflect.Ptr {
if val.IsNil() {
return "", nil
}
val = val.Elem()
wasPtr = true
}
if val.IsZero() && wasPtr {
return "", nil
}
idField := val.FieldByName(m.IDField)
if idField.IsValid() {
return colName, idField.Interface()
}
return "", nil
}
func (m *Model) needsPrimaryKey(val reflect.Value) bool {
_, pk := m.getPrimaryKey(val)
return pk == nil || reflect.ValueOf(pk).IsZero()
}