slave/skia_slave_scripts/check_compute_engine_disk_usage.sh

#!/bin/bash
#
# Logs into the specified Skia compute engine instance, parses out the
# persistent disk usage and compares it against the threshold.
#
# The SKIA_COMPUTE_ENGINE_HOSTNAME environment variable is the hostname of the
# compute engine instance we want to check. The PERSISTENT_DISK_NAME is the
# mounted path of the disk we want to check.
#
# Sample Usage:
#  SKIA_COMPUTE_ENGINE_HOSTNAME=skia-master-a.c.skia-buildbots.google.com.internal \
#  PERSISTENT_DISK_NAME=/home/default/skia-master \
#  DELETE_TRYBOT_DIRS=True \
#  bash check_compute_engine_disk_usage.sh
#
# Can also optionally specify the environment variable THRESHOLD (default 90).
#

THRESHOLD=${THRESHOLD:-90}

# Check to see if the script can log into the compute engine instance.
ssh -o UserKnownHostsFile=/dev/null -o CheckHostIP=no -o \
StrictHostKeyChecking=no -p 22 $SKIA_COMPUTE_ENGINE_HOSTNAME 'df -h'
ret_code=`echo $?`
if [ "$ret_code" -ne 0 ]; then
  echo -e "There was an error logging into the compute engine instance! Return code: $ret_code"
  exit $ret_code
fi

function check_disk_space_usage {
  complete_output=`ssh -o UserKnownHostsFile=/dev/null -o CheckHostIP=no -o \
    StrictHostKeyChecking=no -p 22 $SKIA_COMPUTE_ENGINE_HOSTNAME 'df -h' | \
    grep $PERSISTENT_DISK_NAME`; IFS=' ' v=($complete_output); \
  percent_used=${v[4]/\%/}
  echo $percent_used
}

# Log into the compute engine instance and parse the percentage used of the
# persistent disk.
percent_used=`check_disk_space_usage`
if [ "$percent_used" -lt "$THRESHOLD" ]; then
  echo -e "\nThe percentage used ($percent_used%) is below the threshold ($THRESHOLD%).\n"
  exit 0
else
  echo -e "\nThe percentage used ($percent_used%) is at or beyond the threshold ($THRESHOLD%).\n"
  if [[ ! -z "$DELETE_TRYBOT_DIRS" ]]; then
    DELETE_CMD="rm -rf ~/skia-slave/buildbot/skiabot-linux-compile-vm-*/buildbot/third_party/chromium_buildbot/slave/*-Trybot; rm -rf
~/skia-slave/buildbot/skiabot-linux-compile-vm-*/buildbot/third_party/chromium_buildbot/slave/*.log.*"
    ssh -o UserKnownHostsFile=/dev/null -o CheckHostIP=no -o \
      StrictHostKeyChecking=no -p 22 default@$SKIA_COMPUTE_ENGINE_HOSTNAME "$DELETE_CMD"
    echo "Deleted the Trybot builder directories."
    percent_used=`check_disk_space_usage`
    echo "The percentage used is now: $percent_used%"
  else
    echo -e "Please make room on the compute engine instance by deleting unneeded files.\n"
    exit 1
  fi
fi