Extract nested entries from an array

[cmoulliard]

The following "job1.yaml" file is a typical example describing for a github workflow the jobs and steps to be executed: https://docs.github.com/en/actions/using-workflows/about-workflows#create-an-example-workflow

In order to get from a yaml flow, the list of the job's names and their step's names, I'm wondering how jq could help me here

Sample:

name: Create Release

jobs:
  preparation:
    name: Preparation
    steps:
      - name: Checkout repo
        uses: actions/checkout@v4

      - name: Get stack names and USN support
        id: get-stack-names

      - name: Get Repository Name

  poll_images:
    name: Poll Images
    steps:
      - name: Find and Download Previous build image hash code of stack ${{ matrix.stacks.build_image }}
        if: ${{ matrix.stacks.create_build_image == true }}

      - name: Find and Download Previous run image hash code of stack ${{ matrix.stacks.run_image }}

What I expect to get (to document a project) is the following result (which could also be enriched with solme additional fields like if: etc:

jobs:
  name: preparation
  steps:
      - name: Checkout repo
      - name: Get stack names and USN support
      - name: Get Repository Name
   ...
  name: poll_images
  steps:
      - name: Find and Download Previous build image hash code of stack ${{ matrix.stacks.build_image }}
      - name: Find and Download Previous run image hash code of stack ${{ matrix.stacks.run_image }}
    ...  

The following code extracts well the job name but don't include the list of the steps

yq '.jobs[] as $job ireduce (""; (. + " ") + $job.name)' $YAML_DIR/flow.yaml
 Preparation Poll Images

[mikefarah]

You can do it like this:

yq '.jobs |= [.[]] | .jobs[].steps[] |= pick(["name"])' data1.yaml

name: Create Release
jobs:
  - name: Preparation
    steps:
      - name: Checkout repo
      - name: Get stack names and USN support
      - name: Get Repository Name
  - name: Poll Images
    steps:
      - name: Find and Download Previous build image hash code of stack ${{ matrix.stacks.build_image }}
      - name: Find and Download Previous run image hash code of stack ${{ matrix.stacks.run_image }}

Explanation:

• .jobs |= [.[]]; Update the jobs map (w.r.t to itself); setting jobs to be an array of all the map values. This works because .[] on a map matches all the map values, wrapping that with[.[]] makes it an array of all the values.
• .jobs[].steps[] |= pick(["name"]); from each of the step elements, pick the name field

[ccoVeille]

So this is a the equivalent of a to_entries where you are only looking for the values and the you are not interested in the keys

[.[]]

Am I right?

[cmoulliard]

So the syntax your are proposing looks a bit similar to what we use using jq ;-)

yq -o=json eval $FLOW_DIR/create-release.yml | jq -r '
  .jobs
  | to_entries
  | .[]
  | "\(.key):\n\(.value.steps
  	| map(
      	if .if then
        	"  - \(.name) \n	if: \(.if)"
      	else
        	"  - \(.name)"
      	end
    	)
  	| join("\n")
	)"
'