How to set some default values to each key in base file from other file

[msmolka]

I have following master.yaml file

root:
  - name: First
    some_value: One
  - name: Second
    some_value: Two

and update.yaml file

defaults:
  other_value: true
  one_more: Three

The expected result is:

root:
  - name: First
    some_value: One
    other_value: true
    one_more: Three
  - name: Second
    some_value: Two
    other_value: true
    one_more: Three

I tried following command:

yq eval-all '(select(fileIndex == 0).root.[] *+ select(fileIndex == 1).defaults)' './master.yaml' './update.yaml'

but the result is:

name: First
some_value: One
other_value: true
one_more: Three
name: Second
some_value: Two
other_value: true
one_more: Three

[mikefarah]

The expression you have at the moment is basically calculating A op B, and returning the result of that (e.g. 3 x 4). Whereas what you actually want to do is update each element of root with that value.

To do that, you need to:

yq eval-all '(select(fi == 0).root.[] *= select(fi == 1).defaults) | select(fi==0)' file1.yaml file2.yaml

Alternatively, you can use the new load operator which simplifies this a little:

yq '.root[] *= (load("data2.yaml") | .defaults)' data1.yaml