Kevins-MDB-MBP:code kevarh$ cat broken.js
if (typeof rs.secondaryOk !== 'undefined') {
  rs.secondaryOk();
} else {
  rs.slaveOk();
}
printjson(db.getMongo().getDBNames());

Kevins-MDB-MBP:code kevarh$ mongo 127.0.0.1:27018 broken.js
MongoDB shell version v4.4.0
connecting to: mongodb://127.0.0.1:27018/test?compressors=disabled&gssapiServiceName=mongodb
Implicit session: session { "id" : UUID("bbe398b5-de9b-47ec-9182-f156b240cb9e") }
MongoDB server version: 4.4.3
[ "admin", "config", "local", "status" ]
Kevins-MDB-MBP:code kevarh$ mongosh 127.0.0.1:27018 broken.js
Current Mongosh Log ID:	6192a94e3efa8c88a52515e3
Connecting to:		mongodb://127.0.0.1:27018/test?directConnection=true&serverSelectionTimeoutMS=2000
Using MongoDB:		4.4.3
Using Mongosh:		1.1.2

For mongosh info see: https://docs.mongodb.com/mongodb-shell/

------
   The server generated these startup warnings when booting:
   2021-11-11T14:18:04.550-06:00: Access control is not enabled for the database. Read and write access to data and configuration is unrestricted
   2021-11-11T14:18:04.550-06:00: This server is bound to localhost. Remote systems will be unable to connect to this server. Start the server with --bind_ip <address> to specify which IP addresses it should serve responses from, or with --bind_ip_all to bind to all interfaces. If this behavior is desired, start the server with --bind_ip 127.0.0.1 to disable this warning
------

Loading file: broken.js
DeprecationWarning: .setSecondaryOk() is deprecated. Use .setReadPref("primaryPreferred") instead
Setting read preference from "primary" to "primaryPreferred"
MongoServerError: not primary and secondaryOk=false - consider using db.getMongo().setReadPref() or readPreference in the connection string