Assertions (Expect key)

Assertions in Vibranium are handled using the expect key. Even if you don't specify the expect key, Vibranium adds a default assertion to validate if the Endpoint execution is successful and that the response status code is 200.

Levels of assertions available

  • status [integer]: The expected status
  • headers [object]: Validate the response headers. The key is the response header name and the value is the expected response header value.
  • response [object]: Validate the response body. The key is the test name and value is the assertion script.
  • timing [object]: Validate the time taken by the endpoint to respond. The key refers to the timing property and value is a JS comparison


"expect": {
    "status": 200,
    "headers": {
        "content-type": "application/json"
    "response": {
        "There should be more than 10 users": "{response.length} > 10",
        "Atleast one user should be admin": "{response.all.isAdmin}.filter(isAdmin => isAdmin).length === 0",
        "All users have an ID of 32 characters": "{}.every(id => id.length === 36)"
    "timing": {
        "total": "<700",
        "firstByte": "<300"