Gunnar Peipman - Programming Blog

After working again on codebase where Entity Framework Core was used through repository and unit of work patterns I decided to write eye-opener post for next (and maybe even current and previous) generations about what Entity Framework has to offer in the light of these to patterns. In many cases we don’t have to move away from database context approach but stick with it even more than we first planned. Here’s how many useless repositories and units of work born and here’s also how to avoid these and go with implementations offered by Entity Framework Core.

ASP.NET Visual Studio

Building gRPC service on ASP.NET Core

November 10, 2019 Gunnar Peipman 135 Views 2 Comments

ASP.NET Core supports gRPC protocol that is about to replace legacy SOAP services with more performant and powerful protocol that is easier to use and support. This blog post shows how to build gRPC service and client on Visual Studio and ASP.NET Core.

Architecture/Design/Patterns ASP.NET

Using composite command in ASP.NET Core

November 7, 2019November 10, 2019 Gunnar Peipman 195 Views 2 Comments

My introduction to composite command pattern was more theoretical and focused to high-level details. This blog post focuses on implementation details and introduces how to use composite command in ASP.NET Core to upload and process photos.

Blazor

Data annotations object graph validation is coming to Blazor

November 6, 2019November 10, 2019 Gunnar Peipman 260 Views 0 Comments

Future versions of Blazor will support cascading data annotations support meaning that validation of child components is also supported. First experimental bits were released counted hours ago with .NET Core 3.1 Preview 2. Here’s how object graph validation will work in Blazor.

ASP.NET Blazor IoT Visual Studio Windows

Building Blazor “Hello, Blinky” IoT application

November 3, 2019November 4, 2019 Gunnar Peipman 769 Views 1 Comment

I thought first my ASP.NET Core edition of Hello, Blinky will be my last Hello, Blinky for long time. But then something reminded me of Blazor and I thought why not build Blazor edition of Hello, Blinky for Windows IoT Core and Raspberry Pi? After some hacking I made it work. Here’s my Hello, Blinky for Blazor.

ASP.NET

File uploads in ASP.NET Core

October 31, 2019November 10, 2019 Gunnar Peipman 1011 Views 6 Comments

Just wrote down something I had to went through with students in one of my classes – making file upload work in ASP.NET Core application. Here are samples of single and multiple file uploads using simple controller actions.

Architecture/Design/Patterns

Composite command pattern

October 26, 2019November 10, 2019 Gunnar Peipman 608 Views 2 Comments

I have previously blogged about command pattern and composite pattern. I had some projects where I succesfully mixed these two together to compose a composite command. It’s a construct to have a commands hierarchy we can execute with one shot.

Blazor

Blazor pages get partial class support

October 16, 2019November 10, 2019 Gunnar Peipman 1372 Views 2 Comments

Next .NET Core version 3.1 brings some good news to Blazor – partial page classes. Maybe it’s not so big thing for many guys out there but sure great feature for those who like clean solutions. Here’s my story about partial page classes and their comparison with code-behind classes supported already today.

ASP.NET Visual Studio

How to make ASP.NET Core compile modified views

October 13, 2019November 10, 2019 Gunnar Peipman 1533 Views 4 Comments

ASP.NET Core 3.0 applications doesn’t build views automatically by default when changes are made. Views are built when application compiles and this is expected final state for views. It’s still possible to make ASP.NET Core application build views when changes are made. Most popular case is when application is running on Visual Studio and we are working on cosmetics of view.

ASP.NET Azure Visual Studio

Publishing ASP.NET Core 3.0 application as self-contained executable to Azure App Service

October 11, 2019November 10, 2019 Gunnar Peipman 1440 Views 0 Comments

With Visual Studio 2019 we can publish ASP.NET Core 3.0 applications as self-contained executable. It’s specially useful for environments where ASP.NET Core 3.0 is not installed or where we don’t have permissions to install it. Here’s how to do it.

.NET ASP.NET Azure

Generalize file access for ASP.NET Core applications using IFileClient implementations

October 6, 2019November 10, 2019 Gunnar Peipman 1745 Views 3 Comments

Once upon a time I worked out simple file client generalization so my applications can keep files on local machine or somewhere on the cloud without changes in application code. This blog post shows how to generalize file access in web applications and provides implementations for local and cloud file clients.

ASP.NET Azure Visual Studio

Hosting web application on Azure

October 2, 2019November 12, 2019 Gunnar Peipman 1711 Views 1 Comment

Coming to cloud with web application can be scary if it’s the first time you do it. Azure cloud is not anymore about dozen of services – it’s real monster offering more than we are able to know and learn. It’s not easy to predict what will be the final path on cloud but it is possible to tell how to get started. Here’s my advice to you.

Blazor

What’s next for client-side Blazor

October 2, 2019November 10, 2019 Gunnar Peipman 1698 Views 3 Comments

.NET Conf 2019 was full of great news and interesting pieces of information for those who love .NET world like me. It was specially interesting for me to watch presentation The Future of Blazor on the Client by Dan Roth who introduced on-going work with Blazor and plans for near future. Here’s my short overview with explanations about what’s going on.

.NET C#

All about IDisposable

September 25, 2019December 18, 2019 Gunnar Peipman 1664 Views 8 Comments

So, what is IDisposable and what is disposing of objects? This is something I teach to developers classes before they are going to their first school practice at some company. One of important concepts is disposing. Here’s my story about it.

.NET

How many .NET Core SDK-s you REALLY have?

September 19, 2019December 7, 2019 Gunnar Peipman 1839 Views 1 Comment

Do you have lightweight laptop with not very big laptop where you run Visual Studio? Do you need sometimes more space? You can make some free space if you remove .NET Core versions installed over time by updates and previews. Here’s how to do it.

Using Roslyn to build object to object mapper

September 18, 2019 Gunnar Peipman 2047 Views 3 Comments

Back in time I wrote series of posts about how I built simple object to object mapper. It was nine years ago and from them more things have changed. Today I added one new implementation of mapper and this one is using Roslyn compiler services to generate dynamic code for mappings.

ASP.NET Data platform

NHibernate on ASP.NET Core

September 5, 2019September 21, 2019 Gunnar Peipman 4759 Views 22 Comments

NHibernate has been my favorite ORM for long time. Although it’s more complex for beginners than Entity Framework it’s more matured and many developers consider it to be practially an industry standard. NHibernate works with ASP.NET Core too. This blog post shows how to use NHibernate in ASP.NET Core MVC applications.

ASP.NET Azure

Create thumbnails using Azure Cognitive Services

September 4, 2019December 11, 2019 Gunnar Peipman 1080 Views 2 Comments

Azure Cognitive Services is set of powerful and intelligent cloud services to analyze photos and images. This blog post shows how to create smart thumbnails using Azure cognitive services and ASP.NET Core.

Azure Data platform

Visualize Azure CDN metrics with Grafana

August 20, 2019August 31, 2019 Gunnar Peipman 1092 Views 0 Comments

Azure CDN is one of Azure services that doesn’t provide charts and metrics in service overview page. For me these charts are important because they help me to optimize delivery of my blog artifacts. This blog post describes how I visualize Azure CDN diagnostics logs using InfluxDB, Grafana and simple data collector.

ASP.NET

System memory health check for ASP.NET Core

August 16, 2019November 10, 2019 Gunnar Peipman 1761 Views 0 Comments

I found temporary cross-platform solution for .NET Core to read system memory metrics until framework level libraries appear. This blog post shows how to build ASP.NET Core health check for system memory metrics.

.NET Linux Windows

Reading Windows and Linux memory metrics with .NET Core

August 15, 2019August 16, 2019 Gunnar Peipman 1479 Views 5 Comments

Until .NET Core gets its own cross-platform system metrics support I needed something simple to get system memory metrics of servers where ASP.NET Core application is running. I wasn’t able to find a nice solution but I still worked out something to get system memory metrics with .NET Core on Windows and Linux.