Yaml to Json

To convert output to json, use the --output-format=json (or -o=j) flag. You can change the json output format by using the indent flag.

Given a sample.yaml file of:

b:
  c: 2

then

yq eval -o=j sample.yaml

will output

{
  "b": {
    "c": 2
  }
}

To format the json:

yq eval -o=j -I=0 sample.yaml

will yield

{"b":{"c":2}}

Multiple matches

Each matching yaml node will be converted to json and printed out as a separate json doc. You may want to set the indent flags to 0 if you want a json doc per line.

Given a sample.yaml file of:

bob:
  c: 2
bab:
  c: 5

then

yq eval -o=j '.b*' sample.yaml

will output

{
  "c": 2
}
{
  "c": 5
}

Json to Yaml

To read in json, just pass in a json file instead of yaml, it will just work - as json is a subset of yaml. However, you will probably want to use the Style Operator or --prettyPrint/-P flag to make look more like an idiomatic yaml document. This can be done by resetting the style of all elements.

e.g given a json file

{"a":"Easy! as one two three","b":{"c":2,"d":[3,4]}}

then

yq eval -P sample.json

will output

a: Easy! as one two three
b:
  c: 2
  d:
  - 3
  - 4