Node mongodb: Error: connection closed due to parseError

Question

Using the native 'mongodb' npm package, I'm receiving

Error: connection closed due to parseError

When making a very basic query:

 collections.myCollection.findOne({id: someID}, function (err, repo) {
    ...  
 })

The weird thing is, the exact same query has run before. Types are identical for each query, etc.

Answer 1

Answering my own question to hopefully stop the next person from tearing their hair out:

As noted here, this error message is useless and doesn't relate to the actual problem. The production Mongo driver throws away all errors in a catch block.

To find what the error actually is:

• open your node_modules/mongodb

• find server.js

• look for mongoReply.parseBody

• log the err to see something actually useful.

In my case:

ReferenceError: collection is not defined

Edit: Node MongoDB native 1.4 is now stable, and includes a fix to this bug.

Answer 2

For people who are using mongoose instead mongodb can check in the following location for the same.

/node_modules/mongoose/node_modules/mongodb/lib/mongodb/connection