Jq: issue accessing keys which contain - (hyphen) in the name

[kunal-pmj]

{
"1": 4,
"2": 0,
"651": 3,
"kunal-test": 3,
"abc" : 14
}

Imagine a JSON like this.
Uisng jq ."kunal-test"

results in following error:
jq: 1 compile error
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 109 100 109 0 0 243 0 --:--:-- --:--:-- --:--:-- 244
(23) Failed writing body

[pkoppstein]

1. On a Mac or *ix machine, you would have to enclose the filter as shown in single-quotes; you’d have to perform some gymnastics if using Windows unless you put the filter in a file as explained in the online jq manual: https://stedolan.github.io/jq/manual/

2. The error message you report does not correspond at all with the other details given. In future, please follow the guidelines at https://stackoverflow.com/help/mcve as much as possible.

3. For future reference, please post usage questions at stackoverflow.com using the jq tag: https://stackoverflow.com/questions/tagged/jq

[RedactedCode]

It does seem there may be a problem with jq and hyphenated key names.
The json specification doesn't exclude hyphens in key names.

Please note the following.

jq 32-bit, Linux

jq --version

jq-1.5

jq . fragment.json

{
"pragma": "no-cache",
"server": "tsa_f",
"status": "200 OK",
"x_response_time": "438",
"x-access-level": "read-write"
}

jq .pragma fragment.json

"no-cache"

jq .x-access-level fragment.json

jq: error: access/0 is not defined at , line 1:
.x-access-level
jq: error: level/0 is not defined at , line 1:
.x-access-level
jq: 2 compile errors

jq ."x-access-level" fragment.json

jq: error: access/0 is not defined at , line 1:
.x-access-level
jq: error: level/0 is not defined at , line 1:
.x-access-level
jq: 2 compile errors

jq .["x-access-level"] fragment.json

jq: error: x/0 is not defined at , line 1:
.[x-access-level]
jq: error: access/0 is not defined at , line 1:
.[x-access-level]
jq: error: level/0 is not defined at , line 1:
.[x-access-level]
jq: 3 compile errors

jq .x_response_time fragment.json

"438"

Thus there does not seem to be any syntactical device that permits jq to correctly return values of keys that contain hyphens.

[pkoppstein]

As documented in many places, you can always use the fundamental method for accessing the value of a key: .["KEY"]

There are alternatives depending on your version of jq, but the fundamental method is supported by all versions.

[thedward]

@RedactedCode

When you type:

jq .["x-access-level"] fragment.json

the double quotes are consumed by your shell, so jq sees your expression as:

.[x-access-level]

In order to preserve the double quotes in the string passed to jq, try instead:

jq '.["x-access-level"]' fragment.json

[MaurGi]

@RedactedCode

When you type:

jq .["x-access-level"] fragment.json

the double quotes are consumed by your shell, so jq sees your expression as:

.[x-access-level]

In order to preserve the double quotes in the string passed to jq, try instead:

jq '.["x-access-level"]' fragment.json

This way does not work with variables expansion (zsh, Ubuntu 18.04) - how can we handle this case?

$ zsh --version
zsh 5.4.2 (x86_64-ubuntu-linux-gnu)
$ json='{"cloud1": {"level1": {"apps-owners": "owner1 owner2 owner3"}}}'
$ cloud=cloud1
$ level=level1

$ echo ${json} |  jq -r -c '.${cloud}.${level}.["apps-owners"]'
jq: error: syntax error, unexpected '$' (Unix shell quoting issues?) at <top-level>, line 1:
.${cloud}.${level}.["apps-owners"] 
jq: error: try .["field"] instead of .field for unusually named fields at <top-level>, line 1:
.${cloud}.${level}.["apps-owners"]
jq: 2 compile errors

$ echo ${json} |  jq -r -c ".${cloud}.${level}.[\"apps-owners\"]"  
jq: error: syntax error, unexpected '[', expecting FORMAT or QQSTRING_START (Unix shell quoting issues?) at <top-level>, line 1:
.cloud1.level1.["apps-owners"]               
jq: 1 compile error

$ echo ${json} |  jq -r -c ".${cloud}.${level}.\[\"apps-owners\"\]"
jq: error: syntax error, unexpected INVALID_CHARACTER, expecting FORMAT or QQSTRING_START (Unix shell quoting issues?) at <top-level>, line 1:
.cloud1.level1.\["apps-owners"\]               
jq: 1 compile error

$ echo ${json} |  jq -r -c '.${cloud}.${level}.["apps-owners"]'
jq: error: syntax error, unexpected '$' (Unix shell quoting issues?) at <top-level>, line 1:
.${cloud}.${level}.["apps-owners"] 
jq: error: try .["field"] instead of .field for unusually named fields at <top-level>, line 1:
.${cloud}.${level}.["apps-owners"]
jq: 2 compile errors

[nicowilliams]

@MaurGi There are command-line options for that, like --arg varname value and so on.