Skip to main content

Expressions in Mocked APIs

Legacy Documentation
You're viewing legacy documentation for API Fortress (deployed via an on-premises container). To view documentation for the new SaaS version of API Fortress — now known as Sauce Labs API Testing and Monitoring (with Sauce Connect tunnels) — see API Testing on the Sauce Labs Cloud.


The expression field in mocking can evaluate multiple fields:

Evaluate a Query

To evaluate query or post parameters use the following syntax:

request.params[parameter_name] == 'parameter_value'

Evaluate a Header

To evaluate a header use the following syntax:


Multiple Queries

You can string multiple queries together using standard Groovy expression language like below:


request.params[parameter_name] == 'parameter_value' &&
request.params[parameter_name] == 'parameter_value'



Evaluate a POST body

To evaluate a POST body use the following syntax (this only works with JSON, so content type must be set to application/json):


Evaluate the URL

You can also evaluate parts of the mocked url itself, if your mocked URL is

Starting after the ".com" you have “api”=0, “users”=1, “info”=2

Using the following syntax you can evaluate parts of the URL:


Use Wildcards

The url can use wildcards like so:\[a-zA-Z0-9\]\*

Which means the last part of the URL can be any string containing a lowercase, uppercase, or number. Then using the “request.pattern\[2\]” you can evaluate the last part.


Any manipulation needed in the expression field can be done using Groovy language.