What is API Testing?

Dynamic Linked Library (DLL) Testing

Microsoft's Component Object Model (COM) also known as ActiveX is a standard for communication between separately engineered software components (source). Any object with a COM interface can be created and used remotely:

var doc = new ActiveXObject("Word.Application");

doc.Documents.Open(wordFileName);

Using this approach, any API packaged as a COM or .NET accessible Dynamic Linked Library (DLLs) can be tested natively by Rapise.

Rapise provides support for testing the following different types of DLL API:

• Managed DLLs – written using the .NET Framework, Rapise provides special access classes for testing these APIs.

• Unmanaged DLLs – written using native Intel x86 code, Rapise provides a special DynamicWrapper than makes it easy to access these APIs

Web Service Testing

A Web service is a unit of managed code that can be remotely invoked using HTTP, that is, it can be activated using HTTP requests. So, Web Services allows you to expose the functionality of your existing code over the network. Once it is exposed on the network, other application can use the functionality of your program.

There are two broad classes of web service:

• Simple Object Access Protocol (SOAP)

• REpresentational State Transfer (REST)

Testing SOAP Web Services

SOAP web services make use of the Web Service Definition Language (WDSL) and communicate using HTTP POST requests. They are essentially a serialization of RPC object calls into XML that can then be passed to the web service. The XML passed to the SOAP web services needs to match the format specified in the WSDL.

SOAP web services are fully self-descripting, so most clients do not directly work with the SOAP XML language, but instead use a client-side proxy generator that creates client object representations of the web service (e.g. Java, .NET objects). The web service consumers interact with these language-specific representations of the SOAP web service.

Testing REST Web Services

A RESTful web API (also called a RESTful web service) is a web API implemented using HTTP and REST principles. Unlike SOAP-based web services, there is no "official" standard for RESTful web APIs. This is because REST is an architectural style, unlike SOAP, which is a protocol.

Typically REST web services expose their operations as a series of unique "resources" which correspond to a specific URL. Each of the standard HTTP methods (POST, GET, PUT and DELETE) then maps into the four basic CRUD (Create, Read, Update and Delete) operations on each resource. REST web services can use different data serialization methods (XML, JSON, RSS, etc.).

Rapise contains a built-in REST definition builder and object library that allows you to prototype out your REST web service requests, inspect the returned HTTP headers and HTTP response body and then covert into a parameterized set of Rapise objects that can be scripted against in the main Rapise JavaScript editor.