README.md

migerl

Yet another database migration tool written in Erlang.

What it does

• Manages applied/unapplied migrations
• Runs a migration with multiple queries under a transaction whenever possible

Database Coverage

• MySQL
• PostgreSQL

How to install

1. With Erlang/OTP runtime, download release binary from releases.
2. Without Erlang/OTP runtime, pull docker image with docker pull yowcow/migerl.

How to use

Usage: migerl [-c <config>] [-e [<env>]] [-d [<dir>]] [-t [<title>]]
              [-a [<all>]] [-v [<version>]] [-h [<help>]] [command ...]

  -c, --config   Config file
  -e, --env      Env name in config [default: default]
  -d, --dir      Migration script directory [default: scripts]
  -t, --title    Migration title [default: untitled]
  -a, --all      Apply/Unapply all [default: false]
  -v, --version  Print version [default: false]
  -h, --help     Print this help [default: false]
  command        Commands to execute (e.g. init, new, status, up, down)

Initialize:

migerl -c path/to/config init

Create a new migration file:

migerl -c path/to/config -t the_new_migration new

Show current status:

migerl -c path/to/config status

Apply 1 migration:

migerl -c path/to/config up

Undo 1 migration:

migerl -c path/to/config down

Apply all unapplied migrations:

migerl -c path/to/config -a up

Undo all applied migrations:

migerl -c path/to/config -a down

Configuration file

Should be in erlang proplist:

[
  {"default", [
    {dialect, mysql},
    {config, [
      {host, "127.0.0.1"},
      {port, 3306},
      {user, "test-migration-user"},
      {password, "test-user-p@ssw0rd"},
      {database, "test_db"},
      {queries, [
        "SET NAMES utf8mb4"
      ]}
    ]}
  ]},
  {"devel", [
    {dialect, mysql},
    {config, [
      {host, "devel-db-host"},
      {port, 3306},
      {user, "devel-migration-user"},
      {password, "devel-user-p@ssw0rd"},
      {database, "devel_db"},
      {queries, [
        "SET NAMES utf8mb4"
      ]}
    ]}
  ]},
  {"prod", [
    {dialect, mysql},
    {config, [
      {host, "prod-db-host"},
      {port, 3306},
      {user, "prod-migration-user"},
      {password, "devel-user-p@ssw0rd"},
      {database, "prod_db"},
      {queries, [
        "SET NAMES utf8mb4"
      ]}
    ]}
  ]},
  {"postgresql", [
    {dialect, postgres},
    {config, #{
      host => "localhost",
      username => "postgres",
      password => "",
      database => "migerl_test",
      port => 5432
    }}
  ]}
].

Build

rebar3 escriptize

See Makefile, docker.mk for development.