A datetime in MySQL does not have a zone. It just stores the literal string "2010-05-01 12:00:00". That means that Rails must make...
...mode Rails assumes that your application lives in the same time zone as your server's local zone settings. In this mode ActiveRecord will not try to convert times coming...
...entering only http://example.com/). If you want to make a request to that site's web server without actually talking to www.example.com (e.g. because this is a load balancer...
...s address but you want to access one specific machine), you cannot just request machine1.example.com or localhost as the above vhost will redirect your request. When talking HTTP 1.1, your...
...filled out at the same time, there is no built-in validation. I've seen different solutions in the wild, each with different downsides: Private method referenced via validate: works...
...name, :nickname, xor_presence: true end Validator Here is the validator class; put it somewhere in your project. class XorPresenceValidator < ActiveModel::Validator def initialize(options) @attributes = Array.wrap(options[:attributes]).freeze...
How to ignore new files Globally Add the path(s) to your file(s) which you would like to ignore...
...have multiple exported resources that are identical. There are nodes that provide the same services for failover reasons. It is likely to have duplicate resources, when exporting nagios_check from...
...everything is fine. But when it comes to realizing the resources on the monitoring server, the puppetrun will fail due to the duplicate addresses. So how to mitigate this issue...
can’t find executable rails for rails-3.2.3 (Gem::Exception) ... one of several...
...things might be wrong. You're using RVM It's possible that you have a system-wide gem executable (like rails) that requires a gem that is not available in...
It's not possible to change the bwlimit of Proxmox storages via the Web-UI (at least in Proxmox 7.x). To change the bwlimit you need to use the...
...pvesm command and specify the limit for the desired category. For example to increase the bwlimit for migrations: pvesm set $NAME_OF_STORAGE --bwlimit migration=$INTEGER_LIMIT # example
On your local system that only hosts non-critical development data and only you have access to, you can store MySQL's root password in your home directory so you...
...out of the question if there's any confidential data in your databases. Assuming diligent screen-locking, an encrypted hard disk and correct permissions set on your credential file, it...
If you want to to create maps within SASS/SCSS-files, it normally works like this: $some-map: (key1: value1, key2: value2) However, some maps can get big really fast, if they...
...since 2011 and it hasn't been resolved since then. Writing a map likes this: $some-map: ( key1: value1, key2: value2 ) confuses the SASS-parser and you will get an...
Sometimes it is useful to define a named scope by implementing a static method with the scope's name on the scoped class. For instance, when a method should decide...
...which existing scope should be the next link in the scope chain. Take this class for example: class Meal < ActiveRecord::Base named_scope :for_date, lambda { |date| :conditions => { :date => date...
SVG files are often much larger than necessary, containing comments, metadata, hidden elements etc. Optimize them with this tool. Web UI: https://jakearchibald.github.io/svgomg/ Binary: https://github.com/svg/svgo
...for a properly scaling SVG, you need to keep the viewBox attribute. There's an option --disable=removeViewBox for this...
A comprehensive introduction to sending HTML emails. Intro: HTML email: Two words that, when combined, brings tears to a developer’s eyes. If you’re a web developer, it’s...
...in your career, whether you like it or not. Coding HTML email is old school. Think back to 1999, when we called ourselves “webmasters” and used Frontpage, WYSIWYG editors and...
Spreewald's patiently repeats the given block again and again until it either passes or times out. Be careful to give patiently a block that can actually be repeated. E.g...
...the field variable that was defined outside of the block (it's the variable set from the Given block's arguments). Because of this, during the first repetition the value...
...run rake and your code is causing an exception which is not the one shown in your terminal. Rails tries to catch this exception and clean up constants but -- while...
...it's still booting up -- fails on this which causes another exception: rake aborted! cannot remove Object::ClassMethods Running rake with the --trace parameter will give you no love; the...
Capistrano automatically logs each (successful) deployment into a file on your application servers. It is located at the root of your server's project folder, i.e. the parent of releases...
...and current, like so: /var/www/your-project$ ls current log releases repo revisions.log <--- here shared Each line in that file contains the deployed branch, commit, release ID, and username (was read from...
Having a unique selector for an element is useful to later select it from JavaScript or to update a fragment with an Unpoly. Haml lets you use square brackets ([]) to...
...with ActiveRecord instances, which have a persisted #id and will hence generate the same selector over multiple renderings of the same view. Example - @users.each do |user| .row[user] = user.name
Ruby's standard library includes a class for creating temporary directories. Similar to Tempfile it creates a unique directory name. Note: You need to use a block or take care...
...of the cleanup manually You can create a prefix and suffix e.g. Dir.mktmpdir(['foo', 'bar']) => /tmp/foo20220912-14561-3g93n1bar You can choose a different base directory than Dir.tmpdir e.g. Dir.mktmpdir('foo', Rails.root.join('tmp...
...is pretty useful, but manipulating values of arrays can be awkward because of its syntax. Consider the following users table which each example below will start from: name topics
Bob {llamas} (PostgreSQL uses curly braces to represent arrays, true story.) Adding values Use the array_cat function, or the || operator. These calls will add the values "cats...
...the transcluded content before adding it to the DOM. # Directive template: """ """ transclude: true link: (scope, element, attributes, _controller, transclude) -> transclude (content) -> # Do custom stuff element.find('.wrapper').append(content)
...much more you can do with the transclusion function. For an in-depth introduction, see this Guide to Angular Transclusion. Also read the Angular docs on this...
When using the asset pipeline your assets (images, javascripts, stylesheets, fonts) live in folders inside app: app/assets/fonts app/assets/images app/assets/javascripts app/assets/stylesheets With the asset pipeline, you can use the...
When you deploy, Rails runs assets:precompile which precompiles all assets into static files that live in public/assets. This way you have all the performance of static files...
...we use pagination Exercises Create 7500 movies in MovieDB (hint: Doing it in a single transaction is much faster). Load the movies index and measure how long it renders.
...the movies index render now? Inspect the HTML generated by will_paginate. Customize the style so it matches the look of your MovieDB. tail -f log/development.log and see which queries...
ActionMailer per default uses http as protocol, which enables SSL-stripping. When a logged-in user follows an http link to your application, it sends the cookies along with it...
...to send emails from public parts of your application with HTTP links and emails from SSL-protected parts with HTTPS, build a before_filter. If you need certain links with...
Ruby's regular expressions can be represented differently. When serializing them, you probably want to use inspect instead of to_s. For the examples below, consider the following Regexp object...
>> regexp.to_s => "(?mi-x:^f(o+)!)" inspect As the Ruby docs say: Perhaps surprisingly, #inspect actually produces the more natural version of the string than #to_s...
Middleman is a static page generator that brings many of the goodies that Rails developers are used to. Out of the box, Middleman brings Haml, Sass, helpers etc. However, it...
...these gems to the Gemfile: group :test do gem 'cucumber' gem 'spreewald' gem 'capybara' gem 'selenium-webdriver' # Only for running tests in a real browser (suggested) gem 'capybara-screenshot' # Optionally...