Could not load the default credentials? (Node.js Google Compute Engine tutorial)

Question

SITUATION:

I follow this tutorial: https://cloud.google.com/nodejs/tutorials/bookshelf-on-compute-engine

Everything works fine until I do

Answer 1

you may find youself in another part of the world -- and land here. I'm adding to a three year old question because its keywords matched my issue and the preceding answers helped me although none describe my issue

firebase deploy --only functions --debug

produced

[2020-12-02T08:31:50.397Z] FirebaseError: HTTP Error: 429, Unknown Error
Error: Could not read source directory. Remove links and shortcuts and try again.

I could not find anything wrong with the source directory. But that was all so many tiny fish.

Examining the error in detail, from the top, lead to:

Our systems have detected unusual traffic from your computer network.  This page checks to see if it's really you sending the requests, and not a robot. 
The block will expire shortly after those requests stop.  

Out of curiosity and exhaustion, I waited first. The wait reset duration is > than 30 minutes. So i pursued the captcha to prove my enduring humanity which did register eventually after some oauth warnings.