test_typeorm.ts

import { createConnection, Connection, PrimaryColumn } from "typeorm";
import { Entity, Column } from "typeorm";

@Entity()
export class Test {
  @PrimaryColumn("integer")
  id!: string;
}

function sleep(ms: number) {
  return new Promise((resolve) => {
    setTimeout(resolve, ms);
  });
}

async function longQuery(connection: Connection) {
  try {
    console.log(await connection.query("SELECT pg_sleep(5)"));
  } catch (e) {
    console.error("caught ", e);
  }
}

async function borkedQuery(connection: Connection) {
  try {
    console.log(await connection.query("SELECT asdf;"));
  } catch (e) {
    console.error("borked caught ", e);
  }
}

async function main() {
  const connection = await createConnection({
    type: "postgres",
    host: "localhost",
    port: 5432,
    username: "postgres",
    password: "postgres",
    database: "test",
    entities: [Test],
    synchronize: true,
    poolErrorHandler: (err) => console.error("pool error: ", err),
    logging: true,
    extra: {
      min: 2,
      max: 2,
    },
  });

  while (true) {
    await longQuery(connection);
    await borkedQuery(connection);
    await sleep(1000);
  }
}

main().catch((err) => {
  console.error("main error", err);
});