storj/internal/migrate/create.go
2019-01-24 15:15:10 -05:00

68 lines
1.6 KiB
Go

// Copyright (C) 2019 Storj Labs, Inc.
// See LICENSE for copying information.
package migrate
import (
"database/sql"
"github.com/zeebo/errs"
"storj.io/storj/pkg/utils"
)
// DB is the minimal implementation that is needed by migration.
type DB interface {
Begin() (*sql.Tx, error)
Schema() string
Rebind(string) string
}
// Error is the default migrate errs class
var Error = errs.Class("migrate")
// Create with a previous schema check
func Create(identifier string, db DB) error {
tx, err := db.Begin()
if err != nil {
return Error.Wrap(err)
}
schema := db.Schema()
_, err = tx.Exec(db.Rebind(`CREATE TABLE IF NOT EXISTS table_schemas (id text, schemaText text);`))
if err != nil {
return Error.Wrap(utils.CombineErrors(err, tx.Rollback()))
}
row := tx.QueryRow(db.Rebind(`SELECT schemaText FROM table_schemas WHERE id = ?;`), identifier)
var previousSchema string
err = row.Scan(&previousSchema)
// not created yet
if err == sql.ErrNoRows {
_, err := tx.Exec(schema)
if err != nil {
return Error.Wrap(utils.CombineErrors(err, tx.Rollback()))
}
_, err = tx.Exec(db.Rebind(`INSERT INTO table_schemas(id, schemaText) VALUES (?, ?);`), identifier, schema)
if err != nil {
return Error.Wrap(utils.CombineErrors(err, tx.Rollback()))
}
return Error.Wrap(tx.Commit())
}
if err != nil {
return Error.Wrap(utils.CombineErrors(err, tx.Rollback()))
}
if schema != previousSchema {
err := Error.New("schema mismatch:\nold %v\nnew %v", previousSchema, schema)
return Error.Wrap(utils.CombineErrors(err, tx.Rollback()))
}
return Error.Wrap(tx.Rollback())
}