'Which' not in dependencies

[johandroz]

Bug report

System info: InfluxDB 1.3.6

Steps to reproduce:

I was creating a container with influxdb with a fedora 26 base. It doesn't come with many "standard utilities" such as which.
Thus this part of the post install script will fail :
if [[ -f /etc/redhat-release ]]; then
# RHEL-variant logic
which systemctl &>/dev/null
if [[ $? -eq 0 ]]; then
install_systemd
else
# Assuming sysv
install_init
install_chkconfig
fi

Additional info: We can resolve this by installing which before installing influx.

[phemmer]

Alternatively, since this is obviously a bash script, you could do command -v systemctl, since command is a bash built-in. Or systemctl --version.

And since we're on the subject, the use of $? is unnecessary.

if command -v systemctl >/dev/null; then
  install_systemd
else
 ...

[CMajeri]

@phemmer You're right, but the issue is that this is from the postinstall script of the RPM package. This isn't a homebrew install script :)
It assumes which is installed, but it might not be in small environments i.e. a container.

Assuming I run a fedora container that comes without which, I'd expect a dnf install to install the systemd service file (yes, running systemd in a container is a peculiar use-case, but it's a valid one nonetheless :).

I admit that environments without which that use systemd are very rare, which might be why this has gone unnoticed for so long.

[phemmer]

@CMajeri

This isn't a homebrew install script

Actually it is: https://github.com/influxdata/influxdb/blob/master/scripts/post-install.sh#L48

[CMajeri]

I meant it's from influx, @johandroz didn't write it himself!