Formatting data with Vim

Reindent JSON

One of Vim’s great features is how it can integrate with external utilities. Here are the commands that I use most.

Prettify JSON

:% !python -mjson.tool

Will take the current buffer text and pass it to Python’s json.tool module and replace buffer with results, effectively reindenting JSON document.

Alternatively, if jq is available:

:% ! jq .

Convert pretty JSON to a compressed one-line form

:% ! jq -c .

Reindent XML

:% !xmllint --format --recover -

Pretty print Python data structures:

:% !python -c 'import pprint, sys; pprint.pprint(eval(sys.stdin.read()))'

Python data structure to JSON

:% !python -c 'import sys, json; from collections import OrderedDict; print(json.dumps(eval(sys.stdin.read()), indent=2))'

JSON to YAML

:% !python -c 'import sys, json, yaml; print(yaml.dump(json.load(sys.stdin), indent=2))'

YAML to JSON

:% !python -c 'import sys, json, yaml; print(json.dumps(yaml.safe_load(sys.stdin), indent=2))'