Hi, interesting idea. I wonder if it could be modelled as another input and output format (#467)? thinking this basically is the gron "format"? example:

$ jq -n '{a:"a",b:[1]}' | gron
json = {};
json.a = "a";
json.b = [];
json.b[0] = 1;

$ jq -n '{a:"a",b:[1]}' | gron | gron -u
{
  "a": "a",
  "b": [
     1
  ]
}

I think there also has been some discussion, that i can't find now, about adding some helpers for dealing paths. That would at least simplify doing things like this a bit, for example fq has path_to_expr and expr_to_path:

$ fq -cn '".a[0]" | expr_to_path | ., path_to_expr'
["a",0]
".a[0]"

@wader, didn't know about gron, thanks for sharing.
I was thinking this would be much easier. When -p is present, the -r would be implied and the expression mentioned above would be used. Also, I just updated the issue to state that the output jsonpath format should be presentable as input.

Agree on output should be in input format, maybe should even be <path> = <value> to be valid jq? not sure what i think about -p yet, have to think about it. It would also be great with input from other jq maintainers on this but it might take a while.

@wader wrote:

It would also be great with input from other jq maintainers

The jq authors and maintainers seem to be in pretty close agreement that new command-line options are strenuously to be avoided, especially when a straightforward jq program can fill the bill.

In this particular case, the existing --stream option does seem to meet the stated functional requirements. In fact, the JSON stream produced by --stream can be used programmatically even more easily that the proposed output, the point being that the output interfaces nicely with jq's setpath.

Please also note even if the output produced by --stream -c is itself deemed unsatisfactory, it can nevertheless
very easily and succinctly be tweaked to achieve variants such as the one that has been proposed.

@wader wrote:

It would also be great with input from other jq maintainers

The jq authors and maintainers seem to be in pretty close agreement that new command-line options are strenuously to be avoided, especially when a straightforward jq program can fill the bill.

Agreed

In this particular case, the existing --stream option does seem to meet the stated functional requirements. In fact, the JSON stream produced by --stream can be used programmatically even more easily that the proposed output, the point being that the output interfaces nicely with jq's setpath.

Please also note even if the output produced by --stream -c is itself deemed unsatisfactory, it can nevertheless very easily and succinctly be tweaked to achieve variants such as the one that has been proposed.

Good point, and it's way more readable then i expected 👍

$ pbpaste | jq --stream -c 'select(length==2)'
[["Reservations",0,"Groups"],[]]
[["Reservations",0,"Instances",0,"ImageId"],"ami-a"]
[["Reservations",0,"Instances",0,"InstanceId"],"i-a"]
[["Reservations",0,"Instances",0,"InstanceType"],"t2.micro"]
[["Reservations",0,"Instances",0,"KeyName"],"ubuntu"]

...that's a step in the right direction, thanks for putting that together.

I have something that may help in my .bashrc:

#get all paths of a json
jqpath()
{
	 jq -r 'def path2text($value):
		  def tos: if type == "number" then . else tojson end;
		  reduce .[] as $segment ("";  .
		    + ($segment
		       | if type == "string" then "." + . else "[\(.)]" end))
		  + " = \($value | tos)";

		paths(scalars) as $p
		  | getpath($p) as $v
		  | $p | path2text($v)' "$@"
}
jqpath2()
{
	jq -rc 'path(..)|[.[]|tostring]|join("/")' "$@"
	#jq -r '[path(..)|map(if type=="number" then "[]" else tostring end)|join(".")|split(".[]")|join("[]")]|unique|map("."+.)|.[]' "$@"

}
#https://github.com/stedolan/jq/issues/243
#also see `gron' package to flatten json
#https://www.datafix.com.au/BASHing/2022-03-23.html