Entries

Similar to the same named functions in jq these functions convert to/from an object and an array of key-value pairs. This is most useful for performing operations on keys of maps.

Use with_entries(op) as a syntatic sugar for doing to_entries | op | from_entries.

to_entries Map

Given a sample.yml file of:

a: 1
b: 2

then

yq 'to_entries' sample.yml

will output

- key: a
  value: 1
- key: b
  value: 2

to_entries Array

Given a sample.yml file of:

- a
- b

then

yq 'to_entries' sample.yml

will output

- key: 0
  value: a
- key: 1
  value: b

to_entries null

Given a sample.yml file of:

null

then

yq 'to_entries' sample.yml

will output

from_entries map

Given a sample.yml file of:

a: 1
b: 2

then

yq 'to_entries | from_entries' sample.yml

will output

a: 1
b: 2

from_entries with numeric key indices

from_entries always creates a map, even for numeric keys

Given a sample.yml file of:

- a
- b

then

yq 'to_entries | from_entries' sample.yml

will output

0: a
1: b

Use with_entries to update keys

Given a sample.yml file of:

a: 1
b: 2

then

yq 'with_entries(.key |= "KEY_" + .)' sample.yml

will output

KEY_a: 1
KEY_b: 2

Use with_entries to update keys recursively

We use (.. | select(tag="map")) to find all the maps in the doc, then |= to update each one of those maps. In the update, with_entries is used.

Given a sample.yml file of:

a: 1
b:
  b_a: nested
  b_b: thing

then

yq '(.. | select(tag=="!!map")) |= with_entries(.key |= "KEY_" + .)' sample.yml

will output

KEY_a: 1
KEY_b:
  KEY_b_a: nested
  KEY_b_b: thing

Custom sort map keys

Use to_entries to convert to an array of key/value pairs, sort the array using sort/sort_by/etc, and convert it back.

Given a sample.yml file of:

a: 1
c: 3
b: 2

then

yq 'to_entries | sort_by(.key) | reverse | from_entries' sample.yml

will output

c: 3
b: 2
a: 1

Use with_entries to filter the map

Given a sample.yml file of:

a:
  b: bird
c:
  d: dog

then

yq 'with_entries(select(.value | has("b")))' sample.yml

will output

a:
  b: bird