namtx

Thoughts about Rails Presenters

This is a collection of links, examples and rants about Presenters/Decorators in Rails.

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The "Decorator" pattern slowly started gaining popularity in Rails several years ago. It is not part of core Rails, and there's many different interpretations about how it should work in practice.

Jay Fields wrote about it in 2007 (before he switched back to Java and then Clojure): http://blog.jayfields.com/2007/03/rails-presenter-pattern.html

namtx

PSQL

Magic words:

psql -U postgres

Some interesting flags (to see all, use -h):

• -E: will describe the underlaying queries of the \ commands (cool for learning!)
• -l: psql will list all databases and then exit (useful if the user you connect with doesn't has a default database, like at AWS RDS)

namtx

# 1. Clear retry set

Sidekiq::RetrySet.new.clear

# 2. Clear scheduled jobs 

Sidekiq::ScheduledSet.new.clear

# 3. Clear 'Processed' and 'Failed' jobs

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// for multiple requests
let isRefreshing = false;
let failedQueue = [];

const processQueue = (error, token = null) => {
  failedQueue.forEach(prom => {
    if (error) {
      prom.reject(error);
    } else {
      prom.resolve(token);

namtx

// Credit to https://stackoverflow.com/a/59843241/3422559

import { useEffect, useRef } from "react";

const usePrevious = (value, initialValue) => {
  const ref = useRef(initialValue);
  useEffect(() => {
    ref.current = value;
  });
  return ref.current;