Validate JSON fields sort order

Question

I have the following JSON records stored in a container

{"memberId":123,"memberCity":"Chicago","lastTransaction":1504155600000}
{"memberId":123,"memberCity":"Chigago","lastTransaction":150175600000}
{"memberId":123,"memberCity":"New York","lastTransaction":150195600000}

I am looking to validate that the sort order in which these records are stored are sorted by memberId ASC, memberCity ASC, lastTransaction ASC

Is there a way via jq that I can assert (true/false) the sort order, taking multiple fields into account?

peak · Answer 1 · 2018-12-27T11:08:20.000

Here's a reasonably efficient solution, presented in a way that hopefully makes it easy to understand and adapt:

def sorted:
  if length <= 1 then true
  else map([.memberId, .memberCity, .lastTransaction])
  | .[0] <= .[1]
  end;

def pairs(stream):
  foreach stream as $i ([]; 
    .[-1:] + [$i]; 
    select(length==2));


all(pairs(inputs); sorted)

Invocation:

jq -n -f sorted.jq input.json

If the stars are aligned properly and you want a one-liner:

jq 'all(foreach [inputs[]] as $i ([[.[]]]; [.[-1],$i]); .[0]<=.[1])' input.json

Season to taste.

score 2 · Accepted Answer · answered Dec 27 '18 at 09:26

Any solution that requires using the -s command-line option has the drawback of requiring more memory than is needed. Similarly using sort is inadvisable in general, but if one wants a concise and simple solution, one could go with:

jq -s 'map([.memberId, .memberCity, .lastTransaction]) | . == sort'

or even in the specific case given:

jq -s 'map(.[]) | . == sort'

Validate JSON fields sort order

2 Answers2