Question: Is there a way to rename keys?

[desimaniac]

Hi. Had a question.

Say you have a sample.yaml file with :

b:
  c: cat
  d: dog

Could you rename b to y?

y:
  c: cat
  d: dog

[mikefarah]

hmm not atm :(

Even if you use multiple commands, the 'write' command will put the value in as a string

[ipfaffy]

+1 was just looking for a way to do this. Would be a great addition.

[ideasasylum]

fwiw, I did this by reading the keys I want to rename into a tmp file, prefixing them with the new key name, deleting the old keys, and then merging the new keys with the everything-but-old-keys.

In Ruby it looks like this (with some parameterisation)

# Extract the old keys we want to move
`yq r #{filename} en.#{old_key} > en.extract.yml`
# Prefix the extracted keys with the new key
`yq p en.extract.yml en.#{new_key} > en.prefixed.yml`
# Delete the old keys
`yq d config/locales/en.yml en.#{old_key} > en.deleted.yml`
# Merge the new keys into the file without the old keys
`yq m en.deleted.yml en.prefixed.yml > #{filename}`

[mikefarah]

This is now possible in v4 of yq, create a new object with the desired key, merge it into the existing object, then delete the old key.

[mfulgo]

I landed on this issue while trying to figure out how to prefix keys in v4. Just adding it as a comment here in case anyone else lands here with the same issue.

a:
  b:
    c: charlie
    d: delta
e: other

yq 'with(.a.b; with_entries(.key |= "prefix_" + .))' $FILE

Should produce

a:
  b:
    prefix_c: charlie
    prefix_d: delta
e: other

[LarsBingBong]

@mfulgo you saved my day - thanks! Now I just need to dive into exactly what's going on in that cmd. If you care and have 5 - I would love you to give it some words 🙇🏿

[mikefarah]

Update:

Upon closer inspection the example above isn't quite right. It's not assigning the with_entries result to anything. Not sure how it was working before - probably a bug 😓

It should be either:

yq '.nested |= with_entries(.key |= "KEY_" + .)' data1.yaml

or; if you need to use with:

yq 'with(.nested; . |= with_entries(.key |= "KEY_" + .))' data1.yaml

This also follows with what I documented for with: https://mikefarah.gitbook.io/yq/operators/with