...exception, Rails will look at the exception's class and choose an appropriate HTTP status code and error page for the response. For instance, an ActiveRecord::RecordNotFound will cause Rails...
...render a red "The page you were looking for doesn't exist" with a status code of "404" (not found). The mapping from exception classes to error types is a...
Slow test suites are a major pain point in projects, often due to RSpec and FactoryBot. Although minitest and fixtures are sometimes viewed as outdated, they can greatly improve test...
We adopted a project using minitest and fixtures, and while it required some initial refactoring and establishing good practices, the faster test suite was well worth it! Stick with...
SVG is an acronym for "scalable vector graphics". SVGs should be used whenever an image can be described with vector instructions like "draw a line there" or "fill that space...
...they're not suited for photographs and the like). Benefits are the MUCH smaller file size and the crisp and sharp rendering at any scale. It's a simple, old...
...s calc(100 - l)); Here is what happens: from currentColor tells hsl() to start with the value of currentColor. calc(h + 180) rotates the color hue by 180 degrees, i.e...
...to the opposite of the color wheel. s keeps saturation unchanged. calc(100 - l) inverts lightness. For example, 0% becomes 100%, and 100% becomes 0%. Example usage .demo { --inverted-color...
Why secure-only cookies used to be necessary Cookies have an optional secure flag. It tells the browser to not send the cookie for a non-https request.
...users from http:// to https://. The reason was that most users will only enter a scheme-less domain like makandra.de into their location bar, which will default to http://makandra.de...
Understanding your type of cronjob Some cronjobs must only run on a single server. E.g. when you run nightly batch operations on the database, it should probably run on a...
...single server. Running it on multiple servers would likely result in deadlocks or corrupt data. Some cronjobs must always run on all servers. E.g. starting a sidekiq process on reboot...
Migrating data from a legacy into a new system can be a surprisingly large undertaking. We have done this a few times. While there are significant differences from project to...
...project, we do have a list of general suggestions. Before you start, talk to someone who has done it before, and read the following hints: Understand the old system
...can reset the min-width. Say you have a simple grid layout: .container .first-item .second-item .third-item .container display: grid grid-template-columns: 100px 1fr 100px Your expectation...
...correct as the grid layout will try to do that: +---------+----------------------------+---------+ | | - 10 characters long | | +---------+----------------------------+---------+ However, if .second-item's content is too large to fit into the reserved space, it will...
...or position: fixed display: inline-block display: table-cell overflow: (not "visible") and more, see https://developer.mozilla.org/en-US/docs/Web/Guide/CSS/Block_formatting_context Example: A fluid main area with a right sidebar
...you don't want either column to clear content of the other. Float the sidebar to the right and you're set: its content now renders in the sidebar's...
The following two hints are taken from Github's Ruby style guide: If your regular expression mentions a lot of forward slashes, you can use the alternative delimiters %r(...), %r...
...complex, you can use the /x modifier to ignore whitespace and comments: regexp = %r{ start # some text \s # white space char (group) # first group (?:alt1|alt2) # some alternation end
In a nutshell: Use git rebase --onto target-branch source-commit target-branch means "branch you want to be based on" source-commit means "commit before your first feature commit...
...Let's say my-feature-branch is based on master and we want it to be based on production. Consider this history: %%{init: { 'gitGraph': {'showCommitLabel': true, 'mainBranchName': 'production'}} }%% gitGraph
...Doing that enables e.g. man in the middle attacks. If you accept only a single expired and known certificate, you are much less in trouble. Setup All the solutions described...
...below use a verify_callback for the request's OpenSSL::X509::Store where you can specify a lambda to adjust its verification response. Your callback must return either true or...
...the code below to check whether the browser can make connections to the current site: await isOnline() // resolves to true or false The code The isOnline() function below checks if...
...you can make real requests by re-fetching your site's favicon. If the favicon cannot be downloaded within 6 seconds, it considers your connection to be offline. async function...
When you need to find out in which kind of spec you are during run-time, it's definitely possible. It's a lot easier in RSpec 2+.
...consider this global before block where you'd want to run some code for specific specs only: config.before do # stuff that_fancy_method # more stuff end RSpec 2+
...maintain. There are some good practices for writing a changelog that adds value, please stick to these. Add a notice to the README's contribute section about the changelog
...this project will be documented in this file. This project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html). ## Unreleased - Added `Foo#foo` method. ## 1.0.0 - 2017-06-20 ### Breaking changes - Renamed `Foo...
If your railscomplete-deployment uses the net-ssh-gem please ensure you use version 5.2.0 or newer to ensure you can deploy via Capistrano. It's best to use...
To completely remove the old host key on the client run: # remove host entry ssh-keygen -f "$HOME/.ssh/known_hosts" -R appserver.makandra.de # remove IP entry ssh-keygen -f "$HOME/.ssh/known_hosts" -R $(getent...
...uses a "real" time zone or :local, and if config.active_record.time_zone_aware_attributes is set to false or not. With time zones configured, always use .current for Time, Date, and...
...which hold time zone information and Time.now only in those that run with the server's time. If you don't, bad things can and will happen. More information can...
...more complicates it is easier to understand and to process. Note: In case a string does not match the pattern, .match will return nil. With Ruby 2.4 the result of...
...transformed to a Hash with named_captures. This allows you to use methods like slice or fetch on the result. Example with a multiple assignment PRODUCT_PATTERN = /\A(.+) S\/N...
...to do a VACUUM FULL without holding an exclusive lock during processing. There is still a need of one exclusive lock at the beginning and the end of the repacking...
...affected table. Warning pg_repack writes a copy of the whole table. The database server needs to have at least ($size_of_biggest_table * 2) + some buffer free disk space...
When your application is open for public sign up and sends out transactional e-mails to a large number of users, e-mail deliverability becomes an issue. E-mail providers...
...work hard to eliminate spam and have put in place relatively tight checks what kinds of emails they will accept, and from whom. To that end we use tools like...
...and autoload paths. They do NOT create a module for namespacing. This is intuitive, since there normally is no module Model, or module Controller. If you want to add a...
├── models ├── uploaders # No config needed ├── util # No config needed └── workers # No config needed Sometimes it's handy to group files within a directory, but not reflect that grouping within...
...with an english name. This makes you code easier to read and is also suggested by Rubocop's Style/GlobalVars cop. Example before: if 'foo' =~ /foo/ puts $~[1] # => foo end
...following content: require 'English' List of global aliases $ERROR_INFO => $! $ERROR_POSITION => $@ $FS => $; $FIELD_SEPARATOR => $; $OFS => $, $OUTPUT_FIELD_SEPARATOR => $, $RS => $/ $INPUT_RECORD_SEPARATOR => $/ $ORS => $\ $OUTPUT_RECORD_SEPARATOR => $\ $INPUT_LINE_NUMBER...
...a minifier that is good enough for most cases. If you're looking to squeeze out as many bytes as possible, you can consider compressing with Terser instead.
...will increase your build times significantly, but produce the smallest output: Terser (3 pass) Terser (1 pass) esbuild application.js 163.6 kB 163.7 kB 181.6 kB application.js (gzipped)
Understand at least the following CSS concepts: Classes Selecting elements for styling Basic styling (color, typography, spacing) The box model Inline elements vs. block elements Ways to layout elements...
...Learn how to use your browser's "inspect" feature and how you can see which CSS styles are applied to an element Learn what a "reset stylesheet" is.