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defmodule TimeFormat do
def format(seconds) do
hours = div(seconds, 3600)
remainder = rem(seconds, 3600)
minutes = div(remainder, 60)
seconds = rem(remainder, 60)
format(hours, minutes, seconds)
end
defp format(0, minutes, seconds), do: "#{minutes}:#{pad(seconds)}"
@nathanl
nathanl / jeg_stateful_web_applications.md
Last active October 31, 2019 16:48
James Edward Gray II describing the ability to build *stateful* web application in Elixir

James Edward Gray II

Quote from Elixir Mix 63 - "063: Designing Elixir Systems With OTP with Bruce Tate and James Gray", starting at 01:03:13

"I've worked at a bunch of companies building web apps for a long time, and I keep seeing this same pattern, and it haunts me. In the web world, all we want is these long interactions with people, and we live in this stateless world. So what we do is, the first part of every request, we do thirty queries to re-establish the state of the world that we just forgot a few seconds ago after the last request. And then we go forward and make one tiny step forward, and then we forget everything again, so that when the next request comes in we can do thirty queries to put it all back and make one more tiny step. And I kept thinking, "there has to be a better way than this, right?"

And if you look at web advancements over the years, most of the things we're doing are

@wosephjeber
wosephjeber / instructions.md
Last active January 8, 2025 19:03
Ecto migration for renaming table with indexes and constraints

Renaming table in Ecto migration

I recently wanted to rename a model and its postgres table in a Phoenix app. Renaming the table was simple and documented, but the table also had constraints, sequences, and indexes that needed to be updated in order for the Ecto model to be able to rely on default naming conventions. I couldn't find any examples of what this would look like but was eventually able to figure it out. For anyone else in the same situation, hopefully this example helps.

In the example below, I'm renaming the Permission model to Membership. This model belongs to a User and an Account, so it has foreign key constraints that need to be renamed.

defmodule MyApp.Repo.Migrations.RenamePermissionsToMemberships do
  use Ecto.Migration
class ActiveRecord::Relation
# Preload one level a chained association whose name is specified in attribute.
def preload_chain(attribute, collection: nil)
preloader = ActiveRecord::Associations::Preloader.new
preloader.preload(collection || records, attribute.to_sym)
self
end
# Preload all levels of a chained association specified in attribute. Will cause infinite loops if there are cycles.
def deep_preload_chain(attribute, collection: nil)
@brycejohnston
brycejohnston / ubuntu1804_ruby_elixir.md
Last active June 6, 2022 11:56
Ubuntu 18.04 / 18.10 Ruby and Elixir Development Setup

Ubuntu 18.04 / 18.10 Ruby and Elixir Development Setup

Guide to setting up a new Ubuntu 18.04 dev environment with Ruby and Elixir installed with the asdf version management tool.

Update system and install prerequisite packages

Some of these packages may already be installed

sudo apt-get install make binutils gcc build-essential \
 git curl zlib1g-dev openssl libssl-dev libreadline-dev \
@nikneroz
nikneroz / authorization.ex
Created December 11, 2017 09:25
Elixir + Phoenix Framework 1.3 + Guardian 1.0 + JWT(Refresh, Revoke, Recover) + Comeonin
# Elixir + Phoenix Framework 1.3 + Guardian + JWT(Refresh, Revoke, Recover) + Comeonin
### User model bootstrap
Let's generate User model and controller.
```bash
mix ecto.create # create DB table
mix phx.gen.json Accounts User users email:string password_hash:string # scaffold users structure
```
@Luzifer
Luzifer / README.md
Last active March 31, 2025 18:54
Running docker-compose as a systemd service

Running docker-compose as a systemd service

Files

File Purpose
/etc/compose/docker-compose.yml Compose file describing what to deploy
/etc/systemd/system/docker-compose-reload.service Executing unit to trigger reload on docker-compose.service
/etc/systemd/system/docker-compose-reload.timer Timer unit to plan the reloads
/etc/systemd/system/docker-compose.service Service unit to start and manage docker compose
@gboudreau
gboudreau / AuthyToOtherAuthenticator.md
Last active July 22, 2025 00:59 — forked from Ingramz/AuthyToOtherAuthenticator.md
Export TOTP tokens from Authy

Exporting your 2FA tokens from Authy to transfer them into another 2FA application

IMPORTANT - Update regarding deprecation of Authy desktop apps

Past August 2024, Authy stopped supported the desktop version of their apps:
See Authy is shutting down its desktop app | The 2FA app Authy will only be available on Android and iOS starting in August for details.

And indeed, after a while, Authy changed something in their backend which now prevents the old desktop app from logging in. If you are already logged in, then you are in luck, and you can follow the instructions below to export your tokens.

If you are not logged in anymore, but can find a backup of the necessary files, then restore those files, and re-install Authy 2.2.3 following the instructions below, and it should work as expected.

@StevenACoffman
StevenACoffman / _MicroService Proxy Gateway Solutions.md
Last active July 15, 2024 05:12
Microservice Proxy/Gateway Solutions

MicroService Proxy Gateway Solutions

Kong, Traefik, Caddy, Linkerd, Fabio, Vulcand, and Netflix Zuul seem to be the most common in microservice proxy/gateway solutions. Kubernetes Ingress is often a simple Ngnix, which is difficult to separate the popularity from other things.

Github Star Trend:

Github Star History for Kong vs traefik vs fabio vs caddy vs Zuul

This is just a picture of this link from March 2, 2019

Originally, I had included some other solution

@nikneroz
nikneroz / Guardian JWT.md
Last active October 10, 2023 19:13
Elixir + Phoenix Framework + Guardian + JWT. This is tutorial and step by step installation guide.

Elixir + Phoenix Framework + Guardian + JWT + Comeonin

Preparing environment

We need to generate secret key for development environment.

mix phoenix.gen.secret
# ednkXywWll1d2svDEpbA39R5kfkc9l96j0+u7A8MgKM+pbwbeDsuYB8MP2WUW1hf

Let's generate User model and controller.