Upgraded Windows 7 to 10 on my MacBook Early 2009

I still have my Early 2009 MacBook for my kids. It runs El Capitan and Windows 7 (bootcamp). Since the support for Windows 7 ended on January 14 2020 an upgrade was needed. Unfortunately the bootcamp 3 that comes with El Capitan doesn’t support any version higher.

Image from The Verge

A quick search on internet learned that upgrading Windows 7 to Windows 10 was easy. Just download the Media Creation Tool and download the bootcamp 4 zip for the updated drivers.

After 3 hours my old MacBook was running Windows 10 with the correct drivers. In the references all downloads are linked. The youtube link makes it dummy proof.
Maybe upgrading to macOS Catalina next time …


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Bogus – testdata generator

Photo by Steve Harvey on Unsplash


Creating testdata is not my favourite task. With bogus I can define the rules the data must adhere and generate as much data as I need.

The rules are setup with fluent syntax and reminds me of AutoMapper configuration. When you set the Randomizer the data can be generated inside your testcode and produce the same ‘random’ set of data every time.

Bogus.Randomizer.Seed = new Random(12345678);
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EF core: entity cannot be tracked

We use EF core to store a bulk of data with an auto-number primary key. The auto-number is an Identity column in Sql Server. When inserting a large amount of records with related children we encounter this error:

System.InvalidOperationException entity cannot be tracked because another instance with the same key value is already being tracked

The github bug that described the same bug: Adding multiple new entities at the same time results in System.InvalidOperationException entity cannot be tracked because another instance with the same key value is already being tracked #13937 The same message, but explicit no use of identity. This got us thinking.

Digging a little deeper we discovered that the TemporaryIntValueGenerator used in EF core used int.minvalue + 1000. That is the first temporary Id used in EF core to track newly created records with an Identity column. Our exception occurs with a large amount of record, maybe 1000? Would the identity value generated in Sql already be used as a temporary value? The identity columns we use start at -2147483648 (int.minvalue) and increase by 1.

We implemented our own TemporaryNumberValueGenerator that start with 214748364 (int.maxvalue / 10) and use that in the OnModelCreating override:

protected override void OnModelCreating(ModelBuilder m) {
    .Property(x => x.Id)
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Computer setup COVID-19 update

I invested in a good computer setup for working-from-home a while ago. When the lockdown for COVID-19 came I was prepared. Still I made some changes and investments to go from one-day-a-week to fulltime working-from-home. Time for an update.

No cable management and I love it

The laptop

I’ve raised my laptop so I can see the slack updates next to my actual work. The clear pastic stand was from when I used only my laptop. After buying my 24 inch monitor it was stuffed away somewhere. Luckily I could still find it and raise my laptop to eye level.

Now that my laptop is always open (used it clamshell mode before) the webcam bothered me. I bought some webcam covers and installed them on all my laptops. Just for some ease of mind.

With everybody working/learning from home my wifi wasn’t stable enough for remote desktop. I bought the thunderbolt UTP adapter and use a wired connection now. Network connection and speed are stable now.


Slack, Skype and Zoom are the places we meet-up. For some privacy and better call quality I use the AirPods 2. Connecting to Apple devices is as easy as clicking a button. The wireless charging case is a nice feature too.

My logitech K800 keyboard and Performance MX mouse use the unifying receiver. Seemed to be vulnerable for hacking. Logitech released an update and installation was easy. https://support.logi.com/hc/articles/360035037273 (Firmware Update Tool)

Sometimes writing with pen on paper is needed. I have a stack of post-it notes next to my case with pens.

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Logging from Automapper

We’ve been using automapper to convert objects for some time. Now I have the need for logging to help bugtracking. Below a short list of sources how we set this up.

services.AddTransient(serviceprovider => {
   var cfg = serviceprovider.GetService<MapperConfiguration>();
   // inject the serviceprovider so everything is available
   // and the ILogger is too
   return cfg.CreateMapper(serviceprovider.GetService);
Func<ResolutionContext, ILogger> createLogger = (c) =>
   c.Mapper.ServiceCtor.Invoke(typeof(ILogger)) as ILogger;
config.CreateMap<ObjectA, ObjectB>()
      .ConvertUsing((s, d, c) => {
         // important stuff removed ....
         var logger = createLogger(c);
         logger.LogWarning("Something happend");

And now you’ll need a serviceprovider when unittesting. Thank you AutoMoqCore.

var automoqer = new AutoMoqer();
var configuration = automoqer.Create<AutomapperConfiguration>();
var mapper = configuration.CreateMapper(automoqer.Create);
// now test the mapping configuration with the mapper instance

We managed to find the bugs and fixed them. We’ll be using this logging solution with automapper from now on.

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