Pretty Printing JSON with Ruby

If you're debugging your Ruby code, you may be used to printing out variables to the console to see what they contain, such as:

hash = {
  abc: [
    1
  ]
}
# print the variable
puts hash
# print the internal representation of the variable
p hash
# pretty-print using the `pp` gem
require 'pp'
pp hash
#
puts JSON.pretty_generate(hash)

Which would give you the following representations:

{:abc=>[1]}
{:abc=>[1]}
{:abc=>[1]}
{
  "abc": [
    1
  ]
}

However, you may not be aware of Kernel.jj which is a nice wrapper around the latter option:

hash = {
  abc: [
    1
  ]
}
jj hash

And generates a nicely pretty-printed JSON representation of our i.e. Hash:

{
  "abc": [
    1
  ]
}

This makes debugging nicer, as then we can see nice JSON representations.