yq/operators/path.md

Path

The path operator can be used to get the traversal paths of matching nodes in an expression. The path is returned as an array, which if traversed in order will lead to the matching node.

You can get the key/index of matching nodes by using the path operator to return the path array then piping that through .[-1] to get the last element of that array, the key.

Use setpath to set a value to the path array returned by path, and similarly delpaths for an array of path arrays.

Map path

Given a sample.yml file of:

a:
  b: cat

then

yq '.a.b | path' sample.yml

will output

- a
- b

Get map key

Given a sample.yml file of:

a:
  b: cat

then

yq '.a.b | path | .[-1]' sample.yml

will output

b

Array path

Given a sample.yml file of:

a:
  - cat
  - dog

then

yq '.a.[] | select(. == "dog") | path' sample.yml

will output

- a
- 1

Get array index

Given a sample.yml file of:

a:
  - cat
  - dog

then

yq '.a.[] | select(. == "dog") | path | .[-1]' sample.yml

will output

1

Print path and value

Given a sample.yml file of:

a:
  - cat
  - dog
  - frog

then

yq '.a[] | select(. == "*og") | [{"path":path, "value":.}]' sample.yml

will output

- path:
    - a
    - 1
  value: dog
- path:
    - a
    - 2
  value: frog

Set path

Given a sample.yml file of:

a:
  b: cat

then

yq 'setpath(["a", "b"]; "things")' sample.yml

will output

a:
  b: things

Set on empty document

Running

yq --null-input 'setpath(["a", "b"]; "things")'

will output

a:
  b: things

Set path to prune deep paths

Like pick but recursive. This uses ireduce to deeply set the selected paths into an empty object.

Given a sample.yml file of:

parentA: bob
parentB:
  child1: i am child1
  child2: i am child2
parentC:
  child1: me child1
  child2: me child2

then

yq '(.parentB.child2, .parentC.child1) as $i
  ireduce({}; setpath($i | path; $i))' sample.yml

will output

parentB:
  child2: i am child2
parentC:
  child1: me child1

Set array path

Given a sample.yml file of:

a:
  - cat
  - frog

then

yq 'setpath(["a", 0]; "things")' sample.yml

will output

a:
  - things
  - frog

Set array path empty

Running

yq --null-input 'setpath(["a", 0]; "things")'

will output

a:
  - things

Delete path

Notice delpaths takes an array of paths.

Given a sample.yml file of:

a:
  b: cat
  c: dog
  d: frog

then

yq 'delpaths([["a", "c"], ["a", "d"]])' sample.yml

will output

a:
  b: cat

Delete array path

Given a sample.yml file of:

a:
  - cat
  - frog

then

yq 'delpaths([["a", 0]])' sample.yml

will output

a:
  - frog

Delete - wrong parameter

delpaths does not work with a single path array

Given a sample.yml file of:

a:
  - cat
  - frog

then

yq 'delpaths(["a", 0])' sample.yml

will output

Error: DELPATHS: expected entry [0] to be a sequence, but its a !!str. Note that delpaths takes an array of path arrays, e.g. [["a", "b"]]