All posts in .net

I was writing some code into To-Do.Studio so that when people demo their code and features, I have a better idea of what it is I am seeing – more specifically, what version number would I see (to understand branches and commits)…

My initial thought was : on startup i will launch git and try to get some information about branch and commit hash and then incorporate that into the configuration system and then show that in the footer…

Well, that sounded complicated and so it probably was… after a few seconds, I found this great Nuget called GitInfo that basically creates a partial class at build time that can be referred to in code,  my startup code now looks like this :

public string GitVersion
{
    get => string.Format($"V{ThisAssembly.Git.BaseVersion.Major}.{ThisAssembly.Git.BaseVersion.Minor}.{ThisAssembly.Git.BaseVersion.Patch} T={ThisAssembly.Git.Tag} {ThisAssembly.Git.Branch}[{ThisAssembly.Git.Commit}] {{0}}", ThisAssembly.Git.IsDirty?"Dirty":"");
}
...
Configure()
{
    ...
    Configuration["GitVersion"] = GitVersion;
    ...
}

While working on the backend for To-Do.Studio, we ran into a scenario where we needed to test on a developer’s machine with https (ssl) enabled.

note – we use Kestral for testing and not IISExpress.

First thing we did was to try and add a https url in the LaunchSettings.json file. That didn’t work 🙂

What we found was that had to configure Kestral manually and tell it which certificate to use. The code in our Program class looks like this :

public static IWebHost BuildWebHost(string[] args) =>
   WebHost.CreateDefaultBuilder(args)
     .UseApplicationInsights()
     .UseAzureAppServices()
#if DEBUG
     .UseKestrel(t => {
        t.Listen(IPAddress.Loopback, 55172);
        t.Listen(IPAddress.Loopback, 55000, o =>
        {
            o.UseHttps("localhostCertificate.pfx", "password");
        });
     })
#endif
    .UseStartup<Startup>()
    .Build();

But how do we get a certificate ? There are various ways but i didn’t feel like finding my win32 sdk as some instruction’s on the web… so i decided to use my Ubuntu WSL…

Two commands

erik@ErikLAPTOP:~$ openssl req -x509 -days 10000 -newkey rsa:2048 -keyout cert.pem -out cert.pem
erik@ErikLAPTOP:~$openssl pkcs12 -export -in cert.pem -inkey cert.pem -out cert.pfx

and i had a good looking self made certificate. The hardest part was to copy this cert.pfx file to a Windows directory so i could use it my code.

Voilà ! after modifying my LaunchSettings.json, i could test in either http or https mode !

"ToDoStudio.Server_http": {
 "commandName": "Project",
 "launchBrowser": true,
 "environmentVariables": {
 "ASPNETCORE_ENVIRONMENT": "Development"
 },
 "applicationUrl": "http://localhost:55172/"
 },
 "ToDoStudio.Server_https": {
 "commandName": "Project",
 "launchBrowser": true,
 "environmentVariables": {
 "ASPNETCORE_ENVIRONMENT": "Development"
 },
 "applicationUrl": "https://localhost:55000/"
 }

Basics

1. Attach a debugger to a program and hit breakpoints. When you hit a breakpoint, the debugger can show you your source code because the symbols have a mapping from the assembly code to the source code. At a breakpoint you can inspect variables, change their values. You can control the flow of execution of your program by executing the next instructions and even change what the next instruction is.
2. This technique is a bit more brute force, but consists of using logging to get insight into code which is hard to debug with breakpoints. Although less efficient than breakpoints, I have done this soooo often because it allows me to debug also in cases like production, where I might not be able use breakpoints.

Modern Debugging

I hope you are excited about the future of debugging !

Quick post to let you know that I spoke of the MediatR nuget package at the BracketShow, check it out : http://bracketshow.com/?id=Jov-7Xygtyo

So I was working on DayTickler, and we suddenly decided to start using Xamarin controls from Telerik(Progress) and Syncfusion. Traditionally, that usually meant downloading the installer and then referencing the proper assemblies from the local drive. Another workflow was to copy the assemblies to the project directory in some sort of “lib” folder so that those assemblies could be used in a CI environment.

Fast forward to 2016  and we have something called Nuget, so i tried using these to achieve the same objective. The first was to add the two nuget feeds to Visual Studio’s Nuget configuration screen. Easy enough and from there, i was able to provide my Telerik credentials (their feed is private) and install the packages. Yay !

But when you commit to Visual Studio Online, there is no way to build because it would now fail on package restore.

The solution is to:

1 – Create a nuget.config file in the solution so that the build server knows where to download nuget feeds from:

2 – Open your build definition, and in the “Feeds and authentication” section, go point to your nuget.config file:

3 – Press “+” near “Credentials for feeds outside the account/collection”, and add the appropriate details.

That’s it ! worked like a charm and there is a “Verify connection” button to ensure all is good.