Have you ever needed to format some gnarly JSON that is unreadable and/or too large to look through? It’s super easy to format it with vim. We can use the popular jq tool - link at the end of this blog post.

Simple Steps to format JSON in VIM

Here is an example with a file called hello.json.

  • Open a file vim hello.json
  • Open the file in VIM vim hello.json
  • We can format with the command :%!jq . -
  • Save the file :wq

Explanation

All we need is the command :%!jq . -. Let’s break this command down.

  • : is to run a command
  • % will operatate on the entire file.
  • ! will execute an external command
  • jq . is the external command
  • - is the contents of the buffer

Note that we use %. We could instead do a visual selection using '<,'>, or select lines in the file. In the video we use the command jq "." -, which is the same thing as jq . - it’s just a little more simple to not type the extra quotes.

Below is a video in YouTube showing how it’s done.

Here are some links to both vim and jq. Note, I use Neovim these days for a number of reasons, but any VIM will work.

Side Note

We can use VIM and any external tool to format other types of files. I hope to post soon on how to format XML using the xmllint tool which can be done very easily by what is taught in this blog post.