You want to use <input type="number"> fields in your applications.
However, your desktop users may encounter some weird quirks:
to_i in Ruby) you'll end up with wrong values (like 1 instead o...Rails includes a way to see what an e-mail will look like.
All you need to do is implement a preview-class in spec/mailers/previews/notifier_preview.rb:
class NotifierPreview < ActionMailer::Preview
def welcome
Notifier.welcome(User.first)
end
end
And adapt the preview load path in your application.rb:
config.action_mailer.preview_path = "#{Rails.root}/spec/mailers/previews" # this is already set as default by Rails
Then a preview will be available in the browser at <http://lo...
Find-as-you-type boxes are usually built by observing changes in a text field, and querying the server via AJAX for search results or suggestions when the field has changed.
A common problem with this implementation is that there is no guarantee that AJAX responses are evaluated in the same order as the original requests. The effect for the user is that the search results are flashing back and forth while the user is typing the query, and when the user has stopped typing the last results don't always match the final query.
Workarounds
----...
To show your key inputs on screen, e.g. for a screencast or screen sharing, you can use screenkey.
A really useful flag is --show-settings. Running screenkey --show-settings shows a settings window, which allows you to easily adjust the key overlay.
The option Select window/region is especially useful for choosing where the overlay is placed.
A Rails script lives in lib/scripts and is run with bin/rails runner lib/scripts/.... They are a simple tool to perform some one-time actions on your Rails application. A Rails script has a few advantages over pasting some prepared code into a Rails console:
Although not part of the application, your script is code and should adhere to the common quality standards (e.g. no spaghetti code). However, a script...
When testing JavaScript functionality in Selenium (E2E), you may need to access a class or function inside of a evaluate_script block in one of your steps. Capybara may only access definitions that are attached to the browser (over the window object that acts as the base). That means that once you are exporting your definition(s) in Webpacker, these won't be available in your tests (and neither in the dev console). The following principles/concepts also apply to Sprockets.
Say we have a StreetMap class:
// street_map.js
class S...
git --fixup is very handy to amend a change to a previous commit. You can then autosquash your commits with git rebase -i --autosquash and git will do the magic for you and bring them in the right order. However, as git --fixup wants a ref to another commit, it is quite annoying to use since you always have to look up the sha of the commit you want to amend first.
Inspired by the [shortcut to checkout recent branches with fzf](https://makandracards.com/makandra/505126-g...
When doing some meta-programming magic and you want to do something for all attributes of a class, you may need to access connection or some of its methods (e.g. columns) during class definition.
While everything will be fine while you are working on a project that is in active development, the application will fail to boot when the database is missing or has no tables. This means that Raketasks like db:create or db:migrate fail on a freshly cloned project.
The reason is your environment.rb which is loaded for Raketasks and calls...
87.140.79.42 - - [23/Jan/2024:09:00:46 +0100] "GET /monitoring/pings/ HTTP/1.1" 200 814 "-" "Ruby"
87.140.79.42 - - [23/Jan/2024:09:00:46 +0100] "GET /monitoring/pings/ HTTP/1.1" 200 814 "-" "Ruby"
87.140.79.41 - - [23/Jan/2024:09:00:46 +0100] "GET /monitoring/pings/ HTTP/1.1" 200 814 "-" "Ruby"
87.140.79.42 - - [23/Jan/2024:09:00:46 +0100] "GET /monitoring/pings/ HTTP/1.1" 200 814 "-" "Ruby"
Count and sort the number of requests for a single IP address.
awk '{ print $1}' test.log | sort...
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...