Pexels: Free stock photos
You can find great stock photos on pexels.com.
All pictures are free for personal and commercial use without attribution, and may be modified.
Detecting if a Ruby gem is loaded
Detect if a gem has been activated
A gem is activated if it is either in the current bundle (Gemfile.lock
), or if you have manually activated it using Kernel#gem
(old-school).
To detect if e.g. activerecord
has been activated:
if Gem.loaded_specs.has_key?('activerecord')
# ActiveRecord was activated
end
Detect if a particular gem version has been activated
To detect if e.g. activerecord
ma...
Ubuntu Mate: Get rid of F12 drop-down terminal
To get your F12
key back for other shortcuts, stop Tilda:
killall tilda
To prevent Tilda from starting on boot you can remove it
sudo apt-get remove tilda
or disable auto start:
- Go to Mate Control Center > Startup Applications
- uncheck "Tilda"
makandra/gemika: Helpers for testing Ruby gems
We have released a new library Gemika to help test a gem against multiple versions of Ruby, gem dependencies and database types.
Here's what Gemika can give your test's development setup (all features are opt-in):
- Test one codebase against multiple sets of gem dependency sets (e.g. Rails 4.2, Rails 5.0).
- Test one codebase against multiple Ruby versions (e.g. Ruby 2.1.8, Ruby 2.3.1).
- Test one codebase against multiple database types (currently MySQL or PostgreSQL).
- Compute a matrix of all possib...
Fix "libmysqlclient.so.20: cannot open shared object file: No such file or directory"
This error can be caused by the mysql2 gem under mysterious circumstances. You need to remove it with gem uninstall mysql2
and then reinstall it (or just run bundle
).
gem pristine mysql2
will not be enough.
Sass: How to convert an RGBA color to its RGB look-alike
Say you have an RGBA color that you need as a non-transparent color because of reasons.
Basically, this is possible. Just understand that you will convert your RGBA color for exactly one base background color as you are giving up transparency.
Most likely, your background is white, so you'll use #fff
as that for examples below.
Simple approach
When your know the RGBA color's base RGB color (e.g. your brand color that you RGBA'd for some hover effect), you can simply use the mix
function instead of rgba
.
Before:
backgroun...
VCR fails if the same request is triggered multiple times
Same requests are recorded only once in vcr. Replaying a test fails, if you trigger the same request multiple times. The error message is somehow confusing, as your cassette contains the request:
An HTTP request has been made that VCR does not know how to handle
If you want to allow to match a request multiple times, you need to configure this explicit with allow_playback_repeats: true. Some exa...
Heads up: "localhost" may be IPv6 on new linuxes
I've encountered a Ubuntu 16.04 today, where localhost
resolved to ::1
instead of 127.0.0.1
.
This will not usually make a difference, but could be relevant for firewall policies.
What every coder should know about gamma
Good article about what "gamma correction" means for color processing, and what "sRGB" actually means.
You probably do not need to know this for web development, but it's an interesting read.
Migrations are versioned in Rails 5 | BigBinary Blog
Rails 5 migration classes look like this now:
class CreateUsers < ActiveRecord::Migration[5.0]
Mind the [5.0]
at the end.
They do this to evolve the ActiveRecord::Migration API without breaking your historical migrations in db/migrate
.
List of handy Chrome plugins
These are Chrome plugins that proved useful at makandra. Each is the best-in-class.
Dimensions
: Auto-measure distances by moving your mouse.
Google Analytics Debugger
: See details about Google Analytics events that you trigger on a page. Useful for debugging on production sites.
[JSON Formatter](https://chrome.google.com/webstore/detail/json-forma...
Bundler returns different error codes depending on what went wrong
When you are calling Bundler from your shell scripts, you might find it useful that a failed bundle
call returns a different error code depending on the type of problem.
A list of error codes can be found here.
Measuring sql query time of a piece of code using ActiveSupport::Notifications
ActiveSupport::Notifications provides an instrumentation API for Ruby. It is used throughout rails to publish instrumentation events that include information about each part of a request/response cycle.
Have a look at your application log file - yes, those are those events. The cool thing is that you can subscribe to those events.
There is also a convenience method that allows you to subscribe to those events only for the time of executing a block of code. Thus you can capture all sql queries that are triggered when executing your block....
How to disable material design in Google Chrome
A few releases back, Chrome started using a Material Design UI on desktop. If you don't like it (on some window managers or GTK themes it's ugly), you can disable it.
- Visit chrome://flags/
- Search (
Ctrl
+F
) for "Material Design" - Switch to "Non-Material"
- Restart Chrome
Chrome's default theme should now be pretty again.
Hack of the day: One-liner to run all changed Cucumber features
Similar to our snippet that runs all Cucumber features matching a given string, the following will run all modified or new Cucumber features by looking at your git status:
git status --short | grep -v '^ D ' | grep '.feature' | sed 's/.. //' | tr '\n' ' ' | xargs geordi cucumber
If you want to know what each of the above commands does, see [explainshell](http://explainshell.com/explain?cmd=git+status+--short+%7C+grep+-v+%27%5E+D+%27+%7C+grep+%27.feature%27+%7C+sed+%27s%2F..+%2F%2F%27+%7C+tr+%27%5Cn%27+%27+%27+%7C...
How to use Haml in your helpers
You know those helper methods that just render some HTML but look weird because of content_tag
s all over the place? You could also use Haml instead.
Example
Consider the following helper.
def greeting
message = ''.html_safe
message << 'Welcome to '
message << content_tag(:span, Rails.env, class: 'greeting--location')
content_tag :div, message, class: 'greeting'
end
That looks clumsy and is hard to read.
Wouldn't it be nicer to say something like this?
def greeting
render_haml <<-HAML
...
Isolate Side Effects in Ruby
In this article, we’ll look at what side effects are, why they are problematic despite being necessary, and how to isolate them to minimise their drawbacks.
Minidusen: Low-tech record filtering with LIKE queries
We have a new gem Minidusen which extracts Dusen's query parsing and LIKE
query functionality.
Minidusen can no longer index text in MySQL FULLTEXT columns, which was hardly used and didn't always help performance due to the cost of reindexing.
Minidusen is currently compatible with MySQL, PostgreSQL, Rails 3.2, Rails 4.2 and Rails 5.0.
Basic Usage
Our example will be a simple address book:
class Contact < ActiveRecord::Base
validates_presence_of :name, :street, :city, :e...
We are no longer maintaining Dusen
If you were using Dusen for its query parsing and LIKE queries, we recommend to migrate to Minidusen, which extracts those parts from Dusen. Minidusen is compatible with MySQL, PostgreSQL and Rails 3.2, 4.2 and 5.0.
If you are looking for a full text indexing solution, we recommend to use PostgreSQL with pg_search.
How to tidy up your Git mess
Git is hard: screwing up is easy, and figuring out how to fix your mistakes is fucking impossible. Git documentation has this chicken and egg problem where you can't search for how to get yourself out of a mess, unless you already know the name of the thing you need to know about in order to fix your problem.
Maybe this flowchart may be of help...
Javascript: Read params from url
There is no build in functionally in jQuery and Prototype to extract params from a url.
-
You can use this library (not tested): jquery-deparam
-
Use Unpoly and the following code snippet
Geordi 1.5.1 released
- Improve
geordi cucumber
: Only attempt @solo run when the specified files contain the @solo tag, skip @solo run if any filename is passed with a line number (e.g.features/example.feature:3
) - Improve
geordi deploy
: Find stages by their prefix (e.g.s
-> staging,m
-> makandra), bundle if needed, check the selected stage exists - Improve
geordi server
: Takes port as argument (e.g.geordi ser 3001
), option--public
(-P
) starts the server with-b 0.0.0.0
to make it accessible from other machines in the local network, e.g. ...
Capistrano: exclude custom bundle groups for production deploy
Capistrano is by default configured to exclude the gems of the groups development
and test
when deploying to the stages production
and staging
. Whenever you create custom groups in your Gemfile
, make sure to exclude these, if they should not be deployed to the servers. The gems of these groups might not be loaded by rails, however, the deployment process will take longer as the gems will be downloaded and installed to the server.
e.g. to exclude the groups cucumber
and deploy
, add the following to `config/deploy/production.rb...
ClockPicker: Android-style time picker for Bootstrap
ClockPicker is a JavaScript and Bootstrap implementation of an Android-style time picker which looks and feels great.
Unfortunately, it is no longer maintained.