good-migrations

Good Migrations

A plain and simple migraton library for migrating anything you want.

You could write sql migrations, manipulate files, anything that javascript can do.

Version information is just a single number, and can be stored anywhere you like; in a database, filesystem, in the cloud, anywhere you have access to.

const fs = require('fs');
const migrate = require('good-migrations');

migrate(
	// You need to specify how to read and write version data
	{
		async getVersion(){ return fs.readFileSync('./version', 'utf8'); },
		async setVersion(v){ fs.writeFileSync('./version', v); }
	},
	// Then give a list of migration functions to run
	[
		() => initiateWidgetManager(),
		async () => {
			const p = await calculateConfigurationParameter();
			await modifyConfigurationSetting(p);
		}
	]
).then(()=> console.log('done!'));

SQL Migrations

Because it's such a common use case, an sql-specific migration system is also provided. It creates a table called good_migrations for recording migration status. This table name is not configurable, since there's no standard way to specify a variable as a table name in most sql clients.

It requires you to provide a function for executing SQL queries, which takes the signature of a template tagging function, so you'll probably want to use a library like sql-template-tag if your database client of choice doesn't provide template tags by default. The function should return a promise resolving to an array of result records (if there are any).

The second argument is a key to identify this set of migrations. It allows you to use good-migrations for multiple independent parts of your project.

Finally, the migration functions. You can also provide strings instead of functions and these will be interpreted as sql statements to be executed.

const sql = require('sql-template-tag').default;
const migrate = require('good-migrations').sql;

const query = (literals, ...variables) => myDatabase.queryAll(sql(literals, ...variables));

migrate(
	query,
	'recipes table',
	[
		`CREATE TABLE recipes (title TEXT, body TEXT)`,
		()=>importRecipesFromFile()
	]
).then(()=>console.log('done!'))