Webmock's hash_including doesn't parse query values to string

Webmocks hash_including is similar to RSpec::Mocks::ArgumentMatchers#hash_including. Be aware that hash_including (webmock v3.0.1) doesn't parse integer values to String.

Without hash including you would say:

uri = URI('http://example.com/?foo=1&bar=2')
stub_request(:get, 'example.com').with(query: {foo: 1, bar: 2})
Net::HTTP.get(uri) # ===> Success

If you only want to check if foo is present you can use hash_including:

uri = URI('http://example.com/?foo=1&bar=2')
stub_request(:get, 'example.com').with(query: hash_i...

HTTP/2 push is tougher than I thought - JakeArchibald.com

TLDR: Browser implementations of HTTP/2 push are horrible. You might end up with worse performance than without pushing. However, the article includes a great explanation of how HTTP/2 push are supposed to integrate with browser APIs.

Quickly printing data in columns on your Ruby console

Dump this method into your Ruby console to quickly print data in columns. This is helpful for e.g. comparing attributes of a set of Rails records.

def tp(objects, *method_names)
  terminal_width = `tput cols`.to_i
  cols = objects.count + 1 # Label column
  col_width = (terminal_width / cols) - 1 # Column spacing

  Array(method_names).map do |method_name|
    cells = objects.map{ |o| o.send(method_name).inspect }
    cells.unshift(method_name)

    puts cells.map{ |cell| cell.to_s.ljust(col_width) }.join ' '
  end

  nil
end

Usag...

Using ActiveRecord with threads might use more database connections than you think

Database connections are not thread-safe. That's why ActiveRecord uses a separate database connection for each thread.

For instance, the following code uses 3 database connections:

3.times do
  Thread.new do
    User.first # first database access makes a new connection
  end
end

These three connections will remain connected to the database server after the threads terminate. This only affects threads that use ActiveRecord.

You can rely on Rails' various clean-up mechanisms to release connections, as outlined below. This may...

Storing trees in databases

This card compares patterns to store trees in a relation database like MySQL or PostgreSQL. Implementation examples are for the ActiveRecord ORM used with Ruby on Rails, but the techniques can be implemented in any language or framework.

We will be using this example tree (from the acts_as_nested_set docs):

root
|
+-- Child 1
|   |
|   +-- Child 1.1
|   |
|   +-- Child 1.2
|
+-- ...

How to use Parallel to speed up building the same html partial multiple times (for different data)

The parallel-gem is quite easy to use and can speed up rendering time if you want to render the same partial multiple times (e.g. for rendering long lists of things).

Parallel supports execution using forked processes (the default), threads (mind the GVL) and Ractors (some limitations for data sharing).

If your parallelized code talks to the database, you should [ensure not to leak database connections](https://makandracards.com/makandra/45360-using-activerecord-with-threads-will-leak-database-connect...

Rendering 404s for missing images via Rails routes

When you load a dump for development, records may reference images that are not available on your machine.

Requests to those images may end up on your application, e.g. if a catch-all route is defined that leads to a controller doing some heavy lifting. On pages with lots of missing images, this slows down development response times.

You can fix that by defining a Rails route like this:

if Rails.env.development?
  scope format: true, constraints: { format: /jpg|png|gif/ } do
    get '/*anything', to: proc { [404, {}, ['']] }

...

How to disable Chrome's save password bubble for Selenium tests

When filling out forms in Selenium tests, Chrome shows the (usual) bubble, asking to store those credentials.

While the bubble does not interfere with tests, it is annoying when debugging tests. Here are two ways to disable it:

Option 1: prefs

You can set profile preferences to disable the password manager like so:

prefs = {
  'credentials_enable_service' => false,
  'profile.password_manager_enabled' => false
}

Capybara::Selenium::Driver.new(app, browser: :chrome, prefs: prefs)

Sadly, there are no command line s...

Rails: Default generators

This is a visualization of the files that will be generated by some useful rails generators. Invoke a generator from command line via rails generate GENERATOR [args] [options]. List all generators (including rails generators) with rails g -h.

generator model migration controller entry in routes.rb views tests
scaffold
resource ✔ ...

ActiveRuby

Looks like ActiveState is trying to market a new Ruby distribution for Enterprises:

ActiveRuby Enterprise Edition is designed for businesses with large Ruby deployments in essential, mission-critical applications that, when down, could cost your business in lost revenue and a damaged reputation. Deploy Ruby with confidence knowing you're using the most secure, enterprise-grade builds for the platforms that power your business. You'll get priority access to our Ruby experts for technical support and best prac...

VCR: Inspecting a request

Using VCR to record communication with remote APIs is a great way to stub requests in tests. However, you may still want to look at the request data like the payload your application sent.

Using WebMock, this is simple: Make your request (which will record/play a VCR cassette), then ask WebMock about it:

expect(WebMock).to have_requested(:post, 'http://example.com').with(body: 'yolo')

Easy peasy.

Related cards

Thinkpad: Disable Bluetooth on start-up

Add the following to /etc/rc.local:

(sleep 3 && echo disable > /proc/acpi/ibm/bluetooth)&

Bluetooth icon will be active for a few seconds, then turn gray.

Some useful vim settings

Below is a list of some VIM settings I find useful. You can add them to your .vimrc.

source $VIMRUNTIME/mswin.vim                 " adds Ctrl-X, Ctrl-C, Ctrl-V; block visual mode is now Ctrl-Q
behave mswin

set autowriteall                             " autosave all files when a buffer is closed

set backupdir=~/.temp                        " dont pollute local directory with swap file, backup files etc
set dir=~/.temp

set undofile                                 " enable persistent undo
set undodir=~/.temp

set encoding=utf-8

...

JavaScript Start-up Performance

As web developers, we know how easy it is to end up with web page bloat. But loading a webpage is much more than shipping bytes down the wire. Once the browser has downloaded our page’s scripts it then has to parse, interpret & run them. In this post, we’ll dive into this phase for JavaScript, why it might be slowing down your app’s start-up & how you can fix it.

The article author also tested 6000+ production sites for load times. Apps became interactive in 8 seconds on desktop (using cable) and 16 seconds on mobile (Moto G4 over 3G).

Never use SET GLOBAL sql_slave_skip_counter with a value higher than 1

If you have a replication error with MySQL and you know the "error" is okay (e.g. you've executed the same statement at the same time on 2 masters which sync each other), you can skip this error and continue with the replication without having to set up the slave from the ground up.

stop slave;
set global sql_slave_skip_counter = 1;
start slave;

But what if you have multiple errors which you want to skip? (e.g. you've executed multiple statement at the same time on 2 masters which sync each other)
Still do not use a value highe...

Error "undefined method last_comment"

This error message may occur when rspec gets loaded by rake, e.g. when you migrate the test database.

NoMethodError: undefined method 'last_comment' for #<Rake::Application:0x0055a617d37ad0>

Rake 11 removes a method that rspec-core < 3.4.4 depends on. To fix, lock Rake to < 11 in your Gemfile:

  gem 'rake', '< 11', # Removes a method that rspec-core < 3.4 depends on

Geordi hints

Reminder of what you can do with Geordi.

Note: If you alias Geordi to something short like g, running commands gets much faster!
Note: You only need to type the first letters of a command to run it, e.g. geordi dep will run the deploy command.

geordi deploy

Guided deployment, including push, merge, switch branches. Does nothing without confirmation.

geordi capistrano

Run something for all Capistrano environments, e.g. geordi cap deploy

geordi setup -t -d staging

When you just clon...

JSONP for Rails

The rack-contrib gem brings a JSONP middleware that just works™. Whenever a JSON request has a callback parameter, it will wrap the application's JSON response appropriately.

The project is a bit dated, but the JSONP middleware is ok.

[jruby] TruffleRuby Status, start of 2017

TruffleRuby is an experimental Ruby implementation that tries to achieve ~10x performance over MRI.

This has been on our radar for a while. They seem to have made significant progress running Rails, reducing start-up time and becoming runtime-independent of the JVM.

Also see [Running Optcarrot, a Ruby NES emulator, at 150 fps with the GUI!](https://eregon.me/blog/2016/11/28/optcarrot.htm...

How to tackle complex refactorings in big projects

Sometimes huge refactorings or refactoring of core concepts of your application are necessary for being able to meet new requirements or to keep your application maintainable on the long run. Here are some thoughts about how to approach such challenges.

Break it down

Try to break your refactoring down in different parts. Try to make tests green for each part of your refactoring as soon as possible and only move to the next big part if your tests are fixed. It's not a good idea to work for weeks or months and wait for all puzzle pieces ...

JavaScript: Don't throw synchronous exceptions from functions that return a Promise

TLDR: A function is hard to use when it sometimes returns a promise and sometimes throws an exception. When writing an async function, prefer to signal failure by returning a rejected promise.

The full story

When your function returns a promise ("async function"), try not to throw synchronous exceptions when encountering fatal errors.

So avoid this:

function foo(x) {
  if (!x) {
    throw "No x given"
  } else
    return new Promise(funct...

An Introduction to Sending HTML Email for Web Developers

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 inevitable that coding an email will be a task that gets dropped in your lap at some time 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 tables to mark up our websites.

Table of Contents

  • Introduction To Sending Email Link
  • Email List B...

CarrierWave: When your uploader generates filenames dynamically, use model.save! instead of uploader.recreate_versions!

If your Carrierwave uploader dynamically generates the filename (e.g. by incorporating a user's name), you must call model.save! after recreating versions.

uploader.recreate_versions! does not update the model with the stored filename.

Howto use ActiveRecord preload with plain SQL inner joins

Like you know from "How to tell ActiveRecord how to preload associations (either JOINs or separate queries)", you can tell ActiveRecord explicitly if it should use a LEFT OUTER JOIN or a separate query to preload associations.

Here is some special case, where a simple includes is not possible. For the diagram below we want to sort the rides by the translated name of the departure_place and the arrival_place:

![6020905239052288.png](https://makandracards.com/makandra/43252-howto-combine-custom-sql-with-preload/a...