Convert JSON to headed TSV

Question

Given a JSON file like this,

[
  {
    "h1": "x1",
    "h2": "x2"
  },
  {
    "h1": "y1",
    "h2": "y2"
  }
]

I extract it as a headed TSV using the following jq code. But I need to specify the header names twice. Is there a way to just specify the header names once? Thanks.

[
    "h1"
    , "h2"
], (.[] | [ 
    .h1
    , .h2
]) | @tsv

Answer 1

Here's a relatively robust jq script for printing the TSV with headers using the key names in the first object:

(.[0] | keys_unsorted) as $keys
| $keys,  (.[] | [.[$keys[]]])
| @tsv  

This of course assumes the -r command-line option.