Google Books And Salesforce integration by REST API

Question

I am trying to integrate salesforce and google books via rest api..But it is throwing the below error -

System.JSONException: Malformed JSON: Expected '[' at the beginning of List/Set

public class GoogleBooks {

        public class Items {
        public String kind {get;set;} 
        public String id {get;set;} 
        public String etag {get;set;} 
        public String selfLink {get;set;} 

    }

}

public class GoogleBooksResponse{
    String kind;
    Integer totalItems;
    List<GoogleBooks> items; //Your existing class.
}

And in the anonymous window i am running the below -

String s;
HttpRequest req = new HttpRequest();
        req.setMethod('GET');
        req.setHeader('Content-Type','application/json');
        req.setHeader('Accept','application/json');
        req.setEndpoint('https://www.googleapis.com/books/v1/volumes?q=harry+potter');
        Http http = new Http();
        HTTPResponse res = null;
        res = http.send(req);
         s = res.getBody();
List<GoogleBooksResponse> result = (List<GoogleBooksResponse>)JSON.deserialize(s , LIST<GoogleBooksResponse>.class);

I tried running the endpoint in ARC tool which gave me a big JSON response. When i validated the JSON, it showed some error.

**https://www.googleapis.com/books/v1/volumes?q=harry+potter**

Has anyone faced this issue.

Answer 1

The response you are getting is not a list. It is an object that has a property called "items", which contains a list of Google Books. You can fix this by creating another class with the properties that you see in the result:

https://www.googleapis.com/books/v1/volumes?q=harry+potter

For example you could deserialize the result into something like:

public class GoogleBooksResponse{
    String kind;
    Integer totalItems;
    List<GoogleBooks> items; //Your existing class.
}