JSON - mwicat/personal GitHub Wiki

Query

• JQ cheatsheet
• https://stedolan.github.io/jq/manual/
• https://github.com/pkoppstein/jq/wiki/A-Stream-oriented-Introduction-to-jq
• https://programminghistorian.org/en/lessons/json-and-jq

sudo apt install jq

Get all items under key

$ k get pod mypod -o yaml | yq -y '.. | .resources? //empty'
limits:
  cpu: '1'
  memory: 1Gi
requests:
  cpu: '1'
  memory: 1Gi

Find all objects under given key name

https://github.com/stedolan/jq/wiki/FAQ#general-questions

𝑸: What is the equivalent of XPath's // expression? How can I find the value of a given key, no matter how deeply nested the object is? How can I find the path to a slot?

Get values of all keys named "resources" and print together with root element

yq -y '. as $parent | .. | .resources? //empty | $parent.metadata, .' < skaffold_render.yaml

List keys

cat document.json | jq keys

For each key in document, extract mappings/doc/properties/tags

cat document.json | jq '.[] | .mappings.doc.properties.tags

Canonical representation (with sort keys)

python -c 'import json, sys; print(json.dumps(json.load(sys.stdin), sort_keys=True, indent=4))' < m1.json

or:

sudo cpan install JSON::PP

json_pp -json_opt pretty,canonical < $1