Web Notes

If you think in a generic way about all well implemented RESTful APIs you will find a pattern that can be easily described and stored in metadata. Most RESTful API is just a combination of the following elements: Resource location (URL) HTTP method Header information Input parameters (required and optional) Content type Output parameters Business logic description Today I would like to discuss an interesting problem that I came across recently. Imagine for a second that you need to implement a RESTful API client which uses a combination of metadata which describes API and a user input in order to make a HTTP calls.  In such a scenario you will quickly realize that for a subset of API calls you will need to develop a custom classes in order to have  them later serialized (to JSON or XML) in runtime so that you can send it via POST or PUT requests. This rises a question. Do I really need to implement N - 1 classes that represent all types that some API(s) expect(s) as a

A few months ago I decided to learn a big data. This sounds very complex and of course it is. All these strange names which actually tells nothing to person who is new in these area combined with different way of looking at data storage makes entire topic even more complex. However after reading N blogs and watching many, many tutorials today I finally had a chance to try to write some code. As in last week I managed to setup a Hortonworks distribution of Hadoop today I decided to connect to it from my .NET based application and this is what I will describe in this post. First things first I didn`t setup entire Hortonworks ecosystem from scratch - I`d love to but for now it`s far beyond my knowledge thus I decided to use a sandbox environment provided by Hortonworks. There are multiple different VMs available to download but in my case I`ve choose a Hyper-V. More about setting this environment up you can read here . Picture 1. Up and running sandbox environment. Now whe

In the last few days I spent some time trying to unify structure of one of the project I`m currently working on. Most of the changes were about changing variable types because it`s were not used right way. That is why in this post I want to share my observations and practices with you. First of all we need to understand what ' variable definition ' is and how it`s different from ' variable initialization '. This part should be pretty straightforward:   variable definition  consist of data type and variable name only <data_type> <variable_name> ; for example int i ; . It`s important to understand how variable definition affects your code because it behaves differently depends weather you work with value or reference types. In the case of value types after defining variable it always has default value and it`s never null value. However after defined reference type variable without initializing it has null value by default. variable initialization  is

In my two previous posts ( part 1 and part 2 ) I described both simple and more advance approach of creating Rest-full API in MVC 4. Today I want to take another step forward and go a little deeper  in the creation of API. In this post I`m going to describe how we can create asynchronous API functions which bring better performance to our applications. The first thing that need to be understand is an asynchronous operation in .NET Framework. In .NET Framework 4.0 one of the most important changed was introducing Task  class.The Tasks in System.Threading.Tasks namespace are a method of fine grained parallelism, similar to creating and using threads, but they have a few key differences and the main difference is that Tasks in .NET 4.0 don’t actually correlate to a new thread, they are executed on the new thread pool that is being shipped in .NET 4.0. More about task you can read here  but to understand this article all you need to understand about the Task<T> class is that th

Let assume that we want to create a simple scheduler which allow user to plan meeting as long as he want with 1 minute precision. There is multiple ways to make such implementation but in this post I want to present an approach I used recently. In my implementation I`ve created separated type which represents any time period. I called it Range and it`s consists of three properties (one is read-only). Main idea behind creating this time is encapsulate state and end date of used defined time period. /// <summary> /// Represents range in time. /// </summary> public class Range { /// <summary> /// Gets or sets represents range start time. /// </summary> public DateTime StartTime { get ; set ; } /// <summary> /// Gets or sets represents range end time. /// </summary> public DateTime EndTime { get ; set ; } /// <summary> /// Gets ra