Rest calls/ call outs/ webservice calls

Rest calls/ call outs/ webservice calls

AWS bucket name is placed in label and is used to fetch the Custom settings for aws credentials

AWS url is formed using root url + bucket lable + aws access key 

create a HttpRequest with endpoint, set method get or post

create Http object and pass the request.

Response gives the content (in our scenario we are getting xml files and iterating throught the nodes and storing the data in the wrapper classess and pasing the same to visual force for display)