connection_pool.test.ts

import { once } from 'node:events';

import { expect } from 'chai';

import { type ConnectionPoolCreatedEvent, type Db, type MongoClient } from '../../mongodb';

describe('Connection Pool', function () {
  let client: MongoClient;
  let db: Db;
  afterEach(async function () {
    if (client) {
      if (db) {
        await db.dropDatabase();
      }
      await client.close();
    }
  });
  describe('Events', function () {
    describe('ConnectionPoolCreatedEvent', function () {
      context('when no connection pool options are passed in', function () {
        let pConnectionPoolCreated: Promise<ConnectionPoolCreatedEvent[]>;
        let connectionPoolCreated: ConnectionPoolCreatedEvent;
        beforeEach(async function () {
          client = this.configuration.newClient({}, {});
          pConnectionPoolCreated = once(client, 'connectionPoolCreated');
          await client.connect();

          connectionPoolCreated = (await pConnectionPoolCreated)[0];
        });

        it('the options field matches the default options', function () {
          expect(connectionPoolCreated).to.have.deep.property('options', {
            waitQueueTimeoutMS: 0,
            maxIdleTimeMS: 0,
            maxConnecting: 2,
            minPoolSize: 0,
            maxPoolSize: 100
          });
        });
      });

      context('when valid non-default connection pool options are passed in', function () {
        let pConnectionPoolCreated: Promise<ConnectionPoolCreatedEvent[]>;
        let connectionPoolCreated: ConnectionPoolCreatedEvent;
        const options = {
          waitQueueTimeoutMS: 2000,
          maxIdleTimeMS: 1,
          maxConnecting: 3,
          minPoolSize: 1,
          maxPoolSize: 101
        };
        beforeEach(async function () {
          client = this.configuration.newClient({}, options);
          pConnectionPoolCreated = once(client, 'connectionPoolCreated');
          await client.connect();

          connectionPoolCreated = (await pConnectionPoolCreated)[0];
        });

        it('the options field only contains keys and values matching the non-default options', function () {
          expect(connectionPoolCreated).to.have.deep.property('options', options);
        });
      });
    });
  });
});