I have been getting a bit lost in the creation of my program architecture and I want to take a step back to see if I'm approaching it correctly.
I am wondering if my setup makes sense. I'm starting to think it doesn't.
I am creating intranet applications (We were creating Internet applications, but now the scope has changed). We use an onsite Active Directory (Windows Server 2012 R2). We have a SQL Server Database.
I have been building Front End Angular applications and ASP.NET Web API's to push and pull data. I am now implementing Authentication with Auth0 and it's been a nightmare.
What kind of program architecture would you setup in this scenario?
Much Appreciated.
SQL Server + Asp.Net Web Api + Angular JS forms a perfect architecture for building Single Page Applications (SPAs). This architecture is useful for building desktop like web applications, i.e. apps that runs over web but works like desktop apps.
If you can be more specific about the problem you are facing, you will be able to get better recommendations from so.
This architecture is widely adopted in many scenarios such as SPAs. With it, you will be able to keep your front-end highly decoupled from your backend services being able to support multiple front-ends on the same set of services and run quite a few integration scenarios.
Some of the downsides of such an approach will be the extra layer of complexity added to the application (which might force you to write more tests and handle different failure scenarios that wouldn't happen otherwise, for an example) and authentication routines since you will need to authenticate two heterogeneous environments (the .NET/IIS one and the JS/Angular one).
As for the authentication pain, token-based auth schemes seem the current way to go (such as Auth0) since they let you keep and send an environment-agnostic token which will be used by different layers of your architecture.
In that sense, your architecture makes sense.
However, since you're feeling some pain in its implementation, you might want to ask yourself if you really needed all of these. When you choose an architecture, you do so trying to accomplish some specific goals (multiple front-ends? specific performance requirements? maintainability? auditability?) and the more goals you try to accommodate in your architecture the more complex will become up to a point where the pains start outweighing the benefits.
So, what were you trying to achieve in the first place?
Related
I am after recommendations for a framework (or project template) for rapid application development using C# on the back-end. It must support the following:
User login/authentication
SPA
Responsive client
Easy to understand client and server (not a steep learning curve like AngularJS)
Clean/uncluttered project structure (both client and server). Some OOTB ASP.Net project templates are very cluttered (eg the the VS2012/2013 SPA MVC/Knockout/BackBone template) - maybe I could be convinced, but just looking at a new project it puts me off instantly.
Easy DB access.
Flexibility on the client (for custom functionality eg adding maps and other UI libraries like D3) - don't want a client framework that you have to wrangle to paint outside the lines.
Would appreciate any/all suggestions/opinions.
Thanks
Tim
Like anything in software, there are so many ways to do this. You are essentially asking for a complete system architecture. You could try to be more specific, but your question is going gather opinionated answers and this will probably end up getting closed.
But I'm bored and will throwin a couple of pennies before that happens:
C# most likely means you'll be going .NET on IIS (though maybe its docker on linux?? refer back to my first line above)
User login/authentication
If its IIS, you could be running Windows Auth, or if in an enterprise, Kerberos or Federation. Or if its going against social sites, maybe OAuth? This one depends on what authentication your users need and is really separate of the other areas below.
SPA / Responsive client / Easy to understand...
You listed some very popular frameworks (Angular/Knockout) used in modern SPAs. You may not like them but these are becoming industry standards. Responsive web is pretty much bootstrap or foundation. Though, angular material seems to be gaining popularity too.
Easy DB access.
Whats your definition of easy? Looking for an ORM? If so, Entity Framework is popular in .net apps. Or if you are more of an SQL person, maybe LINQ is easier. Many options here too.
Flexibility on the client ...
Though you may not like some of them, using popular frameworks means you get a lot of developer support behind it - and a lot more answers here on SO if you have problems. One man's sunset is another man's sunrise. What you consider difficult might be viewed as easy by another. Hard to say whats most flexible but going popular means you got more help.
I'm the custodian of a pretty sophisticated, yet antiquated, ASP.NET application. It is essentially a platform that makes creating database applications easier - with tools to read in database schemas, auto generate forms, reports, charts, and provide extremely extensive tools to manipulate those things within the UI. There are some pretty big clients using the platform for some niche applications, and despite the age of much of the code (some of it written as early as 2001), everything runs pretty well.
The company is doing well enough that i need to start considering a new version, and rather than plastering on some new features, i'd like to consider a fresh start. The current solution is a ridiculous 150 projects - down from about 220 when i first started working on this full time.
Does anyone have any tips or suggestions for the general structure of an enterprise(ish) level application? What new technologies should i consider? Maybe some particular books or websites i should review?
I've got a good handle on all of the specifics that make our platform so flexible - but because i've been locked into the general structure of our code for so long, i feel like i'm way out of touch with how the entire thing needs to be structured on a large scale. The current application still has a bunch of .NET Remoting for communication with the databases (just a tad out of date), and a ton of incredibly inefficient code written by someone who wasn't really a programmer.
WCF to serve info from the data access layer? WIF to authenticate? I'd really like to be able to assemble an API that my business partners can use to connect to the data and use a huge collection of common functions i've got set up - ideally that API could run in a web context or in some other environment.
I know this is a pretty big question that could have a lot of possible answers - just looking for some thoughts on where to really spend our research time.
Thanks!
-RP
If you want to rid yourself of all the authentication / authorization hassles, absolutely go for claims-based applications, WIF, ADFS etc.
That's the Microsoft direction - CMS, SP. Office 365. Windows Azure AD etc. are all now claims-based.
Only problem is that ADFS authenticates against AD. Have a look at Identity Server for something DB related.
Plus ADFS via ACS provides Facebook, Google etc. logons.
My company has a fairly old fat client application written in Delphi. We are very interested in replacing it with a shiny new web application. This will make maintenance a breeze and many clients want a web application.
The application is extremely rich in domain knowledge, some of which is out of our control. Our clients use the program to manage their own clients and report them to the government. So an inaccurate program is a pretty big thing. The old program has no tests. We are not sure yet if we will implement automated testing with the new one.
We first planned to basically start from scratch. But we are short handed and wanting to basically get everyone on the web as soon as possible. So instead of starting from scratch we've decided to try to make use of the legacy fat-client database.
The database is SQL Server and can be used in SQL Server 2008 easily. It is very rich in stored procedures, functions, a few triggers, and lots of tables with over 80 columns... But it is decently normalized. We want for both the web application and fat client to be capable of using the same database. This is so that if something breaks badly in the web application, our clients can still use the fat client and connect to our servers. After the web application is considered "stable", we'd deprecate the fat client.
Has anyone else done this? What tips can you give? We want to, after getting everyone on the website, to slowly change the database structure to take care of some design deficiencies. What is the best way to keep this in a data access layer so that later changes are easy?
And what about actually making the screens? Is there any way easier than just rewriting an 80 field form in ASP.Net? Are there any tools that can make this easier?
The current plan is to use ASP.Net WebForms (.Net 3.5). I'd really like to use MVC, but no one on the team knows it including me.
We are not sure yet if we will implement automated testing with the
new one.
Implement automated testing. What's the point in replacing one buggy program with another?
Good question, but "Slowly change" the db structure after getting everyone on the website, sounds like a joke...
I would rather take the opportunity to create a fresh db structure, write a bulletproof migration script for you db, that you can try out and rewrite a zillion times without any side effect fro your clients, and then write whaterver you want (fat/web) on the new db, have it tested and migrate everyone when it's ready.
I have a couple suggestions:
1) create a service layer to abstract away the dependance on the DAL. In a situation as you describe having a layer of indirection for the UI and BLL to rely on makes DB changes much safer.
2) Create automated tests (both unit and integration), especially if you plan on making fairly significant changes to the Domain or Persistance layers (BLL/DAL). To make this really easy you should always try to program to an interface. This makes your code more flexible as well as letting you use mocking frameworks (Moq is one I like) to ensure your tests truely are unit tests and not integration tests.
3) Take a look at DDD (http://domaindrivendesign.org/) as it seems to fit pretty well with the given scenario. At the very least there are some very useful patterns that can help make your application more flexible.
4) MVC isnt very hard to learn at all, it is however an easy way to get unit testing setup for the UI as a result of the MVC architecture (testing the controller and not the view). That said, there is no reason you couldn't unit test web forms, its just a bit more work. MVC really is just a UI framework/design pattern (more Model2 but we can ignore that for now). It gets you closer to the metal so to speak as you will be writting a lot more HTML and using a Model (the 'M') for passing data around.
For DDD take a look at Eric Evans book: http://www.amazon.com/Domain-Driven-Design-Tackling-Complexity-Software/dp/0321125215/ref=sr_1_1?s=books&ie=UTF8&qid=1317333430&sr=1-1
Hope that helps
ASP.NEt forms is a no starter, is completely inappropriate for something like this. I recommend to start with something like Creating an OData API for StackOverflow including XML and JSON in 30 minutes, then build your Web app on top of that (ie. push it to the client, use JQuery/Silverlight).
Let me start off by stating that I am a novice developer, so please excuse the elementary nature of my question(s).
I am currently working on a Flex Application, and am getting more and more confused about when to use server side scripting, and when to develop web services. For most of the functionality I am working on, I am taking various files from the user (client), uploading to the server for processing/conversion, then sending back to client in new format.
I am accomplishing most of this using asp.net generic handlers (ashx) files, but not very confident this is best practice. But at the same time, does making web services make any more sense? What would be considered best practice for this? Any suggestions would be greatly appreciated.
The way I look at it is as follows:
Web Services mean Established Best Practice.
For most of our development, we don't need to create "Web Services", or what I'm thinking when I think REST, SOAP, and the Twitter API. You only need to start doing that once you've got something you're going to be using every day for years.
Clean and DRY code will Lead you to Creating a Web Service
If you spend the time to clearly define the parts of your upload-process-render Architecture, and you find that it can be applied to almost everything you are doing, then all you need to do to make it a Web Service is define a clear, 1-2-3 set of rules for using the system (GET/POST data, etc.). As long as you are consciously building an architecture the whole way, you'll end up creating a Web Service if it's worthy. Otherwise there's no need.
It sounds like you have a clear workflow going, I don't know anything about asp.net though.
As far as it being confusing sometimes, and best practices, I suggest the following:
Create a Flex Library Project for your "generic ashx file handling" Flex classes. Give it a cool, simple name.
Create a .NET Library Project that encapsulates all the logic for your server-side file processing. Host it online and make it open source. I recommend github. Test it as you go, and document it, its purpose and the theory behind it.
If you don't have to do anymore work at this point, and it's just plug and chug, then you've probably arrived at something that might become a Web Service, though that's probably a few years down the road.
I don't think you should try to create a Web Service right off the bat. Just make some clean and reusable code, make a few examples, get it online and open source, have others contribute and give feedback, and if it solves a specific problem, then make it a web service. You can just use REST for now probably, and build your system around that. RestfulX is a great library for that.
Best,
Lance
making web services without any sense make no sense ;)
Now in the world of FLEX as3 with flash version 10, you can easily read local files, modify them with whatever modifcation algorithm and save local files without pinging server.
You only have to use webservices if you want to get some server data or to send some data to server. that's all.
RSTanvir
Flash / Flex uses a simple HTTP POST approach for file uploads, so trying to do that using SOAP web services will be problematic. Your approach of using ASHX here sounds reasonable to me.
To send / receive data that isn't file based (e.g. a list of files the user has uploaded previously), I would recommend looking at the open source Fluorine FX library. Fluorine uses AMF which is a highly performant way of doing data transfer with Flash. It's also purely configuration-based, which means you don't need to code against any of its APIs, just configure Fluorine to expose your .NET service classes. You could easily add attributes to those same classes to expose them as SOAP web services via WCF if you need that in the future. I would not recommend using SOAP with Flex however, due to the performance losses and also because the Flex implementation of SOAP has a history of bugs and interoperability problems.
I have a few projects coming up that have a number of endpoints or clients that can hit the same data. For instance a site might have...
A asp.net MVC based end user facing website
A web based adminitration back end that can allow specific, limited updates from some users in situatiosn where a full client isn't useful (mobile web etc)
A full on rich client for administration so we can use touch and other techniques to really make the user experience for content management shine - these may be silverlight or full on WPF apps, as needed
The question is... whats the best way to connect all that? Right now I use a multiple project split for the MVC.
ProjectName.Core - this project has all the common models, all the repository classes and all the helper classes
ProjectName.Web - an MVC project that references the Core to pull in the repositories and models it needs
ProjectName.Admin.Web - another MVC project dedicated to the admin interface that references the Core to pull in the repositories and models it needs
(which will ultimately live on a seperate subdomain from the end user facing site)
Then the story peters out int he sense of clear guidance. When the time comes to build a WPF / Silverlight project to hit the data I can do one of the following to the best of my understanding now...
Convert the "Core" to provide a RIA style DomainService, and attempt to alter the MVC projects to make use of it. However there is little guidance on using MVC with RIA, RIA is in its infancy AND the WPF to RIA story is also still only thinly documented
Do the same as above, but using WCF. However WCF prings with it async complexity that I really want RIA to hide for me.
Fall back 20 yards and just bolt plain old web services onto the Core on top of the Repositories and Models I already have. This seems... old school :)
Any thoughs and input are welcome including pointers to examples and documentation. I want to make the best decisions I can now, and am coming up to speed fast on RIA and WCF so I can but community input is always helpful.
Thanks!
Take a look at ADO.NET Data Services (formerly known as Project “Astoria”).
On my way to work today I was listening to a .NET Rocks! podcast, "Stephen Forte on Data Access Options", and they very excited about this, especially for scenarios like the one you describe.
It's interesting stuff, and something I would check out sometime very soon.
I think there's something to be said about plain old WCF services, these can make use of your domain services and repositories and expose a model more appropriate for services. Too often I've found that simply exposing the domain model on the wire ends up with a duplication of logic on both the client and the server.
My advice would be for some sort of service layer, this has the logic of shaping your domain model into appropriate types for the wire. \
Ideally I'd like to be able to share my Domain Services between the client (WPF / Silverlight) and the server (ASP.NET MVC) and have different underlaying repositories (Linq to NHibernate / Astoria). Difficult with the asynchonous nature of Silverlight.
For the curious, it certainly looks like RIA Services is the win here. Build a single DomainService then consume it everywhere. Brad Abrams covers a lot of this ground at bit.ly/94fFx - it really helped.