[google app engine version cleanup script]

gae_version_cleanup.sh

#!/usr/bin/env bash

###########################################################
# Use this script to delete old versions of GAE services. #
# Requires gcloud SDK to be installed and authorized.     #
# Usage:                                                  #
# GCP_PROJECT=my_project GAE_SERVICE=my_service KEEP=5 \  #
# ./gae_version_cleanup.sh                                #
###########################################################

# check project is specified
if [ "$GCP_PROJECT" = "" ]; then
  echo '`$GCP_PROJECT` variable required'
  exit 1
fi

# check service is specified
if [ "$GAE_SERVICE" = "" ]; then
  echo '`$GAE_SERVICE` variable required'
  exit 1
fi

# check number of versions to keep is specified
if [ "$KEEP" = "" ] || [ "$KEEP" = 0 ]; then
  echo '`$KEEP` variable required'
  exit 1
fi

# fetch versions
VERSIONS=$(gcloud app versions list -q --project="$GCP_PROJECT" --service="$GAE_SERVICE" | cut -d ' ' -f3)
# printf "Current versions:\n%s\n\n" "$VERSIONS"

# count total number of versions
TOTAL=$(echo "$VERSIONS" | wc -l)
printf "Total versions of $GAE_SERVICE: %d.\n" "$TOTAL"

# get number of versions to delete
COUNT=$((TOTAL - KEEP))
printf "Keeping %d versions of $GAE_SERVICE.\n" "$KEEP"
printf "Deleting %d versions of $GAE_SERVICE.\n\n" "$COUNT"
COUNT=$((TOTAL - KEEP + 1))

# get the list of versions to delete
TO_DELETE=$(echo "$VERSIONS" | head -n $COUNT)
printf "Versions to delete:%s\n\n" "$TO_DELETE"

TO_DELETE=$(echo "$TO_DELETE" | tr '\n' ' ')
printf 'Executing: `gcloud app versions delete --project="%s" --service="%s" %s`\n\n' "$GCP_PROJECT" "$GAE_SERVICE" "$TO_DELETE"

# delete versions
{
  gcloud app versions delete -q --project="$GCP_PROJECT" --service="$GAE_SERVICE" $TO_DELETE
} || {
  echo "Failed to delete $GAE_SERVICE versions from $GCP_PROJECT"
  exit 1
}