Browsers will not send a referrer when linking from HTTPS to HTTP

  • When your site is on HTTPS and you are linking or redirecting to a HTTP site, the browser will not send a referrer.
  • This means the target site will see your traffic as "direct traffic", i.e. they cannot distinguish such hits from a user who directly typed in the URL.

Reasons for this behavior

It's probably because of this RFC:

Clients SHOULD NOT include a Referer header field in a (non-secure) HTTP request if the referring page was transferr...

Compare two jQuery objects for equality

Every time you call $(...) jQuery will create a new object. Because of this, comparing two jQuery collections with == will never return true, even when they are wrapping the same native DOM elements:

$('body') == $('body') // false

In order to test if two jQuery objects refer to the same native DOM elements, use is:

var $a = $('body');
var $b = $('body');
$a.is($b); // true

Jasmine equality matcher for jQuery

See [here](/makandra/34925-jasmine-testing-complex-types-for-e...

PostgreSQL's OVERLAPS operator is not fully inclusive

PostgreSQL supports the SQL OVERLAPS operator. You can use it to test if two date ranges overlap:

=> SELECT ('2001-02-16'::date, '2001-12-21'::date) OVERLAPS
          ('2001-12-20'::date, '2002-10-30'::date);

overlaps
--------
true

An important caveat is that the date ranges are defined as start <= time < end. As such the later date is not included in the range:

=> SELECT ('2001-02-16'::date, '2001-12-21'::date) OVERLAPS
          ('2001-12-21'::date, '2002-10-30'::date);

overlaps
--------
false

Also compar...

Testing terminal output with RSpec

When testing Ruby code that prints something to the terminal, you can test that output.
Since RSpec 3.0 there is a very convenient way to do that.

Anything that writes to stdout (like puts or print) can be captured like this:

expect { something }.to output("hello\n").to_stdout

Testing stderr works in a similar fashion:

expect { something }.to output("something went wrogn\n").to_stderr

Hint: Use heredoc to test multi-line output.

expect { something }.to output(<<-MESSAGE.strip_heredoc).to_stdout...

Usage of RSpec's raise_error

Never use raise_error without specifying the Error you expect.

expect { do_a_lot_of_complicated_stuff }.to raise_error

will be green if you make any error in programming. E.g. a simple typo would make the test above green. The block will catch the Spec:: exception and the test will be happy.

Be sure to always have custom errors in your models and raise them in a manner that lets you know what went wrong.

expect { execute_payment! }.to raise_error(PayPal...

Katapult 0.3.0 released

Katapult 0.3.0 brings Rails 5 and Ruby 2.5 support with a new design, plus a ton of smaller features, fixes and improvements.

Features

  • Generating a Rails 5.1.4 app on Ruby 2.5.0
  • Dropped asset pipeline in favor of Webpacker
  • The generated application now has a sleek, simple design based on Bootstrap
  • Employing Unpoly
  • New application model DSL shortcut crud for "create a model and a web UI with crud actions"
  • The generated application model is now a transformable e...

Setup your terminal to not scroll when there is new output

When you are scrolling up to investigate a test failure it is super annoying when the terminal scrolls back down whenever the running test outputs another line. Luckily you can disable this behavior:

  • Gnome terminal: *Edit -> Profile preferences -> Scrolling", uncheck Scroll on output
  • Terminator: Right click on terminal screen, Preferences -> Profile -> (for each profile) -> Scrolling, uncheck Scroll on output

Rails 3/4: How to add routes for specs only

If you want to have routes that are only available in tests (e.g. for testing obscure redirects), you can use the with_routing helper -- but that one destroys existing routes which may break a specs that require them to work.

To keep both "regular" and test routes, do this:

class MyApplicationController < ActionController::Base
  def show
    render text: 'Welcome to my application'
  end
end

test_routes = Proc.new do
  get '/my_application' => 'my_application#show'
end
Rails.application.routes.ev...

The Bark Blog » Testing Rails Model Plugins

Unfortunately, by default plugin tests are pretty bland. They use the plain unit test suite supplied by Ruby, and not any of the extended Rails test framework. This will leave our plugin’s test classes with no access to fixtures, database.yml configuration, or any of those nice class auto-loading features.

SSHKit 1.9.0 failure for Capistrano deploy

SSHKit 1.9.0 might fail with the following error, when trying to deploy a Rail application. Upgrading the gem to version 1.21.0 fixed the issue.

Traceback (most recent call last):
	17: from /home/user/.rbenv/versions/2.5.0/lib/ruby/gems/2.5.0/gems/sshkit-1.9.0/lib/sshkit/runners/parallel.rb:12:in `block (2 levels) in execute'
	16: from /home/user/.rbenv/versions/2.5.0/lib/ruby/gems/2.5.0/gems/sshkit-1.9.0/lib/sshkit/backends/abstract.rb:29:in `run'
	15: from /home/user/.rbenv/versions/2.5.0/lib/ruby/gems/2.5.0/gems/sshkit-1.9....

makandra/capybara-lockstep

capybara-lockstep can help you with flaky end-to-end tests:

This Ruby gem synchronizes Capybara commands with client-side JavaScript and AJAX requests. This greatly improves the stability of a full-stack integration test suite, even if that suite has timing issues.

dbconsole in Rails 3 requires the environment as the first argument

There is a bug in Rails 3's dbconsole script, which makes the following command open a database console for the development environment:

rails dbconsole -p test

You need to write this instead:

rails dbconsole test -p

Selenium: Network throttling via Chromedriver

You can throttle the network in your headless chrome via Selenium. This might be useful for debugging issues with flaky integration tests or slow page simulations.

page.driver.browser.network_conditions = {offline: false, latency: 5, download_throughput: 2 * 1024, upload_throughput: 2 * 1024}

The settings will match to the following UI component in Chrome:

Image

Were the values for the default profiles might match the values from this post:

**S...

Rails: Parsing a time in a desired timezone

Sometimes you want to have a time in a given timezone independent from you Rails timezone settings / system timezone. I usually have this use case in tests.

Example

Time.parse('2020-08-09 00:00') will return different results e.g. 2020-08-09 00:00:00 +0200 depending on the Rails timezone settings / system timezone. But in this example we always want to have the given time in UTC because that's what the API returns.

it 'returns a valid API response', vcr: true do
  expect(client.get('/users/1')).to have_attributes(
    name: 'So...

Silencing Deprecation Warnings in Rspec

If you’re testing the behavior of deprecated code in your Ruby project, the warning messages littered throughout your spec output is incredibly noisy.

You could silence all warnings with ::ActiveSupport::Deprecation.silenced = true, but you might miss out on an important warning in one of your dependencies. It’s tempting to remove the tests altogether (the code will be burned soon too, right?), but I figured out something a little nicer a little while back in Formtastic’s test suite.

How to communicate between processes in Ruby with sockets

In Ruby you can communicate between processes with sockets. This might be helpful in tests that validate parallel executions or custom finalization logic after the garbage collector. Here is an example how such an communication will look like:

require 'socket'
BUFFER_SIZE = 1024

# DGRAM has the advantage that it stops reading the pipe if the next messages starts. In case the message size is larger than the
# BUFFER_SIZE, you need to handle if you are reading another part of the current message or if you already reading the
# next mess...

Undefined method log for Selenium::WebDriver::Remote::W3C::Bridge

In case your integration tests crash with a message like below, try to upgrade Capybara to a newer version (3.35.3 was good enough). You might encounter this issue when you enabled the w3c option in Selenium.

undefined method `log' for #<Selenium::WebDriver::Remote::W3C::Bridge:0x000055995647ded0>

Your affected code might look similar to this call below and will work after the upgrade again.

GitHub Actions: Manually running a workflow

To start a workflow manually it must have a trigger called workflow_dispatch:

---
name: Tests
on:
  push:
    branches:
    - master
  pull_request:
    branches:
    - master
  workflow_dispatch:
    branches:
    - master  

In the Actions tab of your repo you can now select a workflow and press "Run Workflow".

See GitHub documentation for details.

How to install packages from newer Ubuntu releases

We're usually running Ubuntu LTS versions. Sometimes newer hardware requires packages from more recent Ubuntu releases that only come with 6 months of support. If there is really no other way, it's possible to install packages from later Ubuntu releases

Caution: Pay really close attention to what you're doing. Depending on the package, this process may require upgrading a lot of dependencies, possibly breaking the system! You really should not do this unless you've carefully calculated the impact on your system

Preparation

First,...

Upgrading Cucumber and Capybara to the latest versions available for Rails 2

Specify these gem versions in your Gemfile:

gem 'cucumber', '~> 1.3.0'
gem 'cucumber-rails', '= 0.3.2' # max version for Rails 2
gem 'capybara', '< 2' # capybara 2+ requires Rails 3
gem 'mime-types', '< 2' # dependeny of capybara
gem 'nokogiri', '< 1.6' # dependency of capybara
gem 'rubyzip', '< 1' # dependency of selenium-webdriver, rubyzip 1+ requires Ruby 1.9
gem 'cucumber_factory'
gem 'database_cleaner', '< 1'
gem 'cucumber_spinner', '~> 0.2.5'
gem 'launchy', '~> 2.1.2'

With these versions set, `...

How to check if a file is a human readable text file

Ruby's File class has a handy method binary? which checks whether a file is a binary file. This method might be telling the truth most of the time. But sometimes it doesn't, and that's what causes pain. The method is defined as follows:

# Returns whether or not +file+ is a binary file.  Note that this is
# not guaranteed to be 100% accurate.  It performs a "best guess" based
# on a simple test of the first +File.blksize+ characters.
#
# Example:
#
#   File.binary?('somefile.exe') # => true
#   File.binary?('somefile.txt') # => fal...

Minify Font Awesome fonts with webpack

Font Awesome 5 is a comprehensive solution for vector icons on your website.

Originally, Font Awesome came as an icon font (plus stylesheets), but recently it can also be used as a pure JavaScript solution (which will render icons as inline <svg> tags), or even as SVG sprites.

All solutions have their pros and cons:

Icon font:

  • little CPU load (no JavaScript)
  • fonts are relatively large
  • 1 extra HTTP request

Javascript + inline SVG:

  • higher CPU load (needs to watch the DOM via mutation observers to ad...

How to: Validate dynamic attributes / JSON in ActiveRecord

PostgreSQL and ActiveRecord have a good support for storing dynamic attributes (hashes) in columns of type JSONB. But sometimes you are missing some kind of validation or lookup possibility (with plain attributes you can use Active Record's built-in validations and have your schema.rb).

One approach about being more strict with dynamic attributes is to use JSON Schema validations. Here is an example, where a project has the dynamic attributes analytic_stats, that we can use to store analytics from an external measurement tool.

  • A g...

Show the character set and the collation of your MySQL tables

To show the collation of your tables you have to login to the MySQL console and execute SHOW TABLE STATUS FROM database;

mysql> SHOW TABLE STATUS FROM test;
+-------------+--------+---------+------------+------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+---------------------+------------+-----------------+----------+----------------+---------+
| Name        | Engine | Version | Row_format | Rows | Avg_row_length | Data_length | Max_data_length | Index_leng...