pg.Pool is not a constructor

Question

I have a google cloud function using this code and it gives the error TypeError: pg.Pool is not a constructor at exports.postgresDemo I have

    {
  "dependencies": {
    "pg": "^2.0.5"
  }
}

as the dependencies. I don't know if the error is in node or cloud functions

Please post that part of the snippet. Also, have you required pg? — SanSolo, Dec 18 '18 at 04:30
@SanSolo what snippet? I copied Google's sample code and put in the info for my postgresql database and it gives me that error. Yes I required pg. Thanks for your help — Andy Hay, Dec 19 '18 at 05:05
So the error is at this point? `pgPool = new pg.Pool(pgConfig)`? snippet because that's considered good practice instead of people having to go visit another page. Increases the chances of getting an answer — SanSolo, Dec 19 '18 at 05:10
I just checked the [documentation](https://node-postgres.com/features/pooling) for the pg package. There the require is not a variable, it is : `const { Pool } = require('pg')` — SanSolo, Dec 19 '18 at 05:17

score 4 · Accepted Answer · answered Dec 19 '18 at 06:16

Should have been obvious from your dependencies :

"dependencies": {
    "pg": "^2.0.5"
  }
}

I ran this:

const pg = require('pg')
const pool = new pg.Pool()
console.log(pool)

and got the expected result. Difference is, in my dependencies, I have :"pg": "^7.7.1". The google example you are using also uses a more recent version of pg. I tried to install your version to double check using npm install pg@2.0.5 but got the error: npm ERR! notarget No matching version found for pg@2.0.5 So upgrade pg and it will work

score 0 · Answer 2 · answered Apr 01 '23 at 19:19

For those who want or need to load the npm pg package as an ES6 module instead:

import pg from 'pg';
const { Pool } = pg;

const pool = new Pool({
  host: 'localhost',
  port: 5432,
  user: 'postgres',
  password: '********',
  database: 'postgres',
});

Related: Can I import the node-postgres module (pg) or is it CommonJS only?

pg.Pool is not a constructor

2 Answers2

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