Skip to main content Skip to complementary content


Talend Cloud API Tester allows you to validate the behavior of your API by creating assertions on a request. An assertion will verify a specific part of a response based on the conditions you've defined and will indicate whether or not the conditions pass.

Usage example

To make sure that your content negotiation is working. you need to know whether the Content-type header of your HTTP response is equal to the Accept header of the request.

You can do that by creating the following assertion: Header > Content-type > Equals > ${"My request"."request"."headers"."Accept"}

The last part is an expression, it allows you to grab a part of the request to check it against the response. For more information, see Using expressions.

If the received value is different from the expected value, you can click the menu to the right of the received value to copy it or to your clipboard or directly in the Expected value field.

Assertions on large numbers

Talend Cloud API Tester does not support numbers higher than 9,007,199,254,740,991. Higher numbers may be automatically modified.

Assertion results are not guaranteed when using unsupported numbers. In the example below, the number 900719925474099299111 is rounded up to 900719925474099300000.

A warning indicates that the number is rounded up.

A notification appears when a number is not supported, you can disable these notifications in API Tester settings > General.

Did this page help you?

If you find any issues with this page or its content – a typo, a missing step, or a technical error – let us know how we can improve!