Issue
To show my team how the app that I am building is progressing, I created a small dev server on google cloud compute engine. This server is usually switched off to save cost and only is switched on when we are working together. I am developing and pushing to a git repo when the server is not on. When I start the server, the latest changes should be pulled, the node packages installed and the node server should be started. To do this I have created the following startup script:
#! /bin/bash
cd /to/my/server/folder
git pull
sudo npm install --no-progress
nohup node src/ &
I have created an ssh key and added that as a read only deploy key in my gitlab account on this particular repo. The script is tested on the server and works totally fine. Now the fun part. When the script is run as a startup script (https://cloud.google.com/compute/docs/startupscript) it doesn't work. The error:
permission denied (public key)
fatal: could not read from repo make sure it exists.
I tried these fixes: Getting permission denied (public key) on gitlab. The problem being that they can not pull git repos in general. In my case it works fine from command line, it works fine from shell script, but it just doesn't work from startup script.
I also tried a whole bunch of other stuff on the whole spectrum from 'could be it' to 'a wild guess'. Clearly there is something I am missing here. Could anyone help me out?
Solution
Finally found the answer here: https://superuser.com/a/868699/852795. Apparently something goes wrong with the SSH keys that are used in a google startup script. The solution is to explicitly tell git what key to use. Like this: GIT_SSH_COMMAND="ssh -i ~/.ssh/id_rsa" git pull.
Answered By - Imre_G Answer Checked By - Katrina (WPSolving Volunteer)