Web Notes

In today post I want to describe how to optimize usage of a ADO.NET SqlDataReader class by using multi-threading. To present that lets me introduce a problem that I will try to solve.  Scenario : In a project we decided to move all data from a multiple databases to one data warehouse. It will be a good few terabytes of data or even more. Data transfer will be done by using a custom importer program. Problem : After implementing a database agnostic logic of generating and executing a query I realized that I can retrieve data from source databases faster that I can upload them to big data store through HTTP client -importer program. In other words, data reader is capable of reading data faster then I can process it an upload to my big data lake. Solution : As a solution for solving this problem I would like to propose one of a multi-thread design pattern called Producer/Consumer . In general this pattern consists of a two main classes where: Producer class is res...

Today I want to cover a very common scenario about how to create a HTTP client for a WebAPI 2 service. To present my implementation I will be using one of a Task<T> extension method that I described recently on my blog. Let`s start from defining an API service. In this example it udes a REST based WebApi service with the following implementation.   [ AllowAnonymous ]     public   class   CityController    {         ///   <summary>         ///  The city repository.         ///   </summary>         private   readonly   ICityRepository  cityRepository;         ///   <summary>         ///  Initializes a new instance of the  ...

This was a very long break since I posted my last web note however it`s time to share some fresh experience with the developer community. Today I want to show one of a handy solution which allowed me to simplify a Task chaining in .NET 4.5.1. Let`s start from defining a problem which in this case is a Task.ContinueWith<TResult>  method and the way how it`s designed for a tasks chaining. So if you want to use a chaining by using this function, all the time you need to access a parent task result property which in many cases causes a lot of redundancy in the code. To demonstrate this I use a simple async WebApi2 GET cities  auto-complete function which will query a database and later map result set of entities to collection of data transfer objects (DTO). // !!BADLY DESIGNED CODE!! [ HttpGet ] public   async   Task < HttpResponseMessage > Get( string  query)     {         ...

Automated coded UI testing become very popular in the past few years. Its allow developers to create tests which are executed directly on UI level and simulate user actions. At the same time HTML5 become a standard for creating universal modern applications which can be hosts in a native browser controls. New model of creating applications brings a new challenges in the testing fields that's why in this post I want to present my solution (it takes me almost two days to get this working!) which is first step in the process of creation an end-to-end test automation for mobile applications. My solution is prototype of a .NET console application which can be use to control Android emulator and simulate user standard operation like installing app, typing and rotating. This prototype can be use as ' emulator manager ' which controls device emulator on which tests are performed - for example by using   Selenium . As initial requirements to run the project: 1) Install the ...