Automatically generates migration files from your sequelize models

sequelize-schema-file-generator.js

/*
check next problenm:

Property and value:
references
defaultValue
onDelete
onUpdate

Tyoes:
Sequelize.ENAM
Sequelize.ARRAY
Sequelize.NOW
*/

const models = require("../src/models")
const Sequelize = require("sequelize")
const fs = require("fs")


const sequelize = new Sequelize(
  'database',
  'user',
  'pass',
  {
    host: '127.0.0.1',
    dialect: 'postgres',
  }
);

const cliArgs = process.argv.slice(2)

if (cliArgs.length === 0) {
  console.log(`
  Missing required arguments: dirname

  Before create dirname. Script won't do it for you

  Example: node file.js dirname
`)
  return
}


const dirname = cliArgs[0]


for (let modelName in models) {

  if (modelName.toLocaleLowerCase() === 'sequelize') continue

  const model = models[modelName]

  let attributes = model.rawAttributes;

  for (let column in attributes) {
    delete attributes[column].Model;
    delete attributes[column].fieldName;
    delete attributes[column].field;
    for (let property in attributes[column]) {
      if (property.startsWith('_')) {
        delete attributes[column][property];
      }
    }

    if (typeof attributes[column]['type'] !== 'undefined') {

      if (
           typeof attributes[column]['type']['options'] !== 'undefined' 
        && typeof attributes[column]['type']['options'].toString === 'function'
      ) {
        attributes[column]['type']['options'] = attributes[column]['type']['options'].toString(sequelize);
      }

      if (
        typeof attributes[column]['type'].toString === 'function'
      ) {

        if (attributes[column]['type'].toString(sequelize).includes('TIMESTAMP')) {
          attributes[column]['type'] = 'Sequelize.DATE'
        }
        else if (attributes[column]['type'].toString(sequelize) === 'VARCHAR(255)') {
            attributes[column]['type'] = 'Sequelize.STRING'
        }
        else if (attributes[column]['type'].toString(sequelize).includes('VARCHAR')) {
          attributes[column]['type'] = `Sequelize.STRING(${attributes[column]['type']._length})`
        }
        else {
          attributes[column]['type'] = 'Sequelize.' + attributes[column]['type'].toString(sequelize);
        }

      }

    }

  }

  let schema = JSON.stringify(attributes, null, 2);
  let tableName = models[modelName].tableName;

  schema = schema.split('\n').map((line) => ' '.repeat(6) + line).join('\n');

  schema = schema.replace(/"/g, '', )

  // console.log({ tableName, schema })

  let template = `'use strict';
module.exports = {
    up: async (queryInterface, Sequelize) => {
      await queryInterface.createTable('${tableName}', ${schema}
      )
    },
    down: async (queryInterface, Sequelize) => {
      await queryInterface.dropTable(${tableName});
    }
};`

  let d = new Date();

  let filename = [d.getFullYear(), d.getMonth() + 1, d.getDate(), d.getHours(), d.getMinutes(), d.getSeconds()]
    .map((num) => num <= 60 && (num + 100).toString().substring(1) || num)
    .join('') + `-${models[modelName].tableName}`;

  fs.writeFileSync(`./${dirname}/${filename}.js`, template);
};

console.log('Finished!')