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migrate

Database migrations written in Go. Use as CLI or import as library.

Migrate reads migrations from sources and applies them in correct order to a database.
Drivers are "dumb", migrate glues everything together and makes sure the logic is bulletproof. (Keeps the drivers lightweight, too.)
Database drivers don't assume things or try to correct user input. When in doubt, fail.

Databases

Database drivers run migrations. Add a new database?

Database URLs

Database connection strings are specified via URLs. The URL format is driver dependent but generally has the form: dbdriver://username:password@host:port/dbname?option1=true&option2=false

Any reserved URL characters need to be escaped. Note, the % character also needs to be escaped

Explicitly, the following characters need to be escaped: !, #, $, %, &, ', (, ), *, +, ,, /, :, ;, =, ?, @, [, ]

It's easiest to always run the URL parts of your DB connection URL (e.g. username, password, etc) through an URL encoder. See the example Python snippets below:

$ python3 -c 'import urllib.parse; print(urllib.parse.quote(input("String to encode: "), ""))'
String to encode: FAKEpassword!#$%&'()*+,/:;=?@[]
FAKEpassword%21%23%24%25%26%27%28%29%2A%2B%2C%2F%3A%3B%3D%3F%40%5B%5D
$ python2 -c 'import urllib; print urllib.quote(raw_input("String to encode: "), "")'
String to encode: FAKEpassword!#$%&'()*+,/:;=?@[]
FAKEpassword%21%23%24%25%26%27%28%29%2A%2B%2C%2F%3A%3B%3D%3F%40%5B%5D
$

Migration Sources

Source drivers read migrations from local or remote sources. Add a new source?

Filesystem - read from fileystem
Go-Bindata - read from embedded binary data (jteeuwen/go-bindata)
Github - read from remote Github repositories
Gitlab - read from remote Gitlab repositories
AWS S3 - read from Amazon Web Services S3
Google Cloud Storage - read from Google Cloud Platform Storage

CLI usage

Simple wrapper around this library.
Handles ctrl+c (SIGINT) gracefully.
No config search paths, no config files, no magic ENV var injections.

CLI Documentation

Basic usage:

$ migrate -source file://path/to/migrations -database postgres://localhost:5432/database up 2

Docker usage

$ docker run -v {{ migration dir }}:/migrations --network host migrate/migrate
    -path=/migrations/ -database postgres://localhost:5432/database up 2

Use in your Go project

API is stable and frozen for this release (v3 & v4).
Uses Go modules to manage dependencies.
To help prevent database corruptions, it supports graceful stops via GracefulStop chan bool.
Bring your own logger.
Uses io.Reader streams internally for low memory overhead.
Thread-safe and no goroutine leaks.

Go Documentation

import (
    "github.com/golang-migrate/migrate/v4"
    _ "github.com/golang-migrate/migrate/v4/database/postgres"
    _ "github.com/golang-migrate/migrate/v4/source/github"
)

func main() {
    m, err := migrate.New(
        "github://mattes:personal-access-token@mattes/migrate_test",
        "postgres://localhost:5432/database?sslmode=enable")
    m.Steps(2)
}

Want to use an existing database client?

import (
    "database/sql"
    _ "github.com/lib/pq"
    "github.com/golang-migrate/migrate/v4"
    "github.com/golang-migrate/migrate/v4/database/postgres"
    _ "github.com/golang-migrate/migrate/v4/source/file"
)

func main() {
    db, err := sql.Open("postgres", "postgres://localhost:5432/database?sslmode=enable")
    driver, err := postgres.WithInstance(db, &postgres.Config{})
    m, err := migrate.NewWithDatabaseInstance(
        "file:///migrations",
        "postgres", driver)
    m.Steps(2)
}

Migration files

Each migration has an up and down migration. Why?

1481574547_create_users_table.up.sql
1481574547_create_users_table.down.sql

Best practices: How to write migrations.

Versions

Version	Supported?	Import	Notes
master	✅	`import "github.com/golang-migrate/migrate/v4"`	New features and bug fixes arrive here first
v4	✅	`import "github.com/golang-migrate/migrate/v4"`	Used for stable releases
v3	❌	`import "github.com/golang-migrate/migrate"` (with package manager) or `import "gopkg.in/golang-migrate/migrate.v3"` (not recommended)	DO NOT USE - No longer supported

Development and Contributing

Yes, please! Makefile is your friend, read the development guide.

Also have a look at the FAQ.

Looking for alternatives? https://awesome-go.com/#database.

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