I'm currently working with an online application that requires multiple screens/steps in order to complete. The application domain is modeled using an object graph. Persistence to and from a database is done using an ORM package. As I progress through the screens I build up the object graph. Between screens I serialize/deserialize the o...
Hi, I have a windows application that has its business logic layer implemented as a WCF service. This service is currently hosted on IIS. I wanted to know that if there's a way where I could optionally run the application in standalone mode when a service isn't available/feasible. ...
Service provider frameworks generally there have two systems viz. OSS(Operational Support System) and BSS (Business Support System). Theses systems are separated by deployment constraint, in most of the cases one has one bss deployed per 'n' number of oss sites. While designing any such framework is it advisable to have database separat...
I have a simple problem. I have to fetch a url (about once a minute), check if there is any new content, and if there is, post it to another url. I have a working system with a cronjob every minute that basically: for link in models.Link.objects.filter(enabled=True).select_related(): # do it in two phases in case there is cross pol...
Imagine you have business domain model on server application and you are going to develop rich client application. You can use DTO to transfer data to client and changes to server or use WCF services and generate new classes on the client. Another way is to transfer the same objects as you use on server in your business logic layer. T...
I've been following a mostly DDD methodology for this project, so, like any DDD'er, I created my domain model classes first. My intention is to use these POCO's as my LINQ-to-SQL entities (yes, they're not pure POCO's, but I'm ok with that). I've started creating the database schema and external mapping XML file, but I'm running into som...
Hello, I'm interested about using 2 different classes in 2 different environment. Both classes should share the same structure (methods), but the one used in production would be "light", with less verifications or less funtionnality or different actions. Example: a SQL query class which doesn't check the type/existence of fields. Other...
I have been browsing this site for the answer but I'm still a little unsure how to plan a similar system in its datbase structure and implementation. In PHP and MySQL it would be clear that some achievements are earned immediatley (when a specialzed action is taken, in SO case: Filled out all profile fields), although I know SO updates ...
I'm setting up an application, and I'm looking into purchasing a license for SQL Server. My question is pretty simple (though may have a complicated answer...) How many users accounts do I really need, for SQL Server? The way I see it, I'd give one master administration account, maybe 2 or 3 user accounts, and then one application-base...
Suppose I would like to depict data flow between two servers in Visio. I have boxes to represent servers and arrows to represent communication / data flow. In this situation: Server A always initiates connections to Server B. Server A reads from server B, but does not write. How would this be depicted? Which way would the arrows po...
Maybe a strange question, but where would you put HttpHandler classes in a n-tier architecture? I have a service layer, a domain model layer and a data layer. Should I create a separate class library for the HttpHandlers? ...
An architect at my work recently read Yahoo!'s Exceptional Performance Best Practices guide where it says to use a far-future Expires header for resources used by a page such as JavaScript, CSS, and images. The idea is you set a Expires header for these resources years into the future so they're always cached by the browser, and whenever...
Once the problem of loading plugins is solved (in .NET through MEF in out case), the next step to solve is the communication with them. The simple way is to implement an interface and use the plugin implementation, but sometimes the plugin just needs to extend the way the application works and there may be a lot of extension points. My ...
Hi, I am in process to start developing a Blackberry application (Proof Of Concept) on the lines of SalesForce and SalesNow CRM. I am a web developer with skills on LAMP technologies with a limited knowledge in JAVA /J2ME / BB Native libraries. Have gone through all the examples / samples on RIM / STACKOVERFLOW websites. Expert advice n...
Here's a very broad question: I've been building a small MVC framework in PHP, mostly for the sake of learning better practices in my coding (and so I have a system to manage my home finances). In reading up, I've discovered a lot on VOs and DAOs, which were new to me, at least in a formalized way. This made me realize that even thoug...
I've got this Silverlight Prism application that is using MVVM. The model calls a WCF service and a list of data is returned. The ViewModel is bound to the View, so the ViewModel should have a List property. Were should I keep data returned by a WCF service in MVVM? Should the List property be calling into the Model using its gette...
I am in the process of updating a website for the third time in in 2 years, looks like this is going to happen all of the time and several websites are using the same DB. I want to use the same code for all of them and keep it easy to update in the future. So I plan on writing some interfaces and then place the business login in a serv...
Does anyone know any presentations or talks talking about the Wow architecture? Servers, programming etc... EDIT: How is this not programming related? When it's google's or facebook's architecture it is interesting enough to produce hours of video material or multiple PHD theses. I would very much like to know how the world is divided ...
We have a decent sized MVC project running well at the moment, i've started to look at some re-factoring and I have a question. At the moment the Data Layer and Service Layer is stored in a seperate class library. The controllers load the data objects (generated from linq2sql) from the service layer which does any logic check and then ...
Hi, I am facing a class resolution issue while trying to make my architecture flexible. To make it simple, consider the following example: I have four tiers: UI, BL, Common and DAL I have a base class in my BL layer as defined below: public class User { private UserDTO _d; public User() { _d = ...