How to I loop through AWS CLI output?

问题

I am trying to pass a list of values from a aws cli query to another command. Even though I have seen plenty of examples in AWS, when I try all the values come together:

  policy_versions=`aws iam list-policy-versions --query "Versions[].VersionId" --policy-arn $POLICY_ARN --output text`
  echo "policy_versions=$policy_versions"
  for ver in $policy_versions; do
    echo "first version: $ver"
  done

Which then prints out:

policy_versions=v3  v2  v1
first version: v3   v2  v1

My value of ver is the entire string, it should be v3 then v2 and v1. But It is instead: v3 v2 v1.

I cannot figure out what is wrong.

回答1:

I was able to reproduce your results and I traced the results to a difference between shell and zsh (which is now used as the default shell in MacOS).

Put simply, you can run this command to make it work the way you expect: setopt shwordsplit

For more details, see: iteration - Shell script - iterate over space separated words/characters (in zsh) - Stack Overflow

来源：https://stackoverflow.com/questions/62593695/how-to-i-loop-through-aws-cli-output