Pipelining in github workflows

How do I use pipelining in github workflows? I was having difficulty while finding patterns from from github.event.issue.body.

Below one is the one I tried.enter image description here While running it, I am getting the error "-e: command not found".

This seems to be because of the grep commands and their format. Basically there are some syntax issues (with how you are assigning the values to the varibale from stdout) and then the grep command will search for files as per your given format. Even if you correct the syntax this will fail because there are no such file corresponding to the output of ${{ github.event.issue.body }}. To avoid this file search you can use pipes. You have whitespaces in your env assignment, but it should be echo "a=b" instead of echo "a = b". Another thing is, '[Proposal]' in the contains query might always evaluate to false (I am not a hundred percent sure regarding this but it indeed was so when I tested it out) so you might want to change it to 'Proposal' (or 'proposal' as it is case insensitive). Hence you can rewrite the whole thing like this:

- name: <your-step-name>
  run: |
    echo "has_proposal_label=${{ contains(github.event.issue.title, 'proposal') }}" >> $GITHUB_OUTPUT
    category3=$(echo "${{ github.event.issue.body }}" | grep -e "Category" -A2 | grep -v "Category" | grep "\S")
    echo "category<<EOF" >> $GITHUB_OUTPUT
    echo "$category3" >> $GITHUB_OUTPUT
    echo "EOF" >> $GITHUB_OUTPUT

This assumes your category output will have multiple lines, but if you don't have and it is a single line, then you can simply do echo "category=$category3" >> $GITHUB_OUTPUT.