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​J​S​O​N ​Filters

JSON filters are used to manipulate JSON objects, often API responses.


json

The json filter will convert any variable to json string.

twig
{{ [1, 2, 3] | json  }}
{# results in: '[1, 2, 3]' #}

{{ true | json }}
{# results in: 'true' #}

{{ "foo" | json }}
{# results in: '"foo"' #}

jq

The jq filter apply a JQ expression to a variables. The filter always return an array of result and will be formatted as json. You can use the filter first in order to return the first (and potentially the only) result of the jq filter.

twig
{{ [1, 2, 3] | jq('.')  }}
{# results in: '[1, 2, 3]' #}

{{ [1, 2, 3] | jq('.[0]') | first }}
{# results in: '1' #}

Another example, if the current context is:

json
{
  "outputs": {
    "task1": {
      "value": 1,
      "text": "awesome1"
    },
    "task2": {
      "value": 2,
      "text": "awesome2"
    }
  }
}
twig
{{ outputs | jq('.task1.value') | first }}

the output will be 1.

Arguments

  • expression: the jq expression to apply