Can't authenticate with a blank (empty string) password

[dlongley]

The following check causes authentication with a blank password to be skipped resulting in a 'Error setting TTL index on collection' error when later trying to ensure the indexes exist. This occurs on mongodb configurations that require strict authentication. This was noticed in a dev environment where the password used was just the empty string ('').

        if (options.username && options.password) {
          db.authenticate(options.username, options.password, function () {
            self._get_collection(cb);
          });
        } else {
          self._get_collection(cb);

https://github.com/kcbanner/connect-mongo/blob/master/lib/connect-mongo.js#L181

Perhaps the fix is simply:

        if (options.username && 'password' in options) {

But I'm not sure how much more comprehensive that check needs to be in this lib.

[dlongley]

It might also be useful to print out the actual error that occurs when ensureIndex fails as we first thought this was related to the race condition described in other issues (#65, #70, #80).