Fabian Kostadinov

How to test Firestore security rules web v9 with Jest for your Angular app

Previously, I wrote why using Karma as a test runner to unit test your Firestore security rules for your Angular app is a bad idea. Let’s see then how you can use Jest in combination with Firebase Firestore emulators. I’ll be using Angular v14, Firebase web v9, the node package @firebase/rules-unit-testing v2.0.5 and Jest v29.3.

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Do not use Karma & Jasmine for unit testing Firestore Security Rules in your Angular app!

I’m writing an Angular 14 app with Google Firebase Firestore as a database. I assumed that developing the Firestore Security Rules with Firebase web v9 by writing Karma/Jasmine unit tests should be not too hard. After all, Karma is Angular 14’s default test runner, no? Turns out that using Karma to develop or test Firestore Security Rules is a bad idea. You should use Jest (or maybe Mocha) instead.

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How I found and cashed in a bitcoin wallet from 2011

A few days ago I found a Bitcoin wallet.dat on a Macbook from 2011. Here is how I managed to cash in on it.

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Basics of vector algebra

Understanding vector algebra is a prerequisite to selecting meaningful distance metrics for text embeddings. For the fun of it, let’s recall some of the basics.

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Introduction to Lucene 7 OpenNLP - Part 4

I have written three blog posts about how to use Lucene 7 and OpenNLP to index part-of-speech tags and then use phrase queries to search on these tags. What I haven’t shown so far is what’s so cool about having such a capability.

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