How can I pretty format a JSON file, with all the correct indents and everything?

Use jq a very good JSON processor and from personal preference, its the best available in the market

for just pretty print, use

jq . file_name

If you don't want to install an additional package and have python available you can do:

python -m json.tool myfile.json

It also supports reading from STDIN

Use the package yajl, Yet Another JSON Library. On CentOS 7 it is located in the base repo, and is most probably already installed on the machine.

To pretty-print a JSON file:

cat myfile.json |  json_reformat

or simply

json_reformat < myfile.json

To verify that a file is in correct JSON syntax:

json_verify < myfile.json