GCEでタグ情報を環境変数に持ってくる

tag.bash

#!/bin/bash

while read tag; do

  upper_tag=${tag^^}
  upper_underscore_tag=${upper_tag//-/_}
  export GCE_TAG_${upper_underscore_tag}=1
  
done < <( curl \
  -H "X-Google-Metadata-Request: True" \
  "http://metadata.google.internal/computeMetadata/v1/instance/tags?alt=text" 2>/dev/null )
# suppress pipelining http://stackoverflow.com/questions/13726764/bash-script-while-loop-subshell-dilemma

# and more 
#if [ -n "$GCE_TAG_PRODUCTION" ]; then
#  export RAILS_ENV=production
#fi
# ...