erikgreasy/wp-db-migrations

WordPress database migrations

WordPress database migrations

Databse migrations for WordPress inspired by Laravel framework.

Installation

There are few ways you can install WP DB migrations:

1. Install as a mu-plugin.

Download the latest release ZIP and extract it into your mu-plugins. You will need some type of must-use plugins autoloader in order for this to work, for example Bedrock Autoloader.

2. Install as a regular plugin

Download the latest release ZIP and extract it into your plugins, or install via wp-admin plugins section.

Getting started

Registering your migrations folders

When running the migrations with WP CLI command, the plugin scans all folders that are registered as "migrations folders". Migration folder is basically a folder in your plugin/theme, where your migrations are stored.

The plugin supports registering multiple migrations folders, so you can have separate migration folder for mulitple plugins.

To register a new migration folder, use the following WP filter:

add_filter('dbmigrator_migrations_dirs', function($migrationDirs) {
    $migrationDirs[] = __DIR__ . '/my_plugin_migrations';

    return $migrationDirs;
});

Creating your first migration file

Migration file is just a PHP file, which follows specific structure, so the plugin can scan this file and run.

Migration structure

Simple example migration may look like this:

<?php
// 001_reviewplugin_create_test_table.php

use DbMigrator\Migration;

return new class extends Migration
{
    public function up()
    {
        $tableName = $this->getPrefixedTable('test');
        $charset_collate = $this->wpdb->get_charset_collate();

        $sql = "CREATE TABLE $tableName (
            id int(11) NOT NULL auto_increment,
            name varchar(60) NOT NULL,
            UNIQUE KEY id (id)
        ) $charset_collate;";

        $this->wpdb->query($sql);
    }
};

Few important points to take from example above are:

• we use PHP anonymous classes that extends the base Migration class. This base class provides few useful methods and properties for working with wpdb.
• the up() method is required and contains all your migration logic
• naming convention for the migration file is as follows:
  • to prefix your migration with index (eg. 001)
  • use some kind of identifier (eg. reviewplugin)
  • the rest of the file name should describe what the migration does
  • use snake_case for better readability

Creating migration files

You can create the migrations files manually, or you can generate them with WP CLI command:

wp migrator make:migration 001_your_migration_name

which will create an empty migration with specified name in the location, from where the command was run.

Running your migrations

Now you are ready to run your migrations. To run the migrations, use the WP CLI command:

wp migrator migrate

Add this command to the deploy script of your app, or run the command manually.

Alternatively, you can run the migrations directly, without using WP_CLI, by calling Migrator method. For example, this can be done during the plugin activation:

register_activation_hook(__FILE__, function() {
    (new \DbMigrator\Migrator())->migrate();
});