Setting up SQL Server 2012 (v11.0.0) in Node.JS v20.15.0 as Backend API or Data Access Layer Structure

Question

I need to set add-ons on my Flutter project, this is a Backend API using Node.JS which will serve as a middleman API for my Flutter project to retrieve and manage data from database in any platform (e.g., Android, iOS, Windows, and Web).

Now, my folder structure is,

backend-api/
  |- config/
  |  |- db.config.js // initialize the connection to mssql
  |  |- sequelize.config.js //add sequelize structure with db.config.js
  |- models/
  |  |- index.js         // Sequelize setup and model definitions
  |  |- random.text.model.js // Example model definition
  |- controllers/
  |  |- random.text.controller.js  // CRUD with MSSQL stored procedure operations for random text
  |- routes/
  |  |- random.text.routes.js      // Routes for random text CRUD SP's operations
  |- server.js //last setup which I will use later to add in my Flutter project to access my backend API

My problems are:

node:internal/modules/esm/resolve:265
throw new ERR_MODULE_NOT_FOUND(
^

Error [ERR_MODULE_NOT_FOUND]: Cannot find module 'C:\Users\userDir\Flutter\RandomText\backend-api\controllers\tutorial.controller.js' imported from C:\Users\userDir\Flutter\RandomText\backend-api\routes\random.text.routes.js

After I execute this command: node server.js to run it locally and test my backend API.

I appreciate any help you can provide.

I've set the prerequisites for my backend API, and also I've already used my SQL Server credentials to my other project which will be my basis that it will work as expected. I need the Node.JS integration to my Flutter project to serves as a data access level (DAL).

I prevented myself to provide the code as it seems to be unnecessary, because I wondering for some developer who had encountered the same error. What I need is to assess the solution you have applied and shared to this forum.

Again, thank you.

Answer 1

I've already resolved it by identifying the proper import and export of function variables from one class file to another. It was like exporting from where it was created and then importing it to where it should be used.

Using Node.js v20.15.0

import { sql, poolPromise } from '../config/db.config.js';

const manageData = async (req, res) => {
  //function logic here
}

export {
  manageData
};

import {
    manageData,
} from '../controllers/api.controller.js';

Also, I ensure that the package dependencies I need are properly added to my package.json file.

I've discovered that it was like creating my function within the project itself and using the export to expose that function to become discoverable to another node file through the use of import.

I hope it helps future readers!