Services come in 3 flavours: Domain Services, Application Services, and Infrastructure Services. Domain Services : Encapsulates business logic that doesn’t naturally fit within a domain object, and are NOT typical CRUD operations – those would belong to a Repository. Application Services : Used by external consumers to talk to your system (think Web Services). If … Read more
A Data Transfer Object is an object that is used to encapsulate data, and send it from one subsystem of an application to another. DTOs are most commonly used by the Services layer in an N-Tier application to transfer data between itself and the UI layer. The main benefit here is that it reduces the … Read more
Kent wrote an interesting blog about this topic: View Models: POCOs versus DependencyObjects. Short summary: DependencyObjects are not marked as serializable The DependencyObject class overrides and seals the Equals() and GetHashCode() methods A DependencyObject has thread affinity – it can only be accessed on the thread on which it was created I prefer the POCO … Read more
I don’t actually think that DI/IoC are that uncommon in Python. What is uncommon, however, are DI/IoC frameworks/containers. Think about it: what does a DI container do? It allows you to wire together independent components into a complete application … … at runtime. We have names for “wiring together” and “at runtime”: scripting dynamic So, … Read more
I would say, it depends on kind of dev team you are and your application needs. For example, if you require a lot of querying, that mostly means it would be more work for your developers to use Redis, where your data might be stored in variety of specialized data structures, customized for each type … Read more
Use POST. In 2010, using GET was probably an acceptable answer. But today (in 2013), browsers will pre-fetch pages they “think” you will visit next. Here is one of the StackOverflow developers talking about this issue on twitter: I’d like to thank my bank for making log off a GET request, and the Chrome team … Read more
It would be a lot nicer if javascript had namespaces built in, but I find that organizing things like Dustin Diaz describes here helps me a lot. var DED = (function() { var private_var; function private_method() { // do stuff here } return { method_1 : function() { // do stuff here }, method_2 : … Read more
Disclaimer: the following is a description of how I understand MVC-like patterns in the context of PHP-based web applications. All the external links that are used in the content are there to explain terms and concepts, and not to imply my own credibility on the subject. The first thing that I must clear up is: … Read more
The biggest use of partial classes is to make life easier for code generators / designers. Partial classes allow the generator to simply emit the code they need to emit and they do not have to deal with user edits to the file. Users are likewise free to annotate the class with new members by … Read more
Cohesion refers to what the class (or module) can do. Low cohesion would mean that the class does a great variety of actions – it is broad, unfocused on what it should do. High cohesion means that the class is focused on what it should be doing, i.e. only methods relating to the intention of … Read more