To return non-HTML responses (like XLS spreadsheets), we usually use the respond_to do |format| format.xls do # send spreadsheet end end This is often, but not always the same...
...one format checks for authorization and the other doesn't. params[:format] is only set when a user explicitly puts a .xls at the end of the URL. The format.xls...
Looking at the source code of the validates_numericality_of validator, it becomes clear that it converts the attribute in question to either an integer or float: if configuration[:only...
...any of your users as this is only broken in the most extreme case shown above...
...is a checklist I use to work on issues. For this purpose I extracted several cards related to the makandra process and ported them into a check list and refined...
...main/master branch Branch off the master with geordi branch or manually Name your branch like sort-users-by-name-73624, i.e. start with the issue id, then a shortened description...
...want some output. In Rails > 3.1 you have two methods at hand: announce and say_with_time. In the migration: class AddUserToken < ActiveRecord::Migration class User < ActiveRecod::Base; end
add_column :users, :token, :string announce "now generating tokens" User.find_in_batches do |users| say_with_time "For users ##{users.first.id} to ##{users.last.id}" do users.each do |user| user.update_attribute :token...
When a user shares your content, a snippet with title, image, link and description appears in her timeline. By default social networks will use the window title, the first image...
...the current URL and some random text snippet for this purpose. This is often not what you want. Luckily Facebook, Twitter, etc. lets you control how your content appears in...
...old to match the format created by pg_dump. The version of the PostgreSQL server doesn't matter here. For example, the official Ubuntu 20.04 sources include only PostgreSQL...
...amd64] after deb so that it reads deb [arch=amd64] https://... or deb [arch=amd64 signed-by=.... Workaround Step 2: Connect with host option The latest PostgresQL client will only...
...want to be in there. In order to reduce the chance to accidentally commit something you didn't intend, review your changes before committing. My preferred way of doing this...
...N . # Add all paths, but not their contents git add -p Git will now show you all your changes in small chunks and ask you in an interactive mode whether...
...can use ETags to allow clients to use cached responses, if your application would send the same contents as before. Besides what "actually" defines your response's contents, your application...
...probably also considers "global" conditions, like which user is signed in: class ApplicationController < ActionController::Base etag { current_user&.id } etag { current_user&.updated_at } end Under the hood, Rails generates...
$number = $length / 1px // => 13 Converting a unit the result of an addition or subtraction between two numbers of different units is expressed in the first member’s unit
...the desired unit: $duration: .21s $duration-in-milliseconds: 0ms + $duration // => 210ms An example is storing a transition duration as CSS custom property to read it from Javascript. By converting the...
PostgreSQL's Common Table Expressions (CTEs) can be used to extract sub-queries from bulky SQL statements into a temporary table to be referenced instead. This is most useful to...
...avoid ugly joins or sub-selects. CTEs can be used for SELECT, INSERT, UPDATE or DELETE. Example (from the PostgreSQL docs): WITH regional_sales AS ( SELECT region, SUM(amount) AS...
Normally, Rails handles encryption and signing of cookies, and you don't have to deal with the matter. Should you need to decrypt a session cookie manually: here is how...
...Obviously, you can only decrypt a session cookie from within the corresponding Rails application. Only the Rails application that encrypted a cookie has the secrets to decrypt it.
...you prepare your changelist properly, it directs your reviewer’s attention to areas that support your growth rather than boring style violations. When you demonstrate an appreciation for constructive criticism...
...your reviewer provides better feedback . Make others better: Your code review techniques set an example for your colleagues. Effective author practices rub off on your teammates, which makes your job...
...default order" of rows in database tables. For instance, when you paginate a result set: When using LIMIT, it is important to use an ORDER BY clause that constrains the...
...result rows into a unique order. Otherwise you will get an unpredictable subset of the query's rows. You might be asking for the tenth through twentieth rows, but tenth...
Option 0: Download from the official page (preferred) Open https://googlechromelabs.github.io/chrome-for-testing/ In Section "Stable" > chromedriver / linux64 > Download ZIP from URL Take the chromedriver binary from the ZIP file and...
...your path like this: echo "export PATH=$PATH:$HOME/bin" >> $HOME/.bash_profile Option 2: Use apt source Warning Wo no longer recommend this option. After a chrome update, the chromedriver package sometimes...
...with information from an associated table, you can JOIN the associated table into the statement. Example Let's say you have a database schema where an Employee belongs_to :department...
Now you need to backfill existing Employee records with the new department_name. Since the department's name lives in another table, you need to JOIN both tables during...
This note shows how to merge an ugly feature branch with multiple dirty WIP commits back into the master as one pretty commit. Squashing commits with git rebase
...here will destroy commit history and can go wrong. For this reason, do the squashing on a separate branch: git checkout -b squashed_feature This way, if you screw up...
Sometimes it's nice to have some coloring in your logs for better readability. You can output your logs via tail and pipe this through sed to add ANSI color...
...containing "FATAL" in red and all lines with "INFO" in green: tail -f /path/to/log | sed --unbuffered -e 's/\(.*INFO.*\)/\o033[32m\1\o033[39m/' -e 's/\(.*FATAL.*\)/\o033[31m...
The benefit of the Rails asset pipeline is that it compiles your stylesheets and javascripts to a single file, respectively. However, the consequences are startling if you don't understand...
...all your asset libraries in the same folder, which quickly becomes confusing as your set of assets grows. To overcome this, we have two different solutions. Custom solution
...text right next to the code: notes for other developers, and for your future self. You can imagine comments as post-its (or sometimes multi-sheet letters ...) on real-world...
...objects like cupboards, light switches etc. As always, with power comes responsibility. Code comments can go wrong in many ways: they may become outdated, silently move away from the code...
In long diffs, it can become impossible to spot small changes in larger blocks of moved code. This may be either a method that was moved from the top to...
...the bottom of a file, or a long test file that was split in many. Fortunately, Git offers a special highlighting mode that directs the reader's attention to relevant...
Splitting up commits makes the process of reviewing often easier, since you can create several merge requests or review every commit one by one. So when you find out that...
...refactoring along the current changes, you can use one of the following processes to split up the changes into several commits in a logical order: #1 Splitting up the last...
If you want to play music or sounds from a browser, your choice is to use either Flash or the new tag in HTML5. Each method has issues, but depending...
Can play MP3s or Wave files. Cannot play OGG Vorbis audio. Cannot reliably seek to a given position when playing VBR-encoded MP3s. HTML5 audio Is the future, but...
options.add_option(:web_socket_url, true) options.add_option(:page_load_strategy, 'none') # required for selenium-webdriver 4.27+ end Capybara::Selenium::Driver.new(app, browser: :chrome, options: options) In combination with...
...ignore' } (which we recommend setting) any unload alerts will now stay open until handled. Note Selenium-Ruby doesn't allow setting the unhandled prompt behavior to a hash yet. See...
...use heredoc to avoid endlessly long lines of code that nobody can read. Heredoc strings preserve linebreaks and can be used like this: def long_message puts(<<-EOT)
...a very long message... Sincerely, foobear EOT end <<-EOT will be somewhat of a placeholder: anything you write in the line after you used it will be its value until...