| class DatabaseController < ApplicationController | |
| def database_dump | |
| database = Rails.configuration.database_configuration[Rails.env]["database"] | |
| send_file_headers!(:type => 'application/octet-stream', :filename => "#{database}_#{Time.now.to_s(:human)}.backup") | |
| pipe = IO.popen("pg_dump '#{database}' -F c") | |
| stream = response.stream | |
| while (line = pipe.gets) | |
| stream.write line | |
| sleep 0.0001 # HACK: Prevent server instance from sleeping forever if client disconnects during download |
Eric Bidelman has documented some of the common workflows possible with headless Chrome over in https://developers.google.com/web/updates/2017/04/headless-chrome.
If you're looking at this in 2016 and beyond, I strongly recommend investigating real headless Chrome: https://chromium.googlesource.com/chromium/src/+/lkgr/headless/README.md
Windows and Mac users might find using Justin Ribeiro's Docker setup useful here while full support for these platforms is being worked out.
| <button id="copy" class="btn">Copy</button> |
| class EpisodeSearch | |
| attr_reader :ability, :options | |
| delegate :sanitize, to: Episode | |
| def initialize(ability, options = {}) | |
| @ability = ability | |
| @options = options.dup | |
| end | |
| def tag |
In researching topics for RailsCasts I often read code in Rails and other gems. This is a great exercise to do. Not only will you pick up some coding tips, but it can help you better understand what makes code readable.
A common practice to organize code in gems is to divide it into modules. When this is done extensively I find it becomes very difficult to read. Before I explain further, a quick detour on instance_eval.
You can find instance_eval used in many DSLs: from routes to state machines. Here's an example from Thinking Sphinx.
class Article < ActiveRecord::Base
https://github.com/jnicklas/carrierwave
This example will create an uploader that will upload a file stored in a model Model. The file will be stored locally in development and test environment and will use Amazon S3 in production.
First add the gems.
| class TasksController < ApplicationController | |
| def update | |
| tracker = TaskTracker.new(@task) | |
| if @task.update_attributes(params[:task]) | |
| TaskPusher.new(tracker, socket_id).push_changes | |
| TaskMailSender.new(tracker, current_user).deliver_email | |
| # success response | |
| else | |
| # failure respond | |
| end |
| module Abilities | |
| def self.ability_for(user) | |
| if user.admin? | |
| AdminAbility.new(user) | |
| else user | |
| MemberAbility.new(user) | |
| else | |
| GuestAbility.new | |
| end | |
| end |
This helper has finally been moved into a gem called nav_lynx!
https://github.com/vigetlabs/nav_lynx
http://rubygems.org/gems/nav_lynx
Thanks to @brianjlandau and @reagent for getting that set up and tested!
| <!DOCTYPE html> | |
| <html lang="en" style="overflow: hidden"> | |
| <body style="overflow:hidden"> | |
| <head> | |
| <!-- You need to include jquery & FBSDK--> | |
| </head> | |
| <body> | |
| <div id="fb-root"></div> | |
| <script> | |
| window.fbAsyncInit = function() { |