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diff --git a/vendor/github.com/rubenv/sql-migrate/README.md b/vendor/github.com/rubenv/sql-migrate/README.md new file mode 100644 index 0000000..9ac432e --- /dev/null +++ b/vendor/github.com/rubenv/sql-migrate/README.md @@ -0,0 +1,289 @@ +# sql-migrate + +> SQL Schema migration tool for [Go](http://golang.org/). Based on [gorp](https://github.com/go-gorp/gorp) and [goose](https://bitbucket.org/liamstask/goose). + +[](https://travis-ci.org/rubenv/sql-migrate) [](https://godoc.org/github.com/rubenv/sql-migrate) + +Using [modl](https://github.com/jmoiron/modl)? Check out [modl-migrate](https://github.com/rubenv/modl-migrate). + +## Features + +* Usable as a CLI tool or as a library +* Supports SQLite, PostgreSQL, MySQL, MSSQL and Oracle databases (through [gorp](https://github.com/go-gorp/gorp)) +* Can embed migrations into your application +* Migrations are defined with SQL for full flexibility +* Atomic migrations +* Up/down migrations to allow rollback +* Supports multiple database types in one project + +## Installation + +To install the library and command line program, use the following: + +```bash +go get -v github.com/rubenv/sql-migrate/... +``` + +## Usage + +### As a standalone tool + +``` +$ sql-migrate --help +usage: sql-migrate [--version] [--help] <command> [<args>] + +Available commands are: + down Undo a database migration + new Create a new migration + redo Reapply the last migration + status Show migration status + up Migrates the database to the most recent version available +``` + +Each command requires a configuration file (which defaults to `dbconfig.yml`, but can be specified with the `-config` flag). This config file should specify one or more environments: + +```yml +development: + dialect: sqlite3 + datasource: test.db + dir: migrations/sqlite3 + +production: + dialect: postgres + datasource: dbname=myapp sslmode=disable + dir: migrations/postgres + table: migrations +``` + +The `table` setting is optional and will default to `gorp_migrations`. + +The environment that will be used can be specified with the `-env` flag (defaults to `development`). + +Use the `--help` flag in combination with any of the commands to get an overview of its usage: + +``` +$ sql-migrate up --help +Usage: sql-migrate up [options] ... + + Migrates the database to the most recent version available. + +Options: + + -config=config.yml Configuration file to use. + -env="development" Environment. + -limit=0 Limit the number of migrations (0 = unlimited). + -dryrun Don't apply migrations, just print them. +``` + +The `new` command creates a new empty migration template using the following pattern `<current time>-<name>.sql`. + +The `up` command applies all available migrations. By contrast, `down` will only apply one migration by default. This behavior can be changed for both by using the `-limit` parameter. + +The `redo` command will unapply the last migration and reapply it. This is useful during development, when you're writing migrations. + +Use the `status` command to see the state of the applied migrations: + +```bash +$ sql-migrate status ++---------------+-----------------------------------------+ +| MIGRATION | APPLIED | ++---------------+-----------------------------------------+ +| 1_initial.sql | 2014-09-13 08:19:06.788354925 +0000 UTC | +| 2_record.sql | no | ++---------------+-----------------------------------------+ +``` + +### MySQL Caveat + +If you are using MySQL, you must append `?parseTime=true` to the `datasource` configuration. For example: + +```yml +production: + dialect: mysql + datasource: root@/dbname?parseTime=true + dir: migrations/mysql + table: migrations +``` + +See [here](https://github.com/go-sql-driver/mysql#parsetime) for more information. + +### As a library + +Import sql-migrate into your application: + +```go +import "github.com/rubenv/sql-migrate" +``` + +Set up a source of migrations, this can be from memory, from a set of files or from bindata (more on that later): + +```go +// Hardcoded strings in memory: +migrations := &migrate.MemoryMigrationSource{ + Migrations: []*migrate.Migration{ + &migrate.Migration{ + Id: "123", + Up: []string{"CREATE TABLE people (id int)"}, + Down: []string{"DROP TABLE people"}, + }, + }, +} + +// OR: Read migrations from a folder: +migrations := &migrate.FileMigrationSource{ + Dir: "db/migrations", +} + +// OR: Use migrations from a packr box +migrations := &migrate.PackrMigrationSource{ + Box: packr.NewBox("./migrations"), +} + +// OR: Use migrations from bindata: +migrations := &migrate.AssetMigrationSource{ + Asset: Asset, + AssetDir: AssetDir, + Dir: "migrations", +} +``` + +Then use the `Exec` function to upgrade your database: + +```go +db, err := sql.Open("sqlite3", filename) +if err != nil { + // Handle errors! +} + +n, err := migrate.Exec(db, "sqlite3", migrations, migrate.Up) +if err != nil { + // Handle errors! +} +fmt.Printf("Applied %d migrations!\n", n) +``` + +Note that `n` can be greater than `0` even if there is an error: any migration that succeeded will remain applied even if a later one fails. + +Check [the GoDoc reference](https://godoc.org/github.com/rubenv/sql-migrate) for the full documentation. + +## Writing migrations +Migrations are defined in SQL files, which contain a set of SQL statements. Special comments are used to distinguish up and down migrations. + +```sql +-- +migrate Up +-- SQL in section 'Up' is executed when this migration is applied +CREATE TABLE people (id int); + + +-- +migrate Down +-- SQL section 'Down' is executed when this migration is rolled back +DROP TABLE people; +``` + +You can put multiple statements in each block, as long as you end them with a semicolon (`;`). + +You can alternatively set up a separator string that matches an entire line by setting `sqlparse.LineSeparator`. This +can be used to imitate, for example, MS SQL Query Analyzer functionality where commands can be separated by a line with +contents of `GO`. If `sqlparse.LineSeparator` is matched, it will not be included in the resulting migration scripts. + +If you have complex statements which contain semicolons, use `StatementBegin` and `StatementEnd` to indicate boundaries: + +```sql +-- +migrate Up +CREATE TABLE people (id int); + +-- +migrate StatementBegin +CREATE OR REPLACE FUNCTION do_something() +returns void AS $$ +DECLARE + create_query text; +BEGIN + -- Do something here +END; +$$ +language plpgsql; +-- +migrate StatementEnd + +-- +migrate Down +DROP FUNCTION do_something(); +DROP TABLE people; +``` + +The order in which migrations are applied is defined through the filename: sql-migrate will sort migrations based on their name. It's recommended to use an increasing version number or a timestamp as the first part of the filename. + +Normally each migration is run within a transaction in order to guarantee that it is fully atomic. However some SQL commands (for example creating an index concurrently in PostgreSQL) cannot be executed inside a transaction. In order to execute such a command in a migration, the migration can be run using the `notransaction` option: + +```sql +-- +migrate Up notransaction +CREATE UNIQUE INDEX people_unique_id_idx CONCURRENTLY ON people (id); + +-- +migrate Down +DROP INDEX people_unique_id_idx; +``` + +## Embedding migrations with [packr](https://github.com/gobuffalo/packr) + +If you like your Go applications self-contained (that is: a single binary): use [packr](https://github.com/gobuffalo/packr) to embed the migration files. + +Just write your migration files as usual, as a set of SQL files in a folder. + +Use the `PackrMigrationSource` in your application to find the migrations: + +```go +migrations := &migrate.PackrMigrationSource{ + Box: packr.NewBox("./migrations"), +} +``` + +If you already have a box and would like to use a subdirectory: + +```go +migrations := &migrate.PackrMigrationSource{ + Box: myBox, + Dir: "./migrations", +} +``` + +## Embedding migrations with [bindata](https://github.com/shuLhan/go-bindata) + +As an alternative, but slightly less maintained, you can use [bindata](https://github.com/shuLhan/go-bindata) to embed the migration files. + +Just write your migration files as usual, as a set of SQL files in a folder. + +Then use bindata to generate a `.go` file with the migrations embedded: + +```bash +go-bindata -pkg myapp -o bindata.go db/migrations/ +``` + +The resulting `bindata.go` file will contain your migrations. Remember to regenerate your `bindata.go` file whenever you add/modify a migration (`go generate` will help here, once it arrives). + +Use the `AssetMigrationSource` in your application to find the migrations: + +```go +migrations := &migrate.AssetMigrationSource{ + Asset: Asset, + AssetDir: AssetDir, + Dir: "db/migrations", +} +``` + +Both `Asset` and `AssetDir` are functions provided by bindata. + +Then proceed as usual. + +## Extending + +Adding a new migration source means implementing `MigrationSource`. + +```go +type MigrationSource interface { + FindMigrations() ([]*Migration, error) +} +``` + +The resulting slice of migrations will be executed in the given order, so it should usually be sorted by the `Id` field. + +## License + +This library is distributed under the [MIT](LICENSE) license. |