Fail hard on first error in batch script

Bash generally keeps executing code line by line even
if any of the lines fail. For example, if your path is
not set properly, `batchspawner-singleuser` will not
be found by `which`. This should terminate execution.
However, without `set -e`, execution will just continue
and fail with a different error.

This patch does `set -euo pipefail` for all submission
scripts. This causes them to fail on:

1. Any non-zero command return code (-e)
2. On undefined environment variables (-u)
3. Treat failures in any part of a pipeline as failure,
   rather than just the last command (-o pipefail)

Author: yuvipanda

batchspawner/batchspawner.py

@@ -504,6 +504,8 @@ class TorqueSpawner(BatchSpawnerRegexStates):
 #PBS -v {keepvars}
 #PBS {options}
 
+set -euo pipefail
+
 {prologue}
 {cmd}
 {epilogue}
@@ -543,6 +545,8 @@ class PBSSpawner(TorqueSpawner):
 #PBS -v {{keepvars}}
 {% if options %}#PBS {{options}}{% endif %}
 
+set -euo pipefail
+
 {{prologue}}
 {{cmd}}
 {{epilogue}}
@@ -598,6 +602,8 @@ class SlurmSpawner(UserEnvMixin,BatchSpawnerRegexStates):
 {% endif %}{% if reservation%}#SBATCH --reservation={{reservation}}
 {% endif %}{% if options    %}#SBATCH {{options}}{% endif %}
 
+set -euo pipefail
+
 trap 'echo SIGTERM received' TERM
 {{prologue}}
 which jupyterhub-singleuser
@@ -671,6 +677,8 @@ class GridengineSpawner(BatchSpawnerBase):
 #$ -v {keepvars}
 #$ {options}
 
+set -euo pipefail
+
 {prologue}
 {cmd}
 {epilogue}
@@ -761,6 +769,8 @@ class LsfSpawner(BatchSpawnerBase):
 #BSUB -o {homedir}/.jupyterhub.lsf.out
 #BSUB -e {homedir}/.jupyterhub.lsf.err
 
+set -euo pipefail
+
 {prologue}
 {cmd}
 {epilogue}