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)     {         ...