github.com/mymmsc/gox@v1.3.33/util/uuid/sql.go (about)

     1  // Copyright (C) 2013-2018 by Maxim Bublis <b@codemonkey.ru>
     2  //
     3  // Permission is hereby granted, free of charge, to any person obtaining
     4  // a copy of this software and associated documentation files (the
     5  // "Software"), to deal in the Software without restriction, including
     6  // without limitation the rights to use, copy, modify, merge, publish,
     7  // distribute, sublicense, and/or sell copies of the Software, and to
     8  // permit persons to whom the Software is furnished to do so, subject to
     9  // the following conditions:
    10  //
    11  // The above copyright notice and this permission notice shall be
    12  // included in all copies or substantial portions of the Software.
    13  //
    14  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
    15  // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
    16  // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
    17  // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
    18  // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
    19  // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
    20  // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
    21  
    22  package uuid
    23  
    24  import (
    25  	"database/sql/driver"
    26  	"fmt"
    27  )
    28  
    29  // Value implements the driver.Valuer interface.
    30  func (u UUID) Value() (driver.Value, error) {
    31  	return u.String(), nil
    32  }
    33  
    34  // Scan implements the sql.Scanner interface.
    35  // A 16-byte slice is handled by UnmarshalBinary, while
    36  // a longer byte slice or a string is handled by UnmarshalText.
    37  func (u *UUID) Scan(src interface{}) error {
    38  	switch src := src.(type) {
    39  	case []byte:
    40  		if len(src) == Size {
    41  			return u.UnmarshalBinary(src)
    42  		}
    43  		return u.UnmarshalText(src)
    44  
    45  	case string:
    46  		return u.UnmarshalText([]byte(src))
    47  	}
    48  
    49  	return fmt.Errorf("uuid: cannot convert %T to UUID", src)
    50  }
    51  
    52  // NullUUID can be used with the standard sql package to represent a
    53  // UUID value that can be NULL in the database
    54  type NullUUID struct {
    55  	UUID  UUID
    56  	Valid bool
    57  }
    58  
    59  // Value implements the driver.Valuer interface.
    60  func (u NullUUID) Value() (driver.Value, error) {
    61  	if !u.Valid {
    62  		return nil, nil
    63  	}
    64  	// Delegate to UUID Value function
    65  	return u.UUID.Value()
    66  }
    67  
    68  // Scan implements the sql.Scanner interface.
    69  func (u *NullUUID) Scan(src interface{}) error {
    70  	if src == nil {
    71  		u.UUID, u.Valid = Nil, false
    72  		return nil
    73  	}
    74  
    75  	// Delegate to UUID Scan function
    76  	u.Valid = true
    77  	return u.UUID.Scan(src)
    78  }