v0.0.127

sq/converter.go

@@ -0,0 +1,91 @@
+package sq
+
+import (
+	"errors"
+	"fmt"
+	"gogs.mikescher.com/BlackForestBytes/goext/langext"
+	"time"
+)
+
+//TODO UNFINISHED
+// this is not finished
+// idea was that we can register converter in the database struct
+// they get inherited from the transactions
+// and when marshallingunmarshaling (sq.Query | sq.QueryAll)
+// or marshaling (sq.InsertSingle)
+// the types get converter automatically...
+
+type DBTypeConverter interface {
+	ModelTypeString() string
+	DBTypeString() string
+	ModelToDB(v any) (any, error)
+	DBToModel(v any) (any, error)
+}
+
+var ConverterBoolToBit = NewDBTypeConverter[bool, int](func(v bool) (int, error) {
+	return langext.Conditional(v, 1, 0), nil
+}, func(v int) (bool, error) {
+	if v == 0 {
+		return false, nil
+	}
+	if v == 1 {
+		return true, nil
+	}
+	return false, errors.New(fmt.Sprintf("invalid valud for boolean: '%d'", v))
+})
+
+var ConverterTimeToUnixMillis = NewDBTypeConverter[time.Time, int64](func(v time.Time) (int64, error) {
+	return v.UnixMilli(), nil
+}, func(v int64) (time.Time, error) {
+	return time.UnixMilli(v), nil
+})
+
+var ConverterOptTimeToUnixMillis = NewDBTypeConverter[*time.Time, *int64](func(v *time.Time) (*int64, error) {
+	if v == nil {
+		return nil, nil
+	}
+	return langext.Ptr(v.UnixMilli()), nil
+}, func(v *int64) (*time.Time, error) {
+	if v == nil {
+		return nil, nil
+	}
+	return langext.Ptr(time.UnixMilli(*v)), nil
+})
+
+type dbTypeConverterImpl[TModelData any, TDBData any] struct {
+	dbTypeString    string
+	modelTypeString string
+	todb            func(v TModelData) (TDBData, error)
+	tomodel         func(v TDBData) (TModelData, error)
+}
+
+func (t *dbTypeConverterImpl[TModelData, TDBData]) ModelTypeString() string {
+	return t.modelTypeString
+}
+
+func (t *dbTypeConverterImpl[TModelData, TDBData]) DBTypeString() string {
+	return t.dbTypeString
+}
+
+func (t *dbTypeConverterImpl[TModelData, TDBData]) ModelToDB(v any) (any, error) {
+	if vv, ok := v.(TModelData); ok {
+		return t.todb(vv)
+	}
+	return nil, errors.New(fmt.Sprintf("Unexpected value in DBTypeConverter, expected '%s', found '%T'", t.modelTypeString, v))
+}
+
+func (t *dbTypeConverterImpl[TModelData, TDBData]) DBToModel(v any) (any, error) {
+	if vv, ok := v.(TDBData); ok {
+		return t.tomodel(vv)
+	}
+	return nil, errors.New(fmt.Sprintf("Unexpected value in DBTypeConverter, expected '%s', found '%T'", t.dbTypeString, v))
+}
+
+func NewDBTypeConverter[TModelData any, TDBData any](todb func(v TModelData) (TDBData, error), tomodel func(v TDBData) (TModelData, error)) DBTypeConverter {
+	return &dbTypeConverterImpl[TModelData, TDBData]{
+		dbTypeString:    fmt.Sprintf("%T", *new(TDBData)),
+		modelTypeString: fmt.Sprintf("%T", *new(TModelData)),
+		todb:            todb,
+		tomodel:         tomodel,
+	}
+}