Information processing system and information processing method

A wrap server executes operates as an API call receiver module that receives a unified API call from each of the one or more external systems, an API call converter module that converts an API call received by the API call receiver module into an API call corresponding to the contract information on a basis of the contract table and a user name of the user as request-source information, the request-source information being an argument of an API call received by the API call receiver module, a converted API call module that calls a Web API supplied by the central system by using the API call converted by the API call converter module, and an information return module that returns information to an external system that called the wrap server, the information being returned by an API call from the converted API call module to the central system.