Having Trouble Initializing Postgresql Database Through PG-Promise - postgresql

Question

I'm completely new to Express/Postgresql and I'm trying to learn them to create a web application. After some poking around, I decided that I wanted to develop my back-end with TypeScript. I successfully converted all my other files from JavaScript to TypeScript, but I still can't figure out how to initialize the pg-promise connection in TypeScript!
I've been trying to follow the TypeScript guidelines in this link here. https://github.com/vitaly-t/pg-promise/tree/master/typescript
// Initialize the PostGres database conneciton for use throughout
the entire application
import {IMain, IDatabase} from 'pg-promise';
import * as pgPromise from 'pg-promise';
const pgp: IMain = pgPromise({
query(e: any) {
console.log('QUERY RESULT:', e.query);
},
receive(data: any, result: any, e: any) {
console.log(`DATA FROM QUERY ${e.query} WAS RECEIVED.`);
}
});
const connection: any = {
host: 'localhost',
port: 5432,
database: 'RushHub',
user: 'RyanArifin',
password: null
}
const db: IDatabase<any> = pgp(connection);
export {
db
};
I currently am getting the error "TS2349: Cannot invoke an expression whose type lacks a call signature. Type 'typeof pgPromise' has no compatible call signatures." This error is coming from when I try to set my initialization options. Any help would be appreciated, thanks!

Answer 1

This is standard TypeScript configuration flag - esModuleInterop. When set to true, the import syntax is import pgPromise from 'pg-promise';, and when false, which is the default, the syntax is import * as pgPromise from 'pg-promise';.
The library gives you example for the default TypeScript configuration.