Replacing scalar from file

[p3lim]

Let's say I have this file:

data:
  values: |
    foo: bar

And another file:

john: 42

Can I with yq replace the .data.values scalar in the first file with the contents of the second file to create this?:

data:
  values: |
    john: 42

The closest I've gotten is this:

yq ea 'select(fileIndex==0).data.values = select(fileIndex==1) | select(fileIndex==0)' first.yaml second.yaml

Which does not result in scalar data:

data:
  values:
    john: 42

[mikefarah]

Because you want to actually put the second file as string contents (rather than actual yaml) you will need to do something like this:

content=$(cat second.yaml) ./yq e  '.data.values = strenv(content)  | .data.values style= "literal"' first.yaml

Note that this will have |- and not | this means the trailing newline is _not_included :(

At the moment there is no way that I know of in the underlying go-yaml parser to get '|'

[mikefarah]

Update I worked it out! The problem is $(..) slurps trailing new lines, not go-yaml! 🤦🏼

You can do something like this:

IFS= read -rd '' output < <(cat second.yml)
output=$output ./yq e '.data.values = strenv(output)' first.yml