If we ran console.log(data) on a object, Node.js automatically pretty prints (formats and colourises) the output

{
    "this": {
        "is": {
            "a": {
                "nested": {
                    "object": 123456
                }
            }
        }
    }
}

However, if we were to log our data with some sort of JSON logging library (i.e bunyan)

{hostname":"ExpensivePaperweight","pid":29946,"level":30,"this":{"is":{"a":{"nested":{"object":123456}}}},"msg":"","time":"2021-12-02T04:32:16.834Z","v":0}

Not very usable to us hey…

Bunyan has a formatter!

Bunyan actually comes with a CLI formatter

node program | npx bunyan

Enter jq

https://github.com/stedolan/jq

jq is an awesome tool for exploring JSON data from within a command line; additionally it can also format lines of compact JSON, and pretty print it

./program | jq

{
  "hostname": "ExpensivePaperweight",
  "pid": 29946,
  "level": 30,
  "this": {
    "is": {
      "a": {
        "nested": {
          "object": 123456
        }
      }
    }
  },
  "msg": "",
  "time": "2021-12-02T04:32:16.834Z",
  "v": 0
}

Not all of my lines are JSON!!!

If your code has non-JSON lines (i.e. If you ran yarn start, it has overhead messages) you can use tail -n +LINE_NUMBER to skip the first LINE_NUMBER - 1 items!

i.e. If your program has two lines of arbitrary data, and lines three and onwards are JSON-formatted strings, then you can run ./program | tail -n +3 | jq

Wings

https://github.com/sharkdp/bat

For more readability, you can use a tool like bat (improved version of cat) to paginate / change colours.

$ yarn start | tail -n +3 | jq | bat -l json --paginate none

I would recommend using bat -l json or bat -l json --pager none (to not paginate)