migrate/source/stub/stub.go

86 lines
2.2 KiB
Go

package stub
import (
"bytes"
"fmt"
"io"
"io/ioutil"
"os"
"github.com/golang-migrate/migrate/v4/source"
)
func init() {
source.Register("stub", &Stub{})
}
type Config struct{}
// d, _ := source.Open("stub://")
// d.(*stub.Stub).Migrations =
type Stub struct {
Url string
Instance interface{}
Migrations *source.Migrations
Config *Config
}
func (s *Stub) Open(url string) (source.Driver, error) {
return &Stub{
Url: url,
Migrations: source.NewMigrations(),
Config: &Config{},
}, nil
}
func WithInstance(instance interface{}, config *Config) (source.Driver, error) {
return &Stub{
Instance: instance,
Migrations: source.NewMigrations(),
Config: config,
}, nil
}
func (s *Stub) Close() error {
return nil
}
func (s *Stub) First() (version uint, err error) {
if v, ok := s.Migrations.First(); !ok {
return 0, &os.PathError{Op: "first", Path: s.Url, Err: os.ErrNotExist} // TODO: s.Url can be empty when called with WithInstance
} else {
return v, nil
}
}
func (s *Stub) Prev(version uint) (prevVersion uint, err error) {
if v, ok := s.Migrations.Prev(version); !ok {
return 0, &os.PathError{Op: fmt.Sprintf("prev for version %v", version), Path: s.Url, Err: os.ErrNotExist}
} else {
return v, nil
}
}
func (s *Stub) Next(version uint) (nextVersion uint, err error) {
if v, ok := s.Migrations.Next(version); !ok {
return 0, &os.PathError{Op: fmt.Sprintf("next for version %v", version), Path: s.Url, Err: os.ErrNotExist}
} else {
return v, nil
}
}
func (s *Stub) ReadUp(version uint) (r io.ReadCloser, identifier string, err error) {
if m, ok := s.Migrations.Up(version); ok {
return ioutil.NopCloser(bytes.NewBufferString(m.Identifier)), fmt.Sprintf("%v.up.stub", version), nil
}
return nil, "", &os.PathError{Op: fmt.Sprintf("read up version %v", version), Path: s.Url, Err: os.ErrNotExist}
}
func (s *Stub) ReadDown(version uint) (r io.ReadCloser, identifier string, err error) {
if m, ok := s.Migrations.Down(version); ok {
return ioutil.NopCloser(bytes.NewBufferString(m.Identifier)), fmt.Sprintf("%v.down.stub", version), nil
}
return nil, "", &os.PathError{Op: fmt.Sprintf("read down version %v", version), Path: s.Url, Err: os.ErrNotExist}
}