argo list -o json should output JSON when no workflows found

[Goorzhel]

Summary

Expected:

bash-5.2# argo list -o json
[]

Actual:

bash-5.2# argo list -o json
No workflows found

Which causes:

bash-5.2# argo list -o json | jq .
parse error: Invalid numeric literal at line 1, column 3

Use Cases

I have a Bash script that pipes to jq to check for workflows with parameters identical to the one it's about to submit -- if there is one, skip submission.

submit() {
  # snip
  existing=$(argo list -o json | \
    jq -r '.[]
      | select(.status.phase=="Running" or .status.phase=="Succeeded")
      | .spec.arguments.parameters[]
      | select(.name=="filename")
      | .value')

  if grep -qF "$filename" <<< "$existing"; then
    echo "Found existing workflow for $filename"
    return
  fi
  # snip
}

Perhaps there is a better way, but this is the one I've cobbled together.

Version

bash-5.2# argo version
argo: v3.4.6
  BuildDate: 2023-03-31T19:53:49Z
  GitCommit: 988706dd131cf98808f09fb7cc03780e2af94c73
  GitTreeState: clean
  GitTag: v3.4.6
  GoVersion: go1.18.10
  Compiler: gc
  Platform: linux/amd64

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[OneCricketeer]

You could check $? value if it's zero as a workaround. For example, you're not handling error case where Argo workflow server is down.

[Goorzhel]

In a sense, I am: I accidentally left out the script's set -e in that snippet.