Support converting yaml to properties

[eldada]

Please describe your feature request.
I have use cases where I want to flatten a yaml into a properties file format.

Describe the solution you'd like
If we have data.yml like:

a:
  array:
    - name: "element1"
      value: "value1"
    - name: "element2"
      value: "value2"
      sub-array:
        - sub1: "x"
        - sub2: "y"
        - sub3: "z"

And we run a command:

yq eval --prop data.yml'

it could output

a.array.0.name=element1
a.array.0.value=value1
a.array.1.name=element2
a.array.1.value=value2
a.array.1.sub-array.0.sub1=x
a.array.1.sub-array.1.sub2=y
a.array.1.sub-array.2.sub3=z

Describe alternatives you've considered
I wrote a bash script to do this with yq, but I think this can. (and should) be a built in feature of yq.

[mikefarah]

yq eval '.. | select((tag == "!!map" or tag == "!!seq") | not) | (path | join(".")) + "=" + .' examples/data1.yaml

Synopsis:

• recurse into everything
• filter out maps and arrays
• join the path array with '.'
• append "=" and the value

[daniel-liuzzi]

yq eval '.. | select((tag == "!!map" or tag == "!!seq") | not) | (path | join(".")) + "=" + .' examples/data1.yaml

Is it possible this doesn't work on Windows? I tried it on the exact same file as OP, and got an error:

> cat examples/data1.yaml
a:
  array:
    - name: "element1"
      value: "value1"
    - name: "element2"
      value: "value2"
      sub-array:
        - sub1: "x"
        - sub2: "y"
        - sub3: "z"

> yq eval '.. | select((tag == "!!map" or tag == "!!seq") | not) | (path | join(".")) + "=" + .' examples/data1.yaml
Error: Parsing expression: Lexer error: could not match text starting at 1:21 failing at 1:23.
        unmatched text: "!!"

In case it matters, I'm on PowerShell 7.1.3 and yq 4.6.2 (installed via scoop install yq.)

[mikefarah]

Powershell has it's own way of doing quotes https://mikefarah.gitbook.io/yq/usage/tips-and-tricks#quotes-in-windows-powershell

[daniel-liuzzi]

Managed to make it work by brute force: triple double quotes, geez, that's a lot of quotes!

yq eval '.. | select((tag == """!!map""" or tag == """!!seq""") | not) | (path | join(""".""")) + """=""" + .' examples/data1.yaml

I don't even understand why so much escaping is needed, but I'm glad it works.

Thanks for the tip @mikefarah!

[skreienk]

This does not work. Under some structures it will report the wrong values. It will give you all the correct keys, but the values won't always match.

[mikefarah]

Hey @skreienk this discussion is quite old, since then yq natively supports property file formats. Please see: https://mikefarah.gitbook.io/yq/usage/properties

[mikefarah]

Note: yq now supports property file formats natively, see https://mikefarah.gitbook.io/yq/usage/properties

[skreienk]

Thanks for that Mike, I hadn't found that yet. I mostly posted because google still led me to this in one of the searches I did. And thanks for all your work on yq too!