auto-upgrade syntax in default installer script broken

[WilliamLoy]

Expected behavior:
default-installer should install teleport-ent-updater package if set to true
Current behavior:
This logic is ignored because the double = and double { fail in sh, which the script uses in its shebang #!/bin/sh.

if [[ \"{{ .AutomaticUpgrades }}\" == \"true\" ]];

This does however work in bash.

Bug details:

• Teleport version: 13.3.9
• Recreation steps: test double brackets and double equal signs in sh
• Debug logs

[marcoandredinis]

I don't think the double { is the issue here. It is filled by some variable before being evaluated by a shell.
The double = should not be an issue as well 🤔

sh-3.2$ if [[ "x" == "x" ]]; then echo "a"; fi
a
sh-3.2$

Do you have an error we can look at? Or the sh version in use? Maybe some older version did not accept this syntax.

Anyway, I think we should use the same shebang as agentless-installer.sh.tmpl:

#!/usr/bin/env bash

[zmb3]

@WilliamLoy friendly ping on this one

[WilliamLoy]

I'm still waiting to get the error back on this and I haven't yet reproduced it myself. I'll update you when I have the additional needed details.