migrate

Documentation

Overview

Package migration allows to perform versioned migrations in your ElasticEngine.

Index

• Constants
• func HasVersion(migrations []Migration, version uint) bool
• type Migration
• type MigrationFunc
• type Migrations
  • func (m Migrations) Sort()
• type Migrator
  • func NewMigrator(opts NewMigratorOptions) *Migrator
  • func (m *Migrator) Down(ctx context.Context, targetVersion int) error
  • func (m *Migrator) LatestMigrationVersion() uint
  • func (m *Migrator) SetMigrationsIndex(name string)
  • func (m *Migrator) Up(ctx context.Context, targetVersion int) error
  • func (m *Migrator) Version(ctx context.Context) (migrationVersionInfo, error)
• type NewMigratorOptions

Constants

const AllAvailable = -1

AllAvailable used in "Up" or "Down" methods to run all available migrations.

Functions

func HasVersion

func HasVersion(migrations []Migration, version uint) bool

Types

type Migration

type Migration struct {
	Version     uint
	Description string
	Up          MigrationFunc
	Down        MigrationFunc
}

Migration represents single engine migration. Migration contains:

- version: migration version, must be unique in migration list

- description: text description of migration

- up: callback which will be called in "up" migration process

- down: callback which will be called in "down" migration process for reverting changes

type MigrationFunc

type MigrationFunc func(ctx context.Context, engine elasticx.Engine) error

MigrationFunc is used to define actions to be performed for a migration.

type Migrations

type Migrations []Migration

func (Migrations) Sort

func (m Migrations) Sort()

type Migrator

type Migrator struct {
	// contains filtered or unexported fields
}

Migrate is type for performing migrations in provided database. Database versioned using dedicated collection. Each migration applying ("up" and "down") adds new document to collection. This document consists migration version, migration description and timestamp. Current database version determined as version in latest added document (biggest "_key") from collection mentioned above.

func NewMigrator

func NewMigrator(opts NewMigratorOptions) *Migrator

func (*Migrator) Down

func (m *Migrator) Down(ctx context.Context, targetVersion int) error

Down performs "down" migration to bring back migrations to `version`. If targetVersion<=0 all "down" migrations will be performed. If targetVersion>0, only the down migrations where version>targetVersion will be performed (only if they were applied).

func (*Migrator) LatestMigrationVersion

func (m *Migrator) LatestMigrationVersion() uint

func (*Migrator) SetMigrationsIndex

func (m *Migrator) SetMigrationsIndex(name string)

SetMigrationsIndex replaces name of index for storing migration information. By default it is "migrations".

func (*Migrator) Up

func (m *Migrator) Up(ctx context.Context, targetVersion int) error

Up performs "up" migrations up to the specified targetVersion. If targetVersion<=0 all "up" migrations will be executed (if not executed yet) If targetVersion>0 only migrations where version<=targetVersion will be performed (if not executed yet)

func (*Migrator) Version

func (m *Migrator) Version(ctx context.Context) (migrationVersionInfo, error)

Version returns current engine version and comment.

type NewMigratorOptions

type NewMigratorOptions struct {
	Engine     elasticx.Engine
	Package    string
	Migrations Migrations
}