Web services are becoming heart of SOA. The term Web services describes a standardized way of integrating Web-based applications using the XML, SOAP, WSDL and UDDI open standards over an Internet protocol backbone. XML is used to tag the data, SOAP is used to transfer the data, WSDL is used for describing the services available and UDDI is used for listing what services are available.can anyone tell that how the above are used in web services with a sample example (in java), for example how can we use xml in building of web services for SOA?
--ThankYou
Here's a good book to read:
http://www.amazon.com/Building-Web-Services-Java-Making/dp/0672326418
Download a copy of Apache CXF and look at any of the samples.
Related
I know very little about web programming but I need to establish a license generation web service to provide licenses to users of my desktop software.
I have managed to create a working & debugged SOAP service on a Win2003 server but now I have discovered that the interface that I need to provide to my payment processor must be REST.
How would you recommend I deal with this, given that I simply don't have the time to learn PHP and rewrite my web service etc. I could bypass the SOAP altogether and easily create an executable which receives the license parameters and returns an encrypted license, but it's the web interface bit that I am stuck on. I will probably subcontract someone to write a utility for this on elance, but I don't know what to ask for.
Manu thanks,
Michael
You can expose the same service as SOAP based as well as RESTful. Axis2 with WSDL 2.0 has support for this.
Please see this article RESTful Web Services with Apache Axis2 - explains things in detail..
Thanks..
There's no easy conversion from SOAP to REST. SOAP WebServices RESTful APIs use different approaches. I think it is very easy to do with Ruby on Rails (which will take care of 90% of RESTful APi for you). All you need is to implement your logic.
Sinatra example:
get '/hi' do
"Hello World!"
end
I want to use a WCF service and consume it using all the mobile platforms iPhone, android, Blackbery, Nokia etc'
Whats my best strategy for using those clients with a WCF service. it will have to be secured of course.
Thanks
amit
I disagree with SOAP and JSON. Use RESTfull service with POX (plain old xml). It will be most probably supported by all platform. Mobile phones can have limited SOAP stack implementations and JSON is usually used with browsers. My friend has BlackBerry and he continuously complains about its support for JavaScript.
To secure your service use HTTPS.
Use a SOAP or JSON endpoint. Most platforms will have support for these (or it'll be easy to find libraries). JSON is more web oriented (Javascript) but will work in other situations as well.
Mono supports WCF so maybe their iPhone and Android will support it as well.
Totally agree with #Ladislav on not expecting clients to be able to consume SOAP. Seems like SOAP stacks are lacking unless your client is native .NET or Java. Your clients will thank you by allowing them to choose JSON (web clients) or XML (system integration). Secure via HTTPS and basic auth or an API key.
If you already have an existing infrastructure of WCF services that you want to aggregate, or adapt, for downlevel clients you could put that POX (or 'REST') service in front of them and let it handle mapping protocols and formats for you. e.g. HTTP/S to TCP/IP and XML or JSON to SOAP.
The upside is that you will make it easier for downlevel clients to consume your services. The downside is that you've added an extra layer, which will cause complexity. Some tools, like WCF Routing Service (free) or Apigee (commercial), coupled with a solid automated deployment proces can help mitigate this complexity.
To build a REST service that supports XML or JSON, create your service with this template, it's designed for .NET 4.0. From there you can configure endpoints that respond in XML or JSON and let your client tell the service what response type it wants.
EDIT You can also have the service respond in a default format to reduce every client having to specify what format.
<standardEndpoints>
<webHttpEndpoint>
<standardEndpoint name="" defaultOutgoingResponseFormat="Json"/>
</webHttpEndpoint>
</standardEndpoints>
In relation to this question, I have a follow up question that I am still confused over. I have been asked to compair REST vs Web Services. From what I have learnt about REST, it is not a web service, therefore how can you compair the two? What does the question mean when it says REST in this respect?
REST is an architectural pattern for web services emphasizing the usage of URIs as resources with a small set of operations that may be performed on them (usually PUT, POST, GET, and DELETE). I'm guessing you are being asked to compare REST to the ws* standard web services which utilize a lot of other technologies (including SOAP, though SOAP itself is not a web service, it is just a protocol that happens to be used in ws* web services).
REST can be used to provide web services just like databases can be used to store names and addresses. REST is far more general purpose than simply a way of providing a web API.
REST is useful for building distributed systems. However, many people use Web Services (note the capitals, this usually denotes SOAP, WS-*) for building distributed systems.
Wow, I just saw the homework tag. That is one seriously mean question. There are industry veterans who could not come close to answering this question.
A more accurate question would be: Compare REST using HTTP versus RPC using SOAP for building distributed systems.
They probably mean REST verse SOAP. They're all web services in concept.
The abbreviation REST stands for "REpresentational State Transfer".
REST APIs are used to call resources and allow the software to communicate based on standardized principles, properties, and constraints. REST APIs operate on a simple request/response system. You can send a request using these HTTP methods.
Hence REST is just an API (an interface that allows you to build on the data and functionality of another application) architectural style.
On the other hand, web service is a network-based resource that fulfills a specific task. Yes, there's overlap between the two: all web services are APIs, but not all APIs are web services.
I have developed a small RESTful web service example using MyEclipse. I want to create a client for those WS using WSDL. How do I create a WSDL for the above web service using MyEclipse? Please help.
Take a look at this resource. It describes using WSDL 2.0 to describe a REST interface:
http://www.ibm.com/developerworks/webservices/library/ws-restwsdl/#describerestservice
WSDL ? for a REST web service ? i'd suggest you read this book for a better understanding of REST http://oreilly.com/catalog/9780596529260
You don't need WSDL (nor WADL AFAIC) documentation in rest could be plain text for developers, schemas (xsd, rdfs...etc depending on the content types you use) sitemaps for example, a lot of links and post/put templates for example ( to mimic forms in html)
I'm trying to get a handle on web services and was wondering if I get some help from the SO community. In particular, a I'm trying to get a handle on WSDL, UDDI, SOAP AND JAX-P, because I'm most familiar with Java.
Edit:
Please tell me if I'm right or wrong on these definitions:
WSDL: This is a schema to describe what kind of XML documents can be passed to and from the WS.
UDDI: This is the most confusing to me ATM and don't really have a good def.
SOAP: Basic protocol used.
JAX-p: This is used for parsing the XML documents.
As an alternative to the SOAP path you might also want to consider looking into REST-based (or RESTful) web services, for Java in particular JAX-RS: The Java API for RESTful Web Services.
That's a very broad question. At a high level, SOAP refers to the XML protocol of the messages that travel back and forth. WSDL is another XML protocol that defines the format of the SOAP messages (very useful for tools that translate SOAP requests and responses for you). Typically a SOAP service endpoint will also have a way to access the static WSDL document about that service (e.g. if a service is hosted at http://myservice.com/services/MyService, the WSDL will usually be served from http://myservice.com/services/MyService?WSDL in most implementations). UDDI is yet another XML protocol that describes queries to a registry asking for information about SOAP services stored there.
Learn SOAP and WSDL first. UDDI is not all that widely used (although getting more so slowly). JAXR is the Java API around UDDI, which means that you probably should never need to write a raw UDDI query yourself.
JAXP is just a Java XML parser API. It can be used for lots of things, not just SOAP and WSDL. Apache Axis is a good Java SOAP client tool, and wsdl4j is a good WSDL parsing tool, although Axis will also autogenerate SOAP requests and responses from Java objects for you by parsing WSDL. Optimally, you should never need to parse a WSDL document yourself, but you often have to in practice when the tool doesn't quite do what you want.
If you want a practical introduction, do the Spring Web Services tutorial: http://static.springframework.org/spring-ws/sites/1.5/reference/html/tutorial.html
Web Services messages are defined according to the WSDL schema. Some parts will define where the message is supposed to go, and some parts will define the message contents.
Good Thomas Erl introduction to whats in the WSDL
They can be embedded in SOAP messages for transmission.
UDDI is like a look up directory to find web services you might use / consume. If you're trying to tie two specific systems together as opposed to broadcast the offering of some services, its probably irrelevant to you.
In Java, you can use a web services containers like Apache Axis to comprise your web services. JaxP could be used to parse XML documents for transmission etc.
You should read some overviews from the web and then post some more specific questions :-) Maybe if you described what you were trying to achieve, some readers would have experience with similar requirements.