SyntaxError: Cannot use import statement outside a module

For the secret game I am developing, I needed a database to store User and Profile data. The game’s backend server is developed using Node.js and Typescript, and to simplify connecting to the MySQL database, I wanted to use TypeORM.

TypeORM is awesome. Previously, I had to create the database from scratch and I connected to the database directly and subsequently executed carefully prepared sql queries with parameters. With TypeORM I can specify entities, add columns with specific qualities. It has a synchronize option that automatically updates the database based on your entities whenever you start your application.

For a production database, however, this sounds a tad dangerous. With TypeORM it is also possible to generate migrations when the synchronize option is turned off.

So, that’s what I wanted to do: Generate migrations and update database in a structured and organized manner. Using the globally installed npm package TypeORM CLI (Command Line Interface), this should be as easy as executing the following command:

// bash
typeorm migration:generate -n

However, this returned an error:

SyntaxError: Cannot use import statement outside a module

Apparently, the TypeORM CLI does not work well with my package.json, tsconfig.json or ts-node settings. I still have not figured out why not, but I am happy to say I have found a solution to generate my migrations, loosely based on several Stackoverflow entries, which I unconveniently cannot find at the moment.

Behold:

Several Stackoverflow findings gave the advice of using CommonJS as the module setting in the tsconfig.json file:

// File: tsconfig.json
{
  "compilerOptions": {
    // Other settings
    "module": "CommonJS"
  }
}

Then, instead of using the globally installed TypeORM CLI, I use the locally installed CLI by adding it as a npm script:

// File: package.json
// Do note: I use ts-node to execute the CLI,
// so do not forget to install ts-node as well.
{
  "scripts": {
    "start": "npx ts-node server.ts",
    "dev": "nodemon",
    "typeorm:local": "ts-node ./node\_modules/typeorm/cli.js"
  },
}

Then, to execute this script with the correct parameters, I execute the following command in the shell:

// bash
npm run typeorm:local -- migration:generate -n AddNewTable

I am also very happy to have found out [link] about the -- double hyphens that allow for supplying parameters to a script configured in package.json.

Now I can generate migrations every day.

• node-js
• npm
• typeorm
• typescript