Introduction & Scope#
When developing a new web service, you may need to do an initial spot test walk through the operations or try to break the service based on the permissible data type values. You could hand craft all the operations, with their respective arguments, into a handful of URLs but that would seem pretty inefficient. I found myself in a similar situation and wanted a programmatic way to walk through the service operations with a specific input data set. To be clear, I am not attempting to recreate a full web service testing application but rather a simple script to spot check responses and catch any bugs in a web service endpoint's handler.
Investigating the WSDL#
We can automatically flesh out our operations and the message data types by leveraging the endpoint's WSDL. In my case, I was specifically interested in the request/response operations available under the HTTP GET verb. We can get the parameter names and argument types by looking at the types section and then the actual operations under a WSDL binding that includes an HTTP binding element with the verb attribute value of GET.
Fortunately, I am dealing with input messages using just the built in data type schema provided by the WSDL specification. This means that no complex types are involved and the testing input domain is somewhat simplified. Also, most of the web service operations use a standard set of parameter names such that I am able to create a smaller data set of inputs based around them.
The Code#
Your modifications would be to the test_args dictionary. You can specify a wide range of different arguments to feed your operations by parameter names. The service I was testing against used many of the same parameter names and corresponding domain.
Conclusion#
Thrown together, the script provides an easy way to spot test a web service by automatically processing the WSDL for a particular binding and running those bound operations against a provided set of input messages for it.