When catering for multiple .NET Client Applications - say - Web, Desktop and then throw in an Android app (Java), placing the business logic behind some WCF REST API services can make it easier and quicker to build applications, as there is no business logic to implement client side for each technology.
(I know that there will be a point of changing the UI to cater for new business logic, but the idea is the core of the system sits behind an API, not in the client application.)
Although RavenDB serves as the Storage Mechanism...
What is the general architectural advice of using RavenDB behind SOA services? Is it just your standard IDocumentStore/IDocumentSession behind the WCF instance and go from there?
Yes, you can just use it like that.
Note that RavenDB comes with clients for both .NET and Java.
Related
I create my API rest with Django, but I don't understand how convert an API to micro services, I don't understand the real difference between these.
I see an API like a micro service, but I don't know convert an entire API in micro service, I need create micro web servers?
Please, I can't understand a micro services, and I need understand this.
A microservice exposes it's interface, what it can do, by means of an API. The API is the list of all endpoints that a microservice respond when it receives a command/query. The microservice contains the API and other internal+hidden things that it uses to respond to client's requests.
An API is all that the clients see when they look at the microservice, although the microservice is bigger than that. A microservice hides its internal structure, it's technology stack, it's database type (sql, nosql - it could be anything); a microservice could move from sql to nosql, from python to php, but keep it's API unchanged.
API - It a way of exposing functionality over web. Imagine you have developed some functionality in .Net but not you are developing some software in a different language. Would you develop the same functionality again? No. So, just expose it via web service.Web services are not tied to any one operating system or programming language. For example, an application developed in Java can communicate with the one developed in C#, Android, etc., and vice versa.
Microservice - They are used to break a complex software into small pieces of individually deployable, testable, loosely coupled sub-modules. Micro Services are designed to cope with failure and breakdowns of large applications. Since multiple unique services are communicating together, it may happen that a particular service fails, but the overall larger applications remain unaffected by the failure of a single module.
API Vs Microservice - Now that we have broken our complex software into loosely couple sub-modules. These sub-modules communicate with each other via an API. Therefore, Microservices and an API solve different problems but works together!
More Details:
The Difference between Web Services and Micro Services
RESTful API vs Microservice
a microservice is an autonomous RESTful service. It means, there is just one service on each server. In Spring Boot when you bootstrap your RESTful service, it will get an instance of tomcat(it's embedded tomcat) and run your service on it. So, if you have more than one service on a server, it is not a microservice, because these services are not autonomous.
I worked with WCF services in our projects. We implemented most of the features as services in WCF and consumed from other projects which are web applications, desktop applications. Is this what SOA is ? Now I am getting some job oppurtunities who are looking for SOA developers, I am not sure if I can claim that I implemented SOA in the applications I developed. I read about SOA but could not get to a conclusion to my question. Can anybody explain me to clear my doubts ? Thanks for your help.
Whilst studying for the Microsoft 70-513 - Microsoft .NET Framework 4 Windows Communication Foundation, the term Service Orientated Architecture (SOA) is used quite often. The Microsoft book I have read states that;
"The architectural principles behind an SOA is the ability to reuse
existing software assets wherever possible and to expose the
functionality of these assets as a set of services."
So if you have used WCF to implement services into your applications, then it would seem you have experience in working with SOA.
My understanding about Service Oriented Architecture
We write WCF services which can be consumed by application written in
various technologies Desktop, Phone or Web.So, that we don't have to
write Service layer for each technology.
Many times it happens that your core business logic remains same for
years but, your UI or Client changes form Desktop to Phone to
Browser changes so, in this case you don't have to spend time again
writing same thing.
And as name it self say that it is service oriented so, if any
application which is able to consume services your winner.
I would like to use a technology that is used for communication between services and several thousands of clients. I came to know of WCF and read a little about it. While it looks attractive and has no interoperability issues, i would like to know about other leading technologies which can give me the same features as WCF ? Are there any open source technologies out there ? Also, which is the most widely used technology? I just want this information before i commit myself to WCF.
EDIT: By alternative to WCF, i mean to say that i am looking for a framework that will help me to implement a webservice in linux or any other platform. For example, the wcf simplifies the process of creating a webservice by the use of hard coded .NET applications. Similarly, i need a tool in linux. I came across mono,but found out that it is not complete and not very reliable.
I also provide an Open Source WCF alternative in ServiceStack A modern, code-first, DTO-driven, WCF replacement web services framework encouraging code and remote best-practices for creating DRY, high-perfomance, scalable REST web services.
There's no XML config, or code-gen and your one clean C# web service is enabled all JSON, XML, SOAP, JSV, CSV, HTML endpoints are enabled out-of-the-box. It includes generic sync/async service clients providing a fast, typed, client/server communication gateway end-to-end.
I don't think there is any .net framework with comparable features. But the core protocols of WCF such as WSDL/SOAP are not Microsoft specific so it's not as if you're tying yourself into a particular protocol, you're just choosing an implementation.
To put it another way if you choose to migrate away from .net in the future then I would say the WCF migration would be one of the easiest parts. But if you stay with .net WCF is almost certainly going to be the best implementation available given the investment Microsoft has in it (Azure is built on WCF for example).
I am learning wcf but I have trouble understanding the benefits. Is there ever a time I would want to use traditional web services?
I read another thread with these benefits:
Opt in model for members using a certain attribute
Better security
No need to worry about binding (can't understand how this is true)
No need to worry about the xml
I read Programming WCF Services however this was an advanced book a bit like CLR via C#. I am now reading Learning WCF Services and will read Essential WCF (is recommended).
What would happen if I use a normal class to try to talk to a web/service reference? I know this sounds really naive, it's just my lack of experience in web services.
I am coding some WCF services so I am getting exposed to the specifics. They are interacting with a SOAP web service provided by my web host so I can get stats on my site. Is there anything wrong in this approach?
Thanks
WCF is a unified programming model for developing connected systems. What this means is that you use a single framework to develop service-oriented solutions. WCF allows you to keep your service implementation relatively unaware and care free of what's going on under the covers as far as how your service is consumed by clients and communication is handled. This allows you to take your service implementation and expose it in various ways by configuring it differently without touching your service implementation. This is the unified part. Without WCF, you have to get familiar with a framework specific for a particular communication technology such as ASP.NET asmx web service, .NET remoting, MSMQ etc and usually those frameworks impose on your service implementation and creep in such as using WebMethod attribute or having to derive from MarshallByRefObject object etc and you just can not take your service implementation and easily expose it over another communication stack. If I have a service that adds two numbers, why can it not be exposed over http or tcp easily without having to worry about low level details? This is the question in your post regarding binding. Binding allows you take a service and configure it so that it can be exposed over different transports and protocols using different encodings without ever touching your service implementation.
Is there ever a time I would want to use traditional web service?
Web service uses well defined, accepted, and used standards such as HTTP and SOAP. So if you want your service to be consumed by wide range of clients, then you would want to expose your service as a web service. WCF comes with pre-configured bindings out of the box that allows your service to be exposed as a web service easily: basicHttpBinding and wsHttpBinding. You may also want to consider RESTful services which is an architectural style that fits more natural with the HTTP model. WCF supports RESTful services as well
What would happen if I use a normal
class to try to talk to a web/service
reference? I know this sounds really
naive, it's just my lack of experience
in web services.
WCF service can expose the wsdl for a service just like ASP.NET asmx web service does. You can generate a client side proxy by simply adding a service reference to your client project. There is also a command line tool called svcutil that also generates the client side code that allows you to easily communicate with the service. The client side service class basically mirrors the service interface. You create an instance of the client side proxy for the service and then simply call methods on it just like any other .NET object. Under the covers, your method call will get converted to a message and sent over the wire to the server. On the server side, that message will get dispatched to the appropriate service method.
I hope this helps a bit.There are lots of online content such as videos on MSDN and channel 9 that you check out. The more you pound on it and expose yourself to it, the clearer WCF will get I am sure. Also, WCF is THE framework Microsoft recommends to develop connected system in .NET. The other technologies ASP.NET asmx, WSE, and .NET Remoting will most likely still be available going forward but may not be supported and developed further.
There are a number of existing approaches to building distributed applications. These include Web services, .NET Remoting, Message Queuing and COM Services. Windows Communication Foundation unifies these into a single framework for building and consuming services.
Here is a link from MSDN Why Use Windows Communication Foundation?
WCF is really the "new" standard and new generation of web service - and even more generally, communications - protocols and libraries for the .NET world.
Whenever you feel the need to have two systems talk to one another - think WCF. Whether that'll be behind the corporate firewall in your company LAN, whether it's across the internet, by means of a direct call or a delayed message queueing system - WCF is your answer. Mehmet has written a really nice summary of how WCF is the unification of a great many communication standards that existed in the Microsoft world before WCF.
I would think with the "Learning WCF" book, you should be a lot better off than with Programming WCF - that's quite advanced stuff already!
One of the mainstays of WCF is the architecture that you always talk to your service through a proxy - whether that service runs on the same machine using NetNamedPipe binding or halfway around the world in Down Under on a server - no difference, you always go through a proxy. That then also allows WCF to be so extensible - thanks to the proxy always being between the client (your application) and the service, it offers excellent ways of extending the behavior and the inner workings of WCF to your liking and needs.
WCF basically builds on SOAP communications - so interfacing and using existing SOAP services should be no problem at all. With the WCF REST Starter Kit and in the upcoming .NET 4.0 release cycle, WCF will also extend its reach into the REST style web communications, if that's ever going to be a requirement of yours.
All this really shows one of the biggest strenghts of WCF: it's a unified and extremely flexible and extensible communication framework, that can handle just about anything you throw at it. That alone is more than enough reason to learn WCF (which can be dauting at first, I agree!), and you won't regret the effort you put into this endeavor.
Marc
Have you a specific application you are writing for, or just getting your feet wet?
Google protocol buffers, is a very good choice of communications. John Skeet & Marc Gravell have both done C# implementations. See here
A .net desktop application will send information to a central server, there will be potentially thousands and thousands of deskop apps sending info to my server(s).
The data will be small in size.
Would .net web services be good for this scenerio or would WCF be better suited?
What are the pros/cons?
I'd go with a WCF REST-based service, because you'll be able to transmit pure data without the overhead of the SOAP header (and other envelope nonsense) that comes with the SOAP-based classic .asmx web service.
the possibilities for throttling, concurrency, etc. are far more developed within wcf.
its a little bit more work in the beginning, but i guess that it's better suited for scenarios where you need to have full control over your bindings.
WCF is a more robust approach to SOA. Microsoft is committed to making it the primary framework for building the next wave of Microsoft business applications. The functionality available already, early in its lifecycle, is superior to plain old web services. It's only going to get better. By going with WCF early, you will be able to ride the wave and take advantage of future new functionality.
In some cases depends on the type and amount of data to send.
WCF will give you more options to tweak your calls.
On the other hand, I can't think of advantages of implementing asp.net web services over WCF. In WCF you could also implement plain 'old' web services
ASMX is like remoting, it's still around because it shipped with 1.0, but you shouldn't use it anymore if you are starting a new project. WCF will give you many more features and better tooling support.