migrate

Documentation

Index

• Variables
• func Create(ctx context.Context, identifier string, db DBX) error
• func CreateSpanner(ctx context.Context, identifier string, db DBX, forEmulator bool) error
• type Action
• type CreateDB
• type DBX
• type Func
  • func (fn Func) Run(ctx context.Context, log *zap.Logger, db tagsql.DB, tx tagsql.Tx) error
• type Migration
  • func (migration *Migration) CurrentVersion(ctx context.Context, log *zap.Logger, db tagsql.DB) (int, error)
  • func (migration *Migration) Run(ctx context.Context, log *zap.Logger) error
  • func (migration *Migration) TargetVersion(version int) *Migration
  • func (migration *Migration) ValidTableName() error
  • func (migration *Migration) ValidateSteps() error
  • func (migration *Migration) ValidateVersions(ctx context.Context, log *zap.Logger) error
• type SQL
  • func (sql SQL) Run(ctx context.Context, log *zap.Logger, db tagsql.DB, tx tagsql.Tx) (err error)
• type Step

Variables

var (
	// ErrValidateVersionQuery is when there is an error querying version table.
	ErrValidateVersionQuery = errs.Class("validate db version query")
	// ErrValidateVersionMismatch is when the migration version does not match the current database version.
	ErrValidateVersionMismatch = errs.Class("validate db version mismatch")
	// ErrValidateMinVersion is when the migration version does not match the current database version.
	ErrValidateMinVersion = errs.Class("validate minimum version")
)

var Error = errs.Class("migrate")

Error is the default migrate errs class.

Functions

func Create

func Create(ctx context.Context, identifier string, db DBX) error

Create with a previous schema check.

func CreateSpanner

func CreateSpanner(ctx context.Context, identifier string, db DBX, forEmulator bool) error

CreateSpanner creates the migration schema necessary to execute migrations in Spanner.

Types

type Action

type Action interface {
	Run(ctx context.Context, log *zap.Logger, db tagsql.DB, tx tagsql.Tx) error
}

Action is something that needs to be done.

type CreateDB

type CreateDB func(ctx context.Context, log *zap.Logger) error

CreateDB is operation for creating new dbs.

type DBX

type DBX interface {
	tagsql.DB
	Schema() []string
	Rebind(string) string
}

DBX contains additional methods for migrations.

type Func

type Func func(ctx context.Context, log *zap.Logger, db tagsql.DB, tx tagsql.Tx) error

Func is an arbitrary operation.

func (Func) Run

func (fn Func) Run(ctx context.Context, log *zap.Logger, db tagsql.DB, tx tagsql.Tx) error

Run runs the migration.

type Migration

type Migration struct {
	// Table is the table name to register the applied migration version.
	// NOTE: Always validates its value with the ValidTableName method before it's
	// concatenated in a query string for avoiding SQL injection attacks.
	Table string
	Steps []*Step
}

Migration describes a migration steps.

func (*Migration) CurrentVersion

func (migration *Migration) CurrentVersion(ctx context.Context, log *zap.Logger, db tagsql.DB) (int, error)

CurrentVersion finds the latest version for the db.

func (*Migration) Run

func (migration *Migration) Run(ctx context.Context, log *zap.Logger) error

Run runs the migration steps.

func (*Migration) TargetVersion

func (migration *Migration) TargetVersion(version int) *Migration

TargetVersion returns migration with steps upto specified version.

func (*Migration) ValidTableName

func (migration *Migration) ValidTableName() error

ValidTableName checks whether the specified table name is only formed by at least one character and its only formed by lowercase letters and underscores.

NOTE: if you change this function to accept a wider range of characters, make sure that they cannot open to SQL injections because Table field is used concatenated in some queries performed by Mitration methods.

func (*Migration) ValidateSteps

func (migration *Migration) ValidateSteps() error

ValidateSteps checks that the version for each migration step increments in order.

func (*Migration) ValidateVersions

func (migration *Migration) ValidateVersions(ctx context.Context, log *zap.Logger) error

ValidateVersions checks that the version of the migration matches the state of the database.

type SQL

type SQL []string

SQL statements that are executed on the database.

func (SQL) Run

func (sql SQL) Run(ctx context.Context, log *zap.Logger, db tagsql.DB, tx tagsql.Tx) (err error)

Run runs the SQL statements.

type Step

type Step struct {
	DB          *tagsql.DB // The DB to execute this step on
	Description string
	Version     int // Versions should start at 0
	Action      Action
	CreateDB    CreateDB

	// SeparateTx marks a step as it should not be merged together for optimization.
	// Cockroach cannot add a column and update the value in the same transaction.
	SeparateTx bool
}

Step describes a single step in migration.