1. A method for generating a web service providing a programming interface between a web application and a user application, the method comprising: creating and storing a script of a navigation flow of at least one transaction of the web application using at least one computing device, the navigation flow representative of an interaction between a user and a web application interface of the web application during the at least one transaction; creating and storing a text file describing a function and at least one of an input parameter or an output parameter using the at least one computing device, the function to be called by the user application for executing the at least one transaction in the script of the navigation flow; creating and storing web service interface code corresponding to a call of the function as described in the text file using the at least one computing device; and creating and storing web service implementation code for executing the interaction based on the script of the navigation flow using the at least one computing device, wherein the web service implementation code uses the web service interface code to implement the function without the user.