I, [2024-01-21T06:22:17.484221 #2698200] INFO -- : [4cdad7a4-8617-4bc9-84e9-c40364eea2e4] test
I, [2024-01-21T06:22:17.484221 #2698200] INFO -- : [4cdad7a4-8617-4bc9-84e9-c40364eea2e4] more
I, [2024-01-21T06:22:17.484221 #2698200] INFO -- : [6e047fb3-05df-4df7-808e-efa9fcd05f87] test
I, [2024-01-21T06:22:17.484221 #2698200] INFO -- : [6e047fb3-05df-4df7-808e-efa9fcd05f87] more
I, [2024-01-21T06:22:17.484221 #2698200] INFO -- : [53a240c1-489e-4936-bbeb-d6f77284cf38] nope
I, [2024-01-21T06:22:17.484221 #2698200] INFO -- ...
There are a few tools to combat the dreaded n+1 queries. The bullet gem notifies you of missing eager-loading, and also if there is too much eager-loading. strict_loading in Rails 6.1+ forces developers to explicitly load associations on individual records, for a single association, for an entire model, or globally for all models.
But you can also actually **write spe...
Today I learned that you can animate HTML elements using the Web Animation API's method .animate(keyframes, options) (which seems to be Baseline for all browsers since 2022).
const fadeIn = [{ opacity: 0 }, { opacity: 1 }] // this is a keyframe example
const container = document.querySelector('.animate-me')
const animation = container.animate(fadeIn, 2000) // I am just using the animation duration as option here but it can also be given an object
// the animation object can be used for things like querying timings or stat...
Multiply by 1x the unit:
$number = 13
$length = $number * 1px // => 13px
Divide by 1x the unit:
$length = 13px
$number = $length / 1px // => 13
the result of an addition or subtraction between two numbers of different units is expressed in the first member’s unit
Thus, to convert a number, add it to 0 of the desired unit:
$duration: .21s
$duration-in-milliseconds: 0ms + $duration // => 210ms
An example is storing a transition duration as CS...
Ruby methods which load from a Yaml file, like YAML.safe_load or YAML.safe_load_file, support passing freeze: true to deep-freeze the entire contents from the Yaml file.
This is available by default on Ruby 3.0 and newer. On older Rubies, you can install psych 3.2.0 or newer for :freeze support.
As an example, consider the following Yaml file:
---
message:
- hello
- universe
foo:
bar:
baz: "example"
We can now load it as usual, but pass freeze: true.
>> test = YAML.safe_load_file('example.yml', fre...
Your development server is usually running on an insecure HTTP connection which is perfectly fine for development.
If you need your local dev server to be accessible via HTTPS for some reason, you need both a certificate and its key. For a local hostname, you need to create those yourself.
This card explains how to do that and how to make your browser trust the certificate so it does not show warnings for your own certificate.
To just create a certificate for localhost, you can use the following command....
We generally use multiple application servers (at least two) and you have to search on all of them if you don't know which one handled the request you are looking for.
Rails application logs usually live in /var/www/<project-environment-name>/shared/log.
Web server logs usually live in /var/www/<project-environment-name>/log.
grep / zgrep
You can use grep in this directory to only search the latest logs or zgrep to also search older (already zipped) logs. zgrep is used just like grep ...
Note: Modern Rails has two build pipelines, the asset pipeline (or "Sprockets") and Webpacker. The principles below apply for both, but the examples shown are for Sprockets.
Every page in your application uses many assets, such as images, javascripts and stylesheets. Without your intervention, the browser will request these assets again and again on every request. There is no magic in Rails that gives you automatic caching for assets. In fact, if you haven't been paying attention to this, your application is probabl...
Phusion Passenger changed the way how it gets restarted several times. Through the project's history, these all were valid:
touch tmp/restart.txtsudo passenger-config restart-app /path/to/apppassenger-config restart-app /path/to/appYou should not need to know which one to use. Instead, the capistrano-passenger gem will choose the appropriate restart mechanism automatically based on your installed the passenger version.
Add to your Gemfile:
gem 'capistr...
Here are some hints on best practices to maintain your tasks in larger projects.
lib/tasks/*.lib/scripts/* as folder.For readability and testing it's easier to keep your tasks slim.
Example:
lib/gitlab/maintenance_tasks/user_export.rb:
module Gitlab
module MaintenanceTasks
class UserExport
...
Version 3.7.0 broke some things in complex forms. Sorry for that. Concurrent user input is hard.
This change fixes two regressions for form field watchers, introduced by 3.7.0:
Cannot destructure property { disable } of null....
If you have an element with significant border-radius (e.g. 50% for a circle) and you want inline content (i.e. text) to flow around it, do it like this:
float: right or float: left
content-box for the element's shape, i.e. without margin, padding and border. shape-outside: content-box
margin where you want it, e.g. 10px left and bottomshape-margin to the same size ...These steps are now part of Spreewald.
This note describes a Cucumber step that lets you write this:
Then I should see a table with the following rows:
| Bruce Wayne | Employee | 1972 |
| Harleen Quinzel | HR | 1982 |
| Alfred Pennyworth | Engineering | 1943 |
If there are additional columns or rows in the table that are not explicitely expected, the step won't complain. It does however expect the rows to be ordered as stat...
In the following example the method update_offices_people_count won't be called when office_id changes, because it gets overwritten by the second line:
after_save :update_offices_people_count, :if => :office_id_changed? # is overwritten …
after_save :update_offices_people_count, :if => :trashed_changed? # … by this line
Instead write:
after_save :update_offices_people_count, :if => :office_people_count_needs_update?
private
def office_people_count_needs_update?
office_id_changed? || trashed_changed?
end
Or...
When using virtual attributes, the attached trait can be useful to automatically copy errors from one attribute to another.
Here is a typical use case where Paperclip creates a virtual attribute :attachment, but there are validations on both :attachment and :attachment_file_name. If the form has a file picker on :attachment, you would like to highlight it with errors from any attribute:
class Note < ActiveRecord::Base
has_attached_file :attachment
validates_attachment_presence :a...
I recently did a quick research on how to better write down multiline statements like this:
# Dockerfile
RUN export DEBIAN_FRONTEND=noninteractive \
&& apt-get update \
&& apt-get dist-upgrade -y \
&& apt-get install --no-install-recommends --no-install-suggests -y \
ca-certificates \
curl \
unzip
It turns out, there is! Buildkit, the tool behind docker build added support for heredoc strings in May 2021.
Now we could refactor the code above like this:
A list of clever debugging tricks. TOC:
RubyMine has a collaboration feature called "Code With Me". Using it, you can invite someone into your local editor to work together. This is nicer to the eyes and much more powerful than sharing code through some video chat.
Getting started is really simple:
You can ignore certain commits when using git blame with the --ignore-revs-file option. This is handy to ignore large rubocop commits or big renamings in your project. You can add and commit a .git-blame-ignore-revs file in your project to track a list of commits that should be ignored.
# a list of commit shas
123...
456...
Use git blame with the --ignore-revs-file option and ignore the SHAs specified in .git-blame-ignore-revs.
git blame --ignore-revs-file .git-blame-ignore-revs
If you want to use this flag by def...
It is generally discouraged to load your JavaScript by a <script src> tag in the <head>:
<head>
<script src="app.js"></script>
</head>
The reason is that a <script src> tag will pause the DOM parser until the script has loaded and executed. This will delay the browser's first contentful paint.
A much better default is to load your scripts with a <script src defer> tag:
<head>
<script src="app.js" defer></script>
</head>
A deferred script has many useful properties:
One of the many useful features of TextMate is autocompletion of words. If I were in TextMate right now, I could write "au[tab]", and it would complete it to "autocompletion". RubyMine can do this, too. When you write a word (e.g. a variable name), just hit ALT + / repeatedly and it will offer all completions for the letters you typed. This action is called Cyclic Expand Word in RubyMine / IntelliJ IDEA.
This feature keeps you from mistyping variable names, saves you keystrokes and speeds up development. ~10 keystrokes to the price ...
The linked article suggests an interesting way to speed up tests of Rails + Postgres apps:
PostgreSQL allows the creation of “unlogged” tables, which do not record data in the PostgreSQL Write-Ahead Log. This can make the tables faster, but significantly increases the risk of data loss if the database crashes. As a result, this should not be used in production environments. If you would like all created tables to be unlogged in the test environment you can add the following to your...
Don't use be_true to check if a value is true. It actually checks if it anything other than nil or false. That's why it has been renamed to be_truthy in recent RSpec versions.
The same thing holds for be_false, which actually checks if a value is not "truthy".
If you want to check for true or false in RSpec 2, write this instead:
value.should == true
value.should == false
If you want to check for true or false in RSpec 3+, write this instead:
e...
When your model is using a callback like before_save or before_validation to calculate an aggregated value from its children, it needs to skip those children that are #marked_for_destruction?. Otherwise you will include children that have been ticked for deletion in a nested form.
class Invoice < ApplicationRecord
has_many :invoice_items
accepts_nested_attributes_for :invoice_items, :allow_destroy => true # the critical code 1/2
before_save :calculate_and_store_amount # the crit...