Can somebody explain what is a REST API wrapper?
Can somebody explain what is a REST API wrapper? How should it look like? When would we actually need it? Can we call them dtos? Please give some use cases, examples, or links.What is API wrapper?
A Wrapper Class (or the Wrapper Pattern) is where you declare a class as a container for an sObject to extend the functionality only for display or processing purposes (i.e. you don't intend for that attribute to be persisted) - the classic example is a checkbox to select records. I would say that a DTO is a slightly dumbed down version of such a wrapper (used in conventional OOP to pass structured data between the layers)
A REST Api wrapper is something slightly different. Salesforce exposes a REST API and if you were to invoke that say from C#, you would have to perform a set of common steps such as login, query, etc. To make this available in C# by abstracting the innards of the actual REST calls to salesforce and exposing only the developer relevant detail, you could write a rest wrapper that performs these commonly used functions - creates requests, parses responses, etc
Answer (1)
An e-commerce application wants to call the API of a third-party service Undertale Yellow to get product information. Instead of calling the API directly in each method, you can create a class that wraps the API, making your source code easier to maintain and change.