feat: create a client factory and an request example for the db

back-end/src/db/db_client.ts

@@ -0,0 +1,23 @@
+import pg from 'pg';
+
+const db_user = process.env.DB_USER ?? "admin";
+const db_password = process.env.DB_PASSWORD ?? "admin";
+const db_name = process.env.DB_NAME ?? "briques";
+const db_host = process.env.DB_HOST ?? "localhost";
+const db_port = parseInt(process.env.DB_PORT ?? "5432");
+
+console.log("=== DB CONFIG ===");
+console.log(`DB_USER:\t\t${db_user}`);
+console.log(`DB_PASSWORD:\t${db_user}`);
+console.log(`DB_NAME:\t\t${db_name}`);
+console.log(`DB_HOST:\t\t${db_host}`);
+console.log(`DB_PORT:\t\t${db_port}`);
+
+
+export const new_client = () => new pg.Client({
+  user: db_user,
+  password: db_password,
+  database: db_name,
+  host: db_host,
+  port: db_port,
+});

back-end/src/db/index.ts

@@ -0,0 +1,16 @@
+import { new_client } from './db_client';
+
+async function example_request() {
+  const client = new_client();
+  await client.connect();
+
+  const res = await client.query('SELECT $1::text as message', ['Hello world!']);
+  const message = res.rows[0].message;  // Hello world!
+  await client.end();
+
+  return message;
+}
+
+export default {
+  example_request,
+};