Example test with db-api agnostic usage

index.js

const R = require('ramda');
const dbFn = require('./sql-db');
const shipmentModelFn = require('shipment-model');

const db = dbFn();
const shipmentModel = shipmentModelFn(db.create);

// provide shipmentModel to the controller or something...

shipment-model.js

'use strict';
const R = require('ramda');

const exportFn = (dbCreate) => {
  return {
    create: (shipmentData) => {
      const id = dbCreate(shipmentData);
      return R.merge(shipmentData, {id: id});
    },
  };
};

shipment-model.spec.js

'use strict';

const modelFn = require('./shipment-model');

describe('shipment model', () => {
  it('creates shipments using provided shipment data', () => {
    const dbCreate = jasmine.createSpy('dbCreate');
    const model = modelFn(dbCreate);
    model.create({foo: 'bar'});
    expect(dbCreate).toHaveBeenCalledWith({foo: 'bar'});
  });
  
  it('provides a shipment id when creating a shipment', () => {
    const dbCreate = jasmine.createSpy('dbCreate').and.returnValue(4);
    const model = modelFn(dbCreate);
    const result = model.create({foo: 'bar'});
    expect(result.id).toEqual(4);
  });
});

sql-db.js

'use strict';

const sqlLibrary9000 = require('sql-library-9000');

const dbFn = () => {
  return {
    create: (tableName, data) => {
      const sqlValues = R.map((key, value) => '(' + key + ') = ' + value);
      const sqlValuesClause = R.join(' ', sqlValues);
      // sql injection can happen here, but contrived example
      const id = sqlLibrary9000.exec('INSERT INTO ' + tableName + ' VALUES ' + sqlValuesClause + ';');
      return id;
    }
  };
};

module.exports = dbFn;