askelephant / fireway-esm

A schema migration tool for Firestore updated for Typescript & ESM

fireway

A schema migration tool for firestore heavily inspired by flyway

Install

yarn global add fireway

# or 

npx fireway

Credentials

In order to fireway be able to connect to firestore you need to set up the environment variable GOOGLE_APPLICATION_CREDENTIALS with service account file path.

Example:

export GOOGLE_APPLICATION_CREDENTIALS="path/to/firestore-service-account.json"

CLI

Usage
  $ fireway <command> [options]

Available Commands
  migrate    Migrates schema to the latest version

For more info, run any command with the `--help` flag
  $ fireway migrate --help

Options
  --require        Requires a module before executing
  -v, --version    Displays current version
  -h, --help       Displays this message

Examples
  $ fireway migrate
  $ fireway --require="ts-node/register" migrate

fireway migrate

Description
  Migrates schema to the latest version

Usage
  $ fireway migrate [options]

Options
  --path         Path to migration files  (default ./migrations)
  --projectId    Target firebase project
  --dryrun       Simulates changes
  --forceWait    Forces waiting for migrations that do not strictly manage async calls
  --require      Requires a module before executing
  -h, --help     Displays this message

Examples
  $ fireway migrate
  $ fireway migrate --path=./my-migrations
  $ fireway migrate --projectId=my-staging-id
  $ fireway migrate --dryrun
  $ fireway migrate --forceWait
  $ fireway --require="ts-node/register" migrate

Migration file format

Migration file name format: v[semver]__[description].js

// each script gets a pre-configured firestore admin instance
// possible params: app, firestore, FieldValue, FieldPath, Timestamp, dryrun
module.exports.migrate = async ({firestore, FieldValue}) => {
    await firestore.collection('name').add({key: FieldValue.serverTimestamp()});
};

Typed Migrations

For type checking and Intellisense, there are two options:

TypeScript

1. Ensure ts-node is installed

2. Define a ts-node configuration block inside your tsconfig.json file:

   {
     "ts-node": {
       "transpileOnly": true,
       "compilerOptions": {
         "module": "commonjs"
       }
     }
   }

3. Create a migration

    // ./migrations/v0.0.1__typescript-example.ts
   
    import { MigrateOptions } from 'fireway';
   
    export async function migrate({firestore} : MigrateOptions) {
        await firestore.collection('data').doc('one').set({key: 'value'});
    };

4. Run fireway migrate with the require option

   $ fireway migrate --require="ts-node/register"

JSDoc

Alternatively, you can use JSDoc for Intellisense

/** @param { import('fireway').MigrateOptions } */
module.exports.migrate = async ({firestore}) => {
    // Intellisense is enabled
};

Running locally

Typically, fireway expects a --projectId option that lets you specify the Firebase project associated with your Firestore instance against which it performs migrations. However, most likely you'll want to test your migration scripts locally first before running them against your actual (presumably, production) instances. If you are using the Firestore emulator, define the FIRESTORE_EMULATOR_HOST environment variable, e.g.:

export FIRESTORE_EMULATOR_HOST="localhost:8080"

The firestore node library will connect to your local instance. This way, you don't need a project ID and migrations will be run against your emulator instance. This works since fireway is built on the firestore node library.

Migration logic

1. Gather all the migration files and sort them according to semver
2. Find the last migration in the fireway collection
3. If the last migration failed, stop. (remove the failed migration result or restore the db to continue)
4. Run the migration scripts since the last migration

Migration results

Migration results are stored in the fireway collection in firestore

// /fireway/3-0.0.1-example

{
  checksum: 'fdfe6a55a7c97a4346cb59871b4ce97c',
  description: 'example',
  execution_time: 1221,
  installed_by: 'system_user_name',
  installed_on: firestore.Timestamp(),
  installed_rank: 3,
  script: 'v0.0.1__example.js',
  success: true,
  type: 'js',
  version: '0.0.1'
}

Contributing

# To install packages and firestore emulator
$ yarn
$ yarn setup

# To run tests
$ yarn test

License

MIT