// Create creates new migration files on disk
func Create(url, migrationsPath, name string) (*file.MigrationFile, error) {
d, err := driver.New(url)
if err != nil {
return nil, err
}
files, err := file.ReadMigrationFiles(migrationsPath, file.FilenameRegex(d.FilenameExtension()))
if err != nil {
return nil, err
}
version := uint64(0)
if len(files) > 0 {
lastFile := files[len(files)-1]
version = lastFile.Version
}
version += 1
versionStr := strconv.FormatUint(version, 10)
length := 4 // TODO(mattes) check existing files and try to guess length
if len(versionStr)%length != 0 {
versionStr = strings.Repeat("0", length-len(versionStr)%length) + versionStr
}
filenamef := "%s_%s.%s.%s"
name = strings.Replace(name, " ", "_", -1)
mfile := &file.MigrationFile{
Version: version,
UpFile: &file.File{
Path: migrationsPath,
FileName: fmt.Sprintf(filenamef, versionStr, name, "up", d.FilenameExtension()),
Name: name,
Content: []byte(""),
Direction: direction.Up,
},
DownFile: &file.File{
Path: migrationsPath,
FileName: fmt.Sprintf(filenamef, versionStr, name, "down", d.FilenameExtension()),
Name: name,
Content: []byte(""),
Direction: direction.Down,
},
}
if err := ioutil.WriteFile(path.Join(mfile.UpFile.Path, mfile.UpFile.FileName), mfile.UpFile.Content, 0644); err != nil {
return nil, err
}
if err := ioutil.WriteFile(path.Join(mfile.DownFile.Path, mfile.DownFile.FileName), mfile.DownFile.Content, 0644); err != nil {
return nil, err
}
return mfile, nil
}
// initDriverAndReadMigrationFilesAndGetVersion is a small helper
// function that is common to most of the migration funcs
func initDriverAndReadMigrationFilesAndGetVersion(url, migrationsPath string) (driver.Driver, *file.MigrationFiles, uint64, error) {
d, err := driver.New(url)
if err != nil {
return nil, nil, 0, err
}
files, err := file.ReadMigrationFiles(migrationsPath, file.FilenameRegex(d.FilenameExtension()))
if err != nil {
d.Close() // TODO what happens with errors from this func?
return nil, nil, 0, err
}
version, err := d.Version()
if err != nil {
d.Close() // TODO what happens with errors from this func?
return nil, nil, 0, err
}
return d, &files, version, nil
}