Question 167925 in Json Question posted in
Our archive of expertly curated questions and answers provides insights and solutions to common problems related to this popular data interchange format. From parsing and manipulating JSON data to integrating it with various programming languages and web services, our archive has got you covered. Start exploring today and take your JSON skills to the next level

Json – Select with a string containing spaces using map_values not working as expected

I have the following dataset :

{
  "data": {
    "system": [
      {
        "login": "vault keystore password",
        "password": "123456"
      },
      {
        "login": "vault keystore masked",
        "password": "MASK-789101112"
      },
      {
        "login": "vault salt",
        "password": "toto"
      },
      {
        "login": "vault iteration",
        "password": "10"
      },
      {
        "login": "keystore Alias",
        "password": "vault"
      }
    ]
  }
}

I want to retrieve in my shell the password when login is "vault keystore password".

The closest that I have found is :
.data.system |map_values(select(.login == "vault keystore password"))[].password
but it returns me not the expected output (I wanted 123456):

"123456"
"toto"
"vault"

Could you please explain me the correct syntax ?

Tags:

3

Answers


  1. 0

    First iterare over the array, then select by criteria:

    jq -r '.data.system[] | select(.login == "vault keystore password").password'

# or by importing a string from outside dynamically

jq -r --arg login "vault keystore password" '
  .data.system[] | select(.login == $login).password
'

    123456
    Login or Signup to reply.
  2. 0

    Using just map(select(..)) will solve your problem.

    .data.system | map(select(.login == "vault keystore password"))[].password

    By the official docs, using map_values() should also work. For some reason jq (jq-1.6) is misbehaving (possibly a bug) while using for this filter. The same filter works well with gojq.

    Per builtin.jq, map_values(..) is just

    def map_values(f): .[] |= f;

    so essentially, your filter comes down to

    .data.system[] |= select(.login == "vault keystore password")

    which is producing 3 objects inside the list system, which is incorrect. On the other hand gojq handles it correctly. I would argue the whole issue is around the update assignment operator of jq (i.e. |=), which is known to have caused issues in the past. See https://github.com/stedolan/jq/issues/2051

    jq has been stuck in a release limbo for a while now (https://github.com/stedolan/jq/issues/2305). So until the time a new release > 1.6 comes along, gojq would be an ideal replacement with much of the known issues fixed (those of jq).

    On gojq version 0.12.12

    echo '{"data":{"system":[{"login":"vault keystore password","password":"123456"},{"login":"vault keystore masked","password":"MASK-789101112"},{"login":"vault salt","password":"toto"},{"login":"vault iteration","password":"10"},{"login":"keystore Alias","password":"vault"}]}}' |
  gojq '.data.system | map_values(select(.login == "vault keystore password"))[].password'

    produces

    "123456"
    Login or Signup to reply.
  3. 0

    You can do:

    .data.system | .[] |select(.login=="vault keystore password").password

    Demo

    Or as a jq command line:

    jq -r '.data.system | .[] |select(.login=="vault keystore password").password'

    Or you can use ruby:

    ruby -r json -e 'JSON.parse($<.read)["data"]["system"].
    select{|h| h["login"]=="vault keystore password"}.
    each{|h| puts h["password"]}'

    Either of those, given JSON on STDIN or as a file prints 123456 on STDOUT.

    Login or Signup to reply.
Please signup or login to give your own answer.

Back To Top
Search