Skip to main content

Generate Test data using Bogus

On one of the projects I’m working on, we needed tons of test data to feed our integration tests. Before we carefully crafted the test data ourselves which worked but was a time consuming and cumbersome process. We got quite bored doing this and decided it was time to find a better alternative.

We ended up using Bogus.

From the documentation:

Bogus is a simple and sane fake data generator for .NET languages like C#, F# and VB.NET. Bogus is fundamentally a C# port of faker.js and inspired by FluentValidation's syntax sugar.

Bogus will help you load databases, UI and apps with fake data for your testing needs.

Getting started

To get started with Bogus, you first need to install the NuGet package in your test project:

Install-Package Bogus
Next step is to create a Faker object and specify the rules for all your properties:
Some of the features of Bogus I really like are:
  • Support for multiple locales: You can generate test data in multiple languages
  • Generate default object data:  You can easily generate realistic test data for a large set of objects like countries, addresses, persons, creditcards, emailaddresses,…
  • A fluent API: Thanks to the Fluent api configuring your rules becomes easy as pie

Remark: If you find the default Fluent API too repetitive, you can use the Bulk api instead:
Labels:

Popular posts from this blog

Podman– Command execution failed with exit code 125

After updating WSL on one of the developer machines, Podman failed to work. When we took a look through Podman Desktop, we noticed that Podman had stopped running and returned the following error message: Error: Command execution failed with exit code 125 Here are the steps we tried to fix the issue: We started by running podman info to get some extra details on what could be wrong: >podman info OS: windows/amd64 provider: wsl version: 5.3.1 Cannot connect to Podman. Please verify your connection to the Linux system using `podman system connection list`, or try `podman machine init` and `podman machine start` to manage a new Linux VM Error: unable to connect to Podman socket: failed to connect: dial tcp 127.0.0.1:2655: connectex: No connection could be made because the target machine actively refused it. That makes sense as the podman VM was not running. Let’s check the VM: >podman machine list NAME         ...
Read more

Azure DevOps/ GitHub emoji

I’m really bad at remembering emoji’s. So here is cheat sheet with all emoji’s that can be used in tools that support the github emoji markdown markup: All credits go to rcaviers who created this list.
Read more

Cache stampede: when our cache turned against us

While investigating some performance issues, we ran into an ASP.NET Core API that cached a fairly expensive aggregation query for 60 seconds. Under normal load, that was fine: one request rebuilds the cache, everyone else reads from it. Under peak load, dozens of requests would arrive in that same expiry window, all see a cache miss, and all fire the same expensive query in parallel. The database didn't like that. That was the moment when our caching layer stopped helping and started hurting. A burst of requests comes in at the same time, all miss the cache, and all go hammer the database or the downstream API at once. That's a cache stampede . The cache was supposed to protect our backend, and for a few hundred milliseconds it did the opposite. Why this happens IMemoryCache.GetOrCreate (and its async sibling) looks like it protects you, but it doesn't add any locking on its own. Look at the naive version: public async Task<Report> GetReportAsync(string key) ...
Read more