This document provides an overview of web services including examples, common protocols, differences between XML and JSON formats, HTTP methods, jQuery AJAX methods, and suggestions for further reading on specific web service standards and technologies. It lists popular web services, describes protocols like SOAP, REST, and JSON-RPC, compares XML and JSON syntax and features, demonstrates HTTP methods and jQuery for asynchronous requests, and recommends resources on XML-RPC, WSDL, and ESBs.

1. Web Services

5. Examples:
- facebook
- sendgrid
- firebase
- google prediction api
- google QPX api
- stripe
- paypal

6. Web Services Protocols
● BEEP - Blocks Extensible Exchange Protocol
● E-Business XML
● Hessian
● JSON-RPC
● JSON-WSP
● REST - Representational State Transfer
● SOAP - outgrowth of XML-RPC, originally an acronym for Simple Object Access Protocol
● Universal Description, Discovery, and Integration (UDDI)
● Web Processing Service (WPS)
● WSFL - Web Services Flow Language (superseded by BPEL)
● WSCL - Web Services Conversation Language
● XINS Standard Calling Convention - HTTP parameters in (GET/POST/HEAD), POX out
● XLANG - XLANG-Specification (superseded by BPEL)
● XML-RPC - XML Remote Procedure Call

7. XMS vs JSON

8. <?xml version="1.0" encoding="UTF-8"?>
<bookstore>
<book category="CHILDREN">
<title>Harry Potter</title>
<author>J K. Rowling</author>
<year>2005</year>
<price>29.99</price>
</book>
<book category="WEB">
<title>Learning XML</title>
<author>Erik T. Ray</author>
<year>2003</year>
<price>39.95</price>
</book>
</bookstore>
[
{
“title”:”Harry Potter”,
“author”:”J K. Rowling”,
“category”:”CHILDREN”,
“year”:2005,
“price”:29.99
},
{
“title”:”Learning XML”,
“author”:”Erik T. Ray”,
“category”:”WEB”,
“year”:2003,
“price”:39.95
}
]

9. XML
pros
- extendable
- offers support for validation
- sometimes easier to understand by a human reader
- supported by more web services
cons
- huge overhead
JSON
pros
- easier to implement parsers
- faster parser
- smaller data
- works hand in hand with AJAX and JavaScript
cons
- limited data types
- can’t enforce rules between interfaces of services
- supported mostly by services that are over HTTP

10. var string = JSON.stringify(object);
var object = JSON.parse(string);
object.toJSON - changes the normal transformation
Example
{ "age" : 2 , “name”:”John” }

13. HTTP METHODS
GET
HEAD
POST
PUT
DELETE
TRACE
OPTIONS

15. jQuery AJAX
$.ajax({
method: "PUT",
url: "some.php",
data: { name: "John", location: "Boston" }
})
.done( function( msg ) {
alert( "Data Saved: " + msg );
} );

16. jQuery AJAX
$.get("URL")
.done(function(data){
//code on success
})
.fail(function(){
//code on fail
})
.always(function(){
// code called at every end of ajax request for both success and
failiure
});
$.post("URL",data)
.done(function(respose){
//code on success
})
.fail(function(){
//code on fail
})
.always(function(){
// code called at every end of ajax request for both success and
failiure
});

17. Further reading
- XML-RPC
- JSON-RPC
- SOAP
- WSDL (web service definition language) + SOAP binding
- ESB (Enterprise Service Bus)