Meadow Migration Manager

0.0.13 verified Sat Apr 25 auth: no javascript

Meadow Migration Manager is a CLI, Web, and Terminal UI tool for managing database schema migrations within the Meadow ecosystem. As of version 0.0.13, it supports MySQL, PostgreSQL, MSSQL, and SQLite through pluggable providers. It provides a complete pipeline from MicroDDL schema definition via Stricture compilation, diffing between schema versions, SQL migration generation for target dialects, and live database deployment. Key differentiators include a multi-interface approach (CLI with 11 commands, blessed-based TUI, and interactive flow diagrams) and deep integration with Meadow data access libraries.

Common errors

error TypeError: MeadowMigrationManager is not a constructor ↓

cause Using ES module import syntax which is not supported; the package only exports a CommonJS module.

fix

Use const MeadowMigrationManager = require('meadow-migrationmanager'); instead of import.

error Cannot find module 'stricture' ↓

cause Missing peer dependency stricture which is required for DDL compilation.

fix

Install the missing dependency: npm install stricture.

Warnings

breaking Service providers are accessed via `instantiateServiceProvider` method, not as named exports from the package. ↓

fix Always create a MeadowMigrationManager instance first and use its method to obtain service instances.

gotcha The package does not provide TypeScript type definitions; all APIs are dynamically typed. ↓

fix Use JavaScript or manually create TypeScript declaration files if type safety is required.

gotcha Database connections and schema library data are stored in-memory and not persisted unless explicitly configured with a storage provider. ↓

fix Configure a persistent storage backend via the configuration object when instantiating MeadowMigrationManager.

Install

npm install meadow-migrationmanager

yarn add meadow-migrationmanager

pnpm add meadow-migrationmanager

Imports

MeadowMigrationManager

wrong

import MeadowMigrationManager from 'meadow-migrationmanager';

correct

const MeadowMigrationManager = require('meadow-migrationmanager');

This package does not ship ES module exports; use CommonJS require.

SchemaLibrary

wrong

const { SchemaLibrary } = require('meadow-migrationmanager');

correct

const tmpManager = new MeadowMigrationManager({}); const schemaLib = tmpManager.instantiateServiceProvider('SchemaLibrary');

Service providers are accessed via instantiateServiceProvider method, not direct exports.

StrictureAdapter

wrong

const { StrictureAdapter } = require('meadow-migrationmanager');

correct

const tmpManager = new MeadowMigrationManager({}); const stricture = tmpManager.instantiateServiceProvider('StrictureAdapter');

Same as SchemaLibrary; use the factory method.

ConnectionLibrary

const tmpManager = new MeadowMigrationManager({}); const connLib = tmpManager.instantiateServiceProvider('ConnectionLibrary');

Access via instantiateServiceProvider with the string 'ConnectionLibrary'.

Quickstart

Demonstrates schema creation, DDL compilation, and basic diffing between two schema versions using the programmatic API.

const MeadowMigrationManager = require('meadow-migrationmanager');

// Instantiate the manager with optional configuration
const tmpManager = new MeadowMigrationManager({});

// Access the schema library service
const schemaLib = tmpManager.instantiateServiceProvider('SchemaLibrary');

// Add a MicroDDL schema from a string
schemaLib.addSchema('bookstore', '!Book\n@IDBook\n$Title 200\n$Genre 128\n');

// Compile the DDL via Stricture
const stricture = tmpManager.instantiateServiceProvider('StrictureAdapter');
stricture.compileDDL(schemaLib.getSchema('bookstore').DDL, (pError, pSchema) => {
  if (pError) {
    console.error('Compilation error:', pError);
    return;
  }
  console.log('Compiled tables:', Object.keys(pSchema.Tables));
});

// Add a second version and diff
schemaLib.addSchema('bookstore-v2', '!Book\n@IDBook\n$Title 256\n$Genre 64\n$Price 10,2\n');
stricture.compileDDL(schemaLib.getSchema('bookstore-v2').DDL, (err2, schema2) => {
  if (!err2) {
    const diff = tmpManager.instantiateServiceProvider('DiffEngine');
    diff.diffSchema(schemaLib.getSchema('bookstore'), schemaLib.getSchema('bookstore-v2'), (dErr, dResult) => {
      console.log('Added tables:', dResult.Added);
      console.log('Removed tables:', dResult.Removed);
      console.log('Modified tables:', dResult.Modified);
    });
  }
});