Import to pgx main repo in pgtype subdir

2021-12-04 13:07:54 -06:00
parent 550cc7b529
commit 44214b7854
237 changed files with 0 additions and 0 deletions
@@ -0,0 +1,227 @@
+package pgtype
+
+import (
+	"database/sql/driver"
+	"encoding/binary"
+	"fmt"
+	"time"
+
+	"github.com/jackc/pgio"
+)
+
+const pgTimestampFormat = "2006-01-02 15:04:05.999999999"
+
+// Timestamp represents the PostgreSQL timestamp type. The PostgreSQL
+// timestamp does not have a time zone. This presents a problem when
+// translating to and from time.Time which requires a time zone. It is highly
+// recommended to use timestamptz whenever possible. Timestamp methods either
+// convert to UTC or return an error on non-UTC times.
+type Timestamp struct {
+	Time             time.Time // Time must always be in UTC.
+	Valid            bool
+	InfinityModifier InfinityModifier
+}
+
+// Set converts src into a Timestamp and stores in dst. If src is a
+// time.Time in a non-UTC time zone, the time zone is discarded.
+func (dst *Timestamp) Set(src interface{}) error {
+	if src == nil {
+		*dst = Timestamp{}
+		return nil
+	}
+
+	if value, ok := src.(interface{ Get() interface{} }); ok {
+		value2 := value.Get()
+		if value2 != value {
+			return dst.Set(value2)
+		}
+	}
+
+	switch value := src.(type) {
+	case time.Time:
+		*dst = Timestamp{Time: time.Date(value.Year(), value.Month(), value.Day(), value.Hour(), value.Minute(), value.Second(), value.Nanosecond(), time.UTC), Valid: true}
+	case *time.Time:
+		if value == nil {
+			*dst = Timestamp{}
+		} else {
+			return dst.Set(*value)
+		}
+	case InfinityModifier:
+		*dst = Timestamp{InfinityModifier: value, Valid: true}
+	default:
+		if originalSrc, ok := underlyingTimeType(src); ok {
+			return dst.Set(originalSrc)
+		}
+		return fmt.Errorf("cannot convert %v to Timestamp", value)
+	}
+
+	return nil
+}
+
+func (dst Timestamp) Get() interface{} {
+	if !dst.Valid {
+		return nil
+	}
+	if dst.InfinityModifier != None {
+		return dst.InfinityModifier
+	}
+	return dst.Time
+}
+
+func (src *Timestamp) AssignTo(dst interface{}) error {
+	if !src.Valid {
+		return NullAssignTo(dst)
+	}
+
+	switch v := dst.(type) {
+	case *time.Time:
+		if src.InfinityModifier != None {
+			return fmt.Errorf("cannot assign %v to %T", src, dst)
+		}
+		*v = src.Time
+		return nil
+	default:
+		if nextDst, retry := GetAssignToDstType(dst); retry {
+			return src.AssignTo(nextDst)
+		}
+		return fmt.Errorf("unable to assign to %T", dst)
+	}
+}
+
+// DecodeText decodes from src into dst. The decoded time is considered to
+// be in UTC.
+func (dst *Timestamp) DecodeText(ci *ConnInfo, src []byte) error {
+	if src == nil {
+		*dst = Timestamp{}
+		return nil
+	}
+
+	sbuf := string(src)
+	switch sbuf {
+	case "infinity":
+		*dst = Timestamp{Valid: true, InfinityModifier: Infinity}
+	case "-infinity":
+		*dst = Timestamp{Valid: true, InfinityModifier: -Infinity}
+	default:
+		tim, err := time.Parse(pgTimestampFormat, sbuf)
+		if err != nil {
+			return err
+		}
+
+		*dst = Timestamp{Time: tim, Valid: true}
+	}
+
+	return nil
+}
+
+// DecodeBinary decodes from src into dst. The decoded time is considered to
+// be in UTC.
+func (dst *Timestamp) DecodeBinary(ci *ConnInfo, src []byte) error {
+	if src == nil {
+		*dst = Timestamp{}
+		return nil
+	}
+
+	if len(src) != 8 {
+		return fmt.Errorf("invalid length for timestamp: %v", len(src))
+	}
+
+	microsecSinceY2K := int64(binary.BigEndian.Uint64(src))
+
+	switch microsecSinceY2K {
+	case infinityMicrosecondOffset:
+		*dst = Timestamp{Valid: true, InfinityModifier: Infinity}
+	case negativeInfinityMicrosecondOffset:
+		*dst = Timestamp{Valid: true, InfinityModifier: -Infinity}
+	default:
+		tim := time.Unix(
+			microsecFromUnixEpochToY2K/1000000+microsecSinceY2K/1000000,
+			(microsecFromUnixEpochToY2K%1000000*1000)+(microsecSinceY2K%1000000*1000),
+		).UTC()
+		*dst = Timestamp{Time: tim, Valid: true}
+	}
+
+	return nil
+}
+
+// EncodeText writes the text encoding of src into w. If src.Time is not in
+// the UTC time zone it returns an error.
+func (src Timestamp) EncodeText(ci *ConnInfo, buf []byte) ([]byte, error) {
+	if !src.Valid {
+		return nil, nil
+	}
+	if src.Time.Location() != time.UTC {
+		return nil, fmt.Errorf("cannot encode non-UTC time into timestamp")
+	}
+
+	var s string
+
+	switch src.InfinityModifier {
+	case None:
+		s = src.Time.Truncate(time.Microsecond).Format(pgTimestampFormat)
+	case Infinity:
+		s = "infinity"
+	case NegativeInfinity:
+		s = "-infinity"
+	}
+
+	return append(buf, s...), nil
+}
+
+// EncodeBinary writes the binary encoding of src into w. If src.Time is not in
+// the UTC time zone it returns an error.
+func (src Timestamp) EncodeBinary(ci *ConnInfo, buf []byte) ([]byte, error) {
+	if !src.Valid {
+		return nil, nil
+	}
+	if src.Time.Location() != time.UTC {
+		return nil, fmt.Errorf("cannot encode non-UTC time into timestamp")
+	}
+
+	var microsecSinceY2K int64
+	switch src.InfinityModifier {
+	case None:
+		microsecSinceUnixEpoch := src.Time.Unix()*1000000 + int64(src.Time.Nanosecond())/1000
+		microsecSinceY2K = microsecSinceUnixEpoch - microsecFromUnixEpochToY2K
+	case Infinity:
+		microsecSinceY2K = infinityMicrosecondOffset
+	case NegativeInfinity:
+		microsecSinceY2K = negativeInfinityMicrosecondOffset
+	}
+
+	return pgio.AppendInt64(buf, microsecSinceY2K), nil
+}
+
+// Scan implements the database/sql Scanner interface.
+func (dst *Timestamp) Scan(src interface{}) error {
+	if src == nil {
+		*dst = Timestamp{}
+		return nil
+	}
+
+	switch src := src.(type) {
+	case string:
+		return dst.DecodeText(nil, []byte(src))
+	case []byte:
+		srcCopy := make([]byte, len(src))
+		copy(srcCopy, src)
+		return dst.DecodeText(nil, srcCopy)
+	case time.Time:
+		*dst = Timestamp{Time: src, Valid: true}
+		return nil
+	}
+
+	return fmt.Errorf("cannot scan %T", src)
+}
+
+// Value implements the database/sql/driver Valuer interface.
+func (src Timestamp) Value() (driver.Value, error) {
+	if !src.Valid {
+		return nil, nil
+	}
+
+	if src.InfinityModifier != None {
+		return src.InfinityModifier.String(), nil
+	}
+	return src.Time, nil
+}