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All posts tagged “elixir”

There is no magic in Elixir!

If you're anything like me, you probably started to learn Elixir and wanted to skip to the shiny stuff right away. Sure there's some basics to sift through like the data types and specific syntax elements but after that, we can finally build a distributed, scalable, performant masterpiece of an application! - Riiigt? Granted, even if you're a bit more of a sane person, once you get to work with Supervisor, GenServer, Agent and other modules alike, you can't help but feel that things have been simplified a lot for you. That's great but sometimes, this comes at the cost of a framework doing complex magic that you have no hope of deciphering if something ever goes wrong.

I've read a few books on Elixir by now and yes, most of them will tell you that this is not the case in Elixir/OTP and things are actually really simple internally but... that's exactly what someone with lost of complex magic in their modules would say, eh! In short, You've probably read about this topic but you probably also didn't believe it. If you have not yet done your own research, this article is here to slap some code in your face to proof to you how thin of a layer a lot of the shiny stuff in Elixir is and provide some insight on why it works so nicely.

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Serving static assets on a subpath in Phoenix

If you create a new Phoenix project, without using the --no-html flag, a static plug will be added to your endpoint. Because of this, a lot of people recommend to just edit that, if you want to serve static files from a subdirectory. However, this can get a bit tricky if you have data stored in different directories - or use Phoenix purely as an API.

When someone asked about this on the elixir-lang Slack, my first response was:

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Phoenix end-to-end testing in real life


There are lots of articles on testing in Elixir, and probably ten times as many for each Javascript frontend framework. But what if we want to test all of it together? - Be advised that end-to-end tests do not replace unit and integration tests on either the backend or frontend, however, I think they do have their place in a good test suite for the following reasons:

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Implementing MQTT in Elixir: Part 1 - Intro and Setup

Library Source Code at the end of this article: Rayman git repo
Playground Source Code at the end of this article: Rayman Playground git repo


This article is the first in a series of posts about creating a Hex package in Elixir that will implement a common network protocol. In this case, the protocol in question is MQTT. We will implement the MQTT protocol based on the MQTT 3.1.1 specifications, from the ground up, leveraging Elixir's pattern matching for easily processing binary data.

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Elixir: Testing protected Phoenix controllers

A common problem

Testing protected endpoints in Phoenix controllers is a topic that sparks confusion - at best, and controversy at worst - amongst a surprising lot of people. When using Guardian or other pluggable ways of authorizing requests, this behaviour has to be taken into consideration for controller tests. Multiple pull requests in the Guardian repository were working towards a solution for this, Guardian Backdoor, which has now been moved into its own repository.

While this will certainly solve this issue for Guardian users in the future, let's explore a simple, fast approach for authorization bypassing that can be used with any kind of plug based authentication pipeline.

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