const assert = require('assert');
const mongodb = require('mongodb');
const url = 'mongodb://mongo:27017,mongo:27018,mongo:27019/test?replicaSet=rs';
const options = {
    useNewUrlParser: true,
    readConcern: {
        level: 'majority'
    }
};

mongodb.connect(url, options, (error, client) => {
    assert.ifError(error);

    const db = client.db();
    const admin = new mongodb.Admin(db, client.topology);

    admin.serverInfo((error, info) => {
        assert.ifError(error);
        console.log('nodejs version: ' + client.topology.clientInfo.platform);
        console.log('client version: ' + client.topology.clientInfo.driver.version);
        console.log('server version: ' + info.version + ' (git: ' + info.gitVersion + ')');

        const session = client.startSession();
        const collection = client.db().collection('things');
        const options = {session: session};

        session.startTransaction();
        collection.insertOne({name: 'something'}, options, (error) => {
            assert.ifError(error);
            collection.findOne({name: 'something'}, options, (error, thing) => {
                assert.ifError(error);
            });
        });
    });
});

nodejs version: Node.js v10.13.0, LE
client version: 3.1.10
server version: 4.0.4 (git: f288a3bdf201007f3693c58e140056adf8b04839)
/app/node_modules/mongodb/lib/utils.js:132
      throw err;
      ^AssertionError [ERR_ASSERTION]: ifError got unwanted exception: Only the first command in a transaction may specify a readConcern
    at collection.findOne (/app/testcase.js:31:24)
    at err (/app/node_modules/mongodb/lib/utils.js:415:14)
    at executeCallback (/app/node_modules/mongodb/lib/utils.js:404:25)
    at handleCallback (/app/node_modules/mongodb/lib/utils.js:128:55)
    at cursor.next (/app/node_modules/mongodb/lib/operations/collection_ops.js:582:29)
    at err (/app/node_modules/mongodb/lib/utils.js:415:14)
    at executeCallback (/app/node_modules/mongodb/lib/utils.js:404:25)
    at handleCallback (/app/node_modules/mongodb/lib/utils.js:128:55)
    at cursor._next (/app/node_modules/mongodb/lib/operations/cursor_ops.js:186:21)
    at handleCallback (/app/node_modules/mongodb-core/lib/cursor.js:203:5)
    at queryCallback (/app/node_modules/mongodb-core/lib/cursor.js:248:25)
    at /app/node_modules/mongodb-core/lib/connection/pool.js:532:18
    at process._tickCallback (internal/process/next_tick.js:61:11)