index.js

const WebSocket = require('ws');
const schema = require('enigma.js/schemas/12.20.0.json');
const enigma = require('enigma.js');

const host = process.env.ENGINE_HOST || 'localhost';
const port = 19076;

// create a new session:
const session = enigma.create({
  schema,
  url: `ws://${host}:${port}/app/engineData`,
  createSocket(url) {
    return new WebSocket(url);
  },
});

const postgresqlConnectionSettings = {
  qType: 'jdbc', // the name we defined as a parameter to engine in our docker-compose.yml
  qName: 'jdbc',
  qConnectionString:
   'CUSTOM CONNECT TO "provider=jdbc;driver=postgresql;host=postgres-database;port=5432;database=postgres"', // the connection string includes both the provider to use and parameters to it.
  qUserName: 'postgres', // username and password for the postgres database, provided to the GRPC-Connector
  qPassword: 'postgres',
};

const mysqlConnectionSettings = {
  qType: 'jdbc', // the name we defined as a parameter to engine in our docker-compose.yml
  qName: 'jdbc',
  qConnectionString:
  'CUSTOM CONNECT TO "provider=jdbc;driver=mysql;host=mysql-database;port=3306;database=airport"', // the connection string includes both the provider to use and parameters to it.
  qUserName: 'root', // username and password for the mysql database, provided to the GRPC-Connector
  qPassword: 'mysecretpassword',
};


async function loadData(app, connectionSettings) {
  const startTime = Date.now();

  const connectionId = await app.createConnection(connectionSettings);

  const script = `
    lib connect to 'jdbc';
    airports:
    sql SELECT * FROM airports;
    `;
  await app.setScript(script);
  await app.doReload();

  console.log(`Reload took: ${Date.now() - startTime} ms`);

  await app.deleteConnection(connectionId);
  await app.setScript('');
  await app.doSave();

  const tableData = await app.getTableData(-1, 100, true, 'airports');

  const tableDataAsString = tableData
    .map(row => row.qValue
      .map(value => value.qText)
      .reduce((left, right) => `${left}\t${right}`))
    .reduce((row1, row2) => `${row1}\n${row2}`);

  console.log(tableDataAsString);
}

async function load() {
  const appId = 'reloadapp.qvf';
  const global = await session.open();
  let app;

  try {
    const appInfo = await global.createApp(appId);
    app = await global.openDoc(appInfo.qAppId);
  } catch (e) {
    app = await global.openDoc(appId);
  }

  console.log('Loading from MySQL');
  try {
    await loadData(app, mysqlConnectionSettings);
  } catch (e) {
    console.log(`Failed to load data from MySQL with error: ${e}`);
    process.exit(1);
  }

  console.log('Loading from PostgreSQL');
  try {
    await loadData(app, postgresqlConnectionSettings);
  } catch (e) {
    console.log(`Failed to load data from PostgreSQL with error: ${e}`);
    process.exit(1);
  }

  await global.deleteApp(appId);

  await session.close();
}

load();