How to format JSON file in Vim

Question

Given a file with a large JSON object all on one line like

{"versions":[{"count":2,"version":""},{"count":1,"version":"1.1.1"},{"count":14,"version":"2.9"},{...

How can I format this to be human readable in Vim?

Answer 1

Or you can install jq which is faster (written in C) from your package manager or from source and then in vim, type :

:%!jq .

Answer 2

This one-liner works well to format JSON in Vim into a human readable form:

:%!python -m json.tool

Answer 3

If PHP is available, add the tool jf as a JSON Formatter by Composer:

$ composer global require codegear/json-formatter

Then Format current file:

:%!jf %

Or add a keymap in vimrc:

nnoremap <Leader>jf :%!jf %<CR>

Answer 4

To format in a deterministic way, we need to sort the hash. None of the other answers did that for me, so I created my own:

function! FormatJson()
python << EOF
import vim
import json
try:
    buf = vim.current.buffer
    json_content = '\n'.join(buf[:])
    content = json.loads(json_content)
    sorted_content = json.dumps(content, indent=4, sort_keys=True)
    buf[:] = sorted_content.split('\n')
except Exception, e:
    print e
EOF
endfunction

Usage:

:call FormatJson()