JQ Filtering

JQ lets you filter and transform JSON responses inline — both for display (jq_filter) and for validation (assert).

Response Filtering

Use jq_filter to transform what gets displayed:

yapi: v1
url: https://api.example.com/users
method: GET
jq_filter: '[.[] | {name, email}] | sort_by(.name)'

This filters the response before printing, so you only see what matters.

JQ in Assertions

Assertions are JQ expressions that must evaluate to true:

expect:
  assert:
    - .id != null
    - . | length > 0
    - .data | type == "object"
    - .[0].name | startswith("A")

Common Patterns

Check array length

assert:
  - . | length > 0
  - .items | length == 10

Check type

assert:
  - . | type == "array"
  - .data | type == "object"
  - .count | type == "number"

String operations

assert:
  - .name | startswith("test_")
  - .email | endswith("@example.com")
  - .url | contains("api")

Check all items in array

assert:
  - .[] | .status == "active"     # Every item matches
  - [.[] | .score > 0] | all      # All scores positive

Select specific fields

jq_filter: '{id, name, email}'         # Single object
jq_filter: '[.[] | {id, name}]'        # Array of objects

Sort and limit

jq_filter: 'sort_by(.created_at) | reverse | .[:5]'

JQ with yapi send

Apply JQ filters on the command line:

yapi send https://api.example.com/users --jq '.[0].name'

See Also

• yapi docs assert — Assertions on status, body, and headers
• yapi docs send — Quick one-off requests with --jq flag