jsonbashyamlgithub-actionsjsonparser

GitHub Actions: How to pass toJSON() result to shell commands


So, I'm working with Github Actions on end-to-end testing. The setup I'm looking at is having one job retrieve a list of urls to be tested, and my second job creates a matrix with that list and tests them all. My problem here is that when I actually run my testing script, it has to be done from the command line, because I'm using Playwright. Therefore I can't use my matrix object directly; I have to output it to a JSON file. The problem is that toJSON creates invalid pretty-printed JSON when I output it to my file, which breaks my script. Here's my code:

name: <name>

on:
    push:
    workflow_dispatch:

jobs:
    fetch_strategic_urls:
        runs-on: ubuntu-latest
        outputs:
            urls: ${{ steps.req-urls.outputs.urls }}
        steps:
            - name: Request Urls
              id: req-urls
              run: |
                  export RESPONSE=$(
                    curl -X GET -H "Accept: application/json" <api-endpoint>)
                  echo "::set-output name=urls::$RESPONSE"
    run_tests:
        runs-on: ubuntu-latest
        strategy:
            matrix:
                url: ${{needs.fetch_strategic_urls.outputs.urls}}
        needs: fetch_strategic_urls
        steps:
            - ...
            - ...
            - run: |
                  ls
                  echo '${{ toJSON(matrix.url) }}' >> props.json
                  cat props.json
                  npm test
              working-directory: E2E.Tests

No matter which configuration of echo ${{matrix.url}} >> props.json I've tried (cat <<'EOF' > props.json ${{matrix.url}}, adding and removing quotes), it always produced JSON files that have no quotes, i.e.: { url: string } instead of {"url": "string"}, which is invalid. This is obviously pretty breaking behavior. I've seen a lot of people online recommending jq, but I don't see how I would use it in this case, since I doubt jq can parse a GitHub-type JSON object, which is necessary for me to use when sharding my jobs. Any help is greatly appreciated!


Solution

  • It's not easy to put a JSON doc directly in the command line. You can use env vars.

    - shell: bash
      env:
        JSON_DOC: ${{ toJSON(some.var) }}
      run: |
        printf '%s\n' "$JSON_DOC" > foo.json
        cat foo.json
        ...