okveast
east - node.js database migration tool for different databases (extensible via adapters) with transpiled languages support (e.g. TypeScript).
east connects to the db using particular adapter (mongodb, sqlite, postgres,
mysql, couchbase, couchdb), keeps track of executed migrations by storing their names
inside db and makes connect to the db available inside migrate and rollback
functions. east encourages you to use for migrations driver/syntax with which
you are already familiar with (apparently you use it for work with db at your
application) and doesn't provide universal api for working with any kind of
database.
Following subjects described below:
- Node.js compatibility
- Installation
- Changelog
- Cli usage
- Library usage
- Adapters
- Plugins
- Creating own adapter
- TypeScript and other transpiled languages support
- ECMAScript Modules support
- License
Node.js compatibility
east itself requires node.js >= 10.17.0 to work.
Please note that particular adapter may have other requirements (see documentation for specific adapter).
Installation
npm install east -galternatively you could install it locally
Changelog
All notable changes to this project documented in CHANGELOG.md.
Cli usage
At your project dir run
east initafter that you can create, migrate, rollback your migrations.
Run east -h to see all commands:
Usage: east [options] [command]
Options:
-V, --version output the version number
--adapter <name> which db adapter to use
--config <path> config file to use
--timeout <timeout> timeout for migrate/rollback
--template <path> path to template for new migrations
--dir <dir> dir where migration executable files are stored (default: "./migrations")
--source-dir <dir> dir where migration source files are stored, equal to --dir by default
--migration-extension <ext> migration executable files extension name (default: "js")
--source-migration-extension <ext> migration source files extension name, equal to --migration-extension by default
--url <url> db connect url
--trace verbose mode (includes error stack trace)
--silent prevent output of detailed log
--es-modules config, migrations, adapter and plugins could be provided as ES Modules with this flag
--no-exit require a clean shutdown of the event loop: process.exit will not be called at the end
-h, --help display help for command
Commands:
init initialize migration system
create <basename> create new migration based on template
migrate [options] [migrations...] run all or selected migrations
rollback [options] [migrations...] rollback all or selected migrations
list [options] [status] list migration with selected status ("new", "executed" or "all"), "new" by default
*
help [command] display help for commandrun east <command> -h to see detailed command help.
All options described above can be set via command line or at .eastrc file
located at current directory, e.g.:
{
"dir": "./dbmigration",
"template": "./lib/node/utils/customMigrationTemplate.js"
}.eastrc also can be a regular commonjs module (instead of json file):
var path = require('path');
module.exports = {
dir: path.join(__dirname, 'dbmigration'),
template: './lib/node/utils/customMigrationTemplate.js'
};east also supports config as ECMAScript module, config could be:
import path from 'path';
export const dir = path.resolve('dbmigration');
export const template = path.resolve('./lib/node/utils/customMigrationTemplate.js');
`See ECMAScript Modules support for details.
create
east create doSomethingproduces something like this
New migration "1_doSomething" created at "migrations/1_doSomething.js"the created file will contain
exports.tags = [];
exports.migrate = async (client) => {
};
exports.rollback = async (client) => {
};clientrepresents a connection to the current db and it's determined by the adapter (see adapters section)donecallback may be defined as second argument - should be called at the end of the migration (if any error occures you can pass it as the first argument)rollbackfunction is optional and may be omitted
Migration file is a regular node.js module and allows migrating any database e.g.
// include your database wrapper which you already use in app
const db = require('./db');
exports.migrate = async (client) => {
await db.connect();
await db.things.insert({_id: 1, name: 'apple', color: 'red'});
};
exports.rollback = async (client) => {
await db.connect();
await db.things.remove({_id: 1});
};or you can use a special adapter for database (see adapters section).
Migration file number format
The default format for migration file names is to prepend a number to the filename which is incremented with every new file. This creates migration files such as "migrations/1_doSomething.js", "migrations/2_doSomethingElse.js".
If you prefer your files to be created with a date-time instead of sequential
numbers, you can set the migrationNumberFormat configuration parameter in
your .eastrc to "dateTime":
{
"migrationNumberFormat": "dateTime"
}This will create migration files with date-time prefix in YYYYMMDDhhmmss
format (e.g. "migrations/20190720172730_doSomething.js").
For the default behavior, you can omit the migrationNumberFormat
configuration option or set it to:
{
"migrationNumberFormat": "sequentialNumber"
}migrate
let's create one more migration
east create doSomethingElsethen executes both of them
east migrateit sequentially executes all new migrations and produces
target migrations:
1_doSomething
2_doSomethingElse
migrate "1_doSomething"
migration done
migrate "2_doSomethingElse"
migration doneselected migrations can be executed by passing their names (or numbers or basenames or paths) as an argument
east migrate 1_doSomething 2in our case this command will skip all of them
skip "1_doSomething" because it's already executed
skip "2_doSomethingElse" because it's already executed
nothing to migrateyou can pass --force option to execute already executed migrations.
This is useful while you develop and test your migration.
You also can export tags array from migration and then run only
migrations that satisfy the expression specified by --tag option. The expression
consists of tag names and boolean operators &, | and !. For example,
the following command will run all migrations that have "tag1" tag and do not have "tag2" tag:
east migrate --tag 'tag1 & !tag2'rollback
rollback has similar to migrate command syntax but executes rollback
function from the migration file
east rollbackwill produce
target migrations:
2_doSomethingElse
1_doSomething
rollback "2_doSomethingElse"
migration successfully rolled back
rollback "1_doSomething"
migration successfully rolled backlist
east listshows new migrations e.g.
new migrations:
1_doSomething
2_doSomethingElsetarget status could be specified as an argument e.g.
east list executedLibrary usage
east exposes MigrationManager class (descendant of EventEmitter) which for
example can be used to migrate your database from node.js app without using
east cli:
const {MigrationManager} = require('east');
const main = async () => {
const migrationManager = new MigrationManager();
// log target migrations before execution
migrationManager.once('beforeMigrateMany', (migrationNames) => {
console.log('Target migrations: ', migrationNames);
});
await migrationManager.configure();
try {
await migrationManager.connect();
// select for migration all not executed migrations
await migrationManager.migrate({status: 'new'});
}
finally {
await migrationManager.disconnect();
}
}
main().catch((err) => {
console.error('Some error occurred: ', err.stack || err);
});
`MigrationManager methods:
configure(params) - configures migration process, accepts object with parameters (
dir,adapter, etc) and merges it with loaded config (whenloadConfigparam is truthy - true by default). Returns Promise<void>. This method should be called before any other methods.getParams() - returns Promise with parameters used by migration process after configuration(
configuremethod).init() - initiates migration process for a project. Should be called once per project. Returns Promise<void>.
isInitialized() - checks whether
initwas made or not. Returns Promise<Boolean>.create(basename) - creates migration, returns Promise with migration object.
getMigrationPath(name, migrationFileType) - returns an absolute path of the migration file on disk by the name of the migration,
migrationFileTypecan be one of "executable" or "source" ("executable" by default). Returns Promise<String>.connect() - connects to database management system (if supposed by adapter). Returns Promise<void>.
getMigrationNames({migrations, status, tag, reverseOrderResult}) - returns migrations names, following options are provided:
- migrations - array of target migrations, each migration could be defined by basename, full name, path or number.
- status - status to filter migrations, supported statuses are: "new", "executed" and "all".
- tag - tag expression to filter migrations e.g. "tag1 & !tag2"
- reverseOrderResult - if true then result array will be reversed.
migrations and status are mutually exclusive.
If migrations, status not provided then all migrations will be processed
(e.g. filtered by tag and returned).
migrate({migrations, status, tag, force}) - executes target migrations. Target migration could be defined by
migrations,status,tagoptions (see it's description atgetMigrationNamesmethod). By default migrations with status "new" are chosen. Returns Promise<void>.forceflag allows to execute already executed migrations.rollback({migrations, status, tag, force}) - rollbacks target migrations. Target migration could be defined by
migrations,status,tagoptions (see it's description atgetMigrationNamesmethod). By default migrations with status "executed" are chosen. Returns Promise<void>.forceflag allows to rollback not executed migrations.disconnect() - disconnects from database management system (if supposed by adapter). Returns Promise<void>.
MigrationManager events:
- beforeMigrateOne({migration})
- afterMigrateOne({migration})
- beforeMigrateMany({migrationNames})
- afterMigrateMany({migrationNames})
- beforeRollbackOne({migration})
- afterRollbackOne({migration})
- beforeRollbackMany({migrationNames})
- afterRollbackMany({migrationNames})
- onSkipMigration({migration, reason})
Adapters
adapter determines where executed migration names will be stored and what will be
passed to migrate and rollback function as client.
Default adapter stores executed migration names at file .migrations which is
located at migrations executables directory and passes null as client.
Other adapters:
Plugins
East functionality could be extended by using plugins, for usage instructions see plugin page:
Creating own adapter
For writing your own adapter you should implement methods for connection, mark transaction as executed, etc see details inside built-in adapter and other adapters. See TypeScript support for the details on the required adapter interface.
You also can run migrator tests from current repository against your adapter:
- Clone current repository
- Change current directory to it
- Create file
.eastrcwith path and parameters for your adapter e.g.
{
"adapter": "../../east-mysql/lib/adapter",
"url": "mysql://user:password@localhost/east_test_db",
"createDbOnConnect": true
}- Run
NODE_EAST_TEST_LOAD_CONFIG=1 npm run testSpecified test/01-migrator -- --jobs=1at root of the cloned repository.
TypeScript and other transpiled languages support
east allows you to opt-in writing and executing your migrations with any transpiled languages,
while by default it uses a single dir called "migrations" and looks for ".js" files in it.
You can configure separate executable and source files directories as well as
separate executable and source files extensions with --dir, --source-dir,
--migration-extension, --source-migration-extension respectively.
By default if you specify only --dir and/or --migration-extension, then
--source-dir and/or --source-migration-extension will be equal to it, however
it doesn't work on the other way around, e.g. if you specify
--source-dir mySourceDir --source-migration-extension tsthen --dir and --migration-extension will have migrations and js values by default,
so it is recommended to specify at least --dir, --source-dir and --source-migration-extension
when you are building a transpiled language.
If you use TypeScript you can run east with ts-node
if you don't want to transpile you migration scripts before running them:
ts-node $(which east) migrateJust be sure to specify --migration-extension ts so that east does look for
TypeScript files when require()-ing the migration scripts.
TypeScript typings
east exposes TypeScript declarations of the Adapter, MigrationManager
and other related interfaces.
You can access it by importing the interfaces from east module itself:
import { DbClient } from 'some-mainstream-db';
import type { Adapter, AdapterConstructor } from 'east';
class MyAdapter implements Adapter<DbClient> {
// go to definition of Adapter interface for documentation on required methods
// you can also leverage your ide features to generate
// stub method impementations here
}
// type-check the class static type (i.e. its constructor)
const _: AdpaterConstructor<DbClient> = MyAdapter;
export = MyAdapter;ECMAScript Modules support
east provides support for es modules by --es-modules cli flag.
With this flag config, migrations, adapter and plugins will be loaded using
import expression.
It allows to provide those entities like commonjs or es modules, e.g.
.eastrc.mjs:
import path from 'path';
export const dir = path.resolve('dbmigration');
export const template = path.resolve('./lib/node/utils/customMigrationTemplate.js');
`Please note, that you need to enable nodejs es modules support (use mjs
extension for module or package.json with type "module", etc - see
nodejs esm docs for
details).
Config presented above could be used like this:
east --config .eastrc.mjs --es-modules listWhen migration files as es module are desired --migration-extension and
--source-migration-extension set to "mjs" could be used.
License
MIT