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What's RPC?

In distributed computing, a remote procedure call (RPC) is when a computer program causes a procedure (this is what it differs from REST) to execute in another address space (commonly on another computer on a shared network), which is coded as if it were a normal (local) procedure call, without the programmer explicitly coding the details for the remote interaction.

There are multiple implementation of RPC: ONC RPC, JSON-RPC, XML-RPC, gRPC, SOAP, etc.

How RPC works?

1. The client calls the client stub. The call is a local procedure call, with parameters pushed on to the stack in the normal way.
2. The client stub packs the parameters into a message and makes a system call to send the message. Packing the parameters is called marshalling.

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git credential-osxkeychain erase
host=github.com
protocol=https

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##Jekyll Installation

1. Make a new directory for your blog

mkdir my-awesome-blog
cd my-awesome-blog

2. Create your .ruby-gemset and .ruby-version

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##Rails Submit button I18n way

en:
  helpers:
    submit:
      create: "Make New %{name}%"
      user:
        create: "Register"
 update: "Update Profile"

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Rails Active Record Query

INNER JOIN

Category.joins(:posts)

# SELECT categories.* FROM categories INNER JOIN posts ON posts.category_id = categories.id

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The markup

<div id="parent">
  <a id="child">Click here please</a>
</div>

Instead of binding event this way this way

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##Capybara - Wait for ajax to complete

def wait_for_ajax
  Timeout.timeout(Capybara.default_wait_time) do
    loop do
      active = page.evaluate_script('jQuery.active')
      break if active == 0
    end
 end

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class UrlValidator < ActiveModel::EachValidator
  def validate_each(record, attribute, value)
    record.errors[attribute] << (options[:message] || "must be a valid URL") unless url_valid?(value)    
  end

  # a URL may be technically well-formed but may 
  # not actually be valid, so this checks for both.
  def url_valid?(url)
 url = URI.parse(url) rescue false

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Rails Admin field configuration

rails_admin do
  list do
    field :customfield do
      def value
        bindings[:object].your_method
      end
    end
 end

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In your logged_in_controller.rb

class LoggedInController < ApplicationController
  before_filter :authenticate_user!
end

In your logged_in_controller_spec.rb