There is a new card about how to do this with the new AWS Command Line Interface

At first you need the IAM Cli Tools.
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cURL makes a web request and shows you the response body.

You can redirect the response body to /dev/null just like for many other programs. But if you do that, cURL will display some short information about the request you are making:

$ curl http://www.example.com/ > /dev/null
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100 30865  100 30865    0     0   4793      0  0:00:06  0:00:06 --:--:-- 10199

If you wan...

Consider you have a website vhost listening to www.example.com, redirecting all incoming requests that do not talk about the configured hostname (this is often used to redirect users to http://www.example.com when entering only http://example.com/).

If you want to make a request to that site's web server without actually talking to www.example.com (e.g. because this is a load balancer's address but you want to access one specific machine), you cannot just request machine1.example.com or localhost as the above vhost will redirect...

If your application raises an error like ...
Couldn't connect to the Solr server at http://127.0.0.1:8983/solr. 500 "Lock_obtain_timed_out_SimpleFSLock(...)"

... and if your jetty.request.log contains entries such as ...
127.0.0.1 - - [13/09/2011:12:42:23 +0000] "POST /solr/update HTTP/1.1" 500 4412
127.0.0.1 - - [13/09/2011:13:37:03 +0000] "POST /solr/update HTTP/1.1" 500 4309

... you probably have a lucene-...-write.lock file lying around in your Solr data directory that is not being cleaned up properly. This causes...

When you drag a file from a Nautilus window into a terminal window, the file's path will be pasted into the terminal. This also works with multiple files.

Whenever Firefox updates, all your Cucumber features that use Selenium break. This is annoying.

In order to remedy this, version 0.5.0 of our geordi gem comes with a script that helps you create an unchanging version of Firefox for your Selenium tests. In particular, this new copy of Firefox will have the following properties:

• It won't update itself with a newer version
• It can co-exist with your regular Firefox installation (which you can update at will)
• It will use a profile separate from the one...

Selenium does not speak SSL because it uses WEBrick that doesn't. When you use Selenium for Cucumber scenarios that visit pages with SSL, they will fail.

To turn off SSL only for scenarios that are executed on WEBrick, put this method into your application controller.

def ensure_proper_protocol
  request.headers['SERVER_SOFTWARE'].andand.include?('WEBrick') || super
end

Ever wondered how Rails talks to itself in a Cucumber feature? In Rails 3 you can do it like this:

def rack_env(path)
  { "rack.input" => {},
    "PATH_INFO"=>"#{path}",
    "REQUEST_METHOD"=>"GET" }
end

request = rack_env('/users/new')
response = Rails.application.call(request)
status, headers, body = response

puts status # e.g. 200
puts headers.inspect # hash of headers
puts body.body # html of response body

Instead of Rails.application you can also call any Rack application.

If you have any class which requires access to some path methods generated by your routes. Even though you could technically include Rails.application.routes.url_helpers, this may include way too many methods and even overwrite some class methods in the worst case.

Instead, most of the time the following is advised to only make the desired methods available:

class Project
  delegate :url_helpers, to: 'Rails.application.routes'

  def project_path
    url_helpers.project_path(self)
  end
end

Just add the parameter :post to the visit method:

visit publish_entry_path, :post

Rails doesn't know which host it is running on. For generating links, it strips the hostname off the request URL, which can lead to errors when you have absolute URLs in your Cucumber tests.

If you really need to use absolute URLs somewhere, say in an email you send, either throw away the host when parsing it (e.g. body.scan(/http:\/\/[^\/]+\/([^\s"<]+)/)) or tell Webrat you're back on your site.

When the Ruby parser module of Ruby-GetText comes across a file in one of its search directories (e.g. lib/scripts/) and finds out that you are defining ActiveRecord classes inside it, it evaluates the whole file. Here is how to avoid that.

What's happening?

Let's say you have the following script which is only run once, manually, via script/runner:

# lib/scripts/doomsday.rb
class User < ActiveRecord::Base; end
User.destroy_all

In that case we ...

tl;dr: Always have your attachment path start with :rails_root/storage/#{Rails.env}#{ENV['RAILS_TEST_NUMBER']}/.

The directory where you save your Paperclip attachments should not look like this:

storage/photos/1/...
storage/photos/2/...
storage/photos/3/...
storage/attachments/1/...
storage/attachments/2/...

The problem with this is that multiple environments (at least development and test) will share the same directory structure. This will cause you pain eventually. Files will get overwritten and...

If you get the error "413 Request Entity Too Large" from Nginx client_max_body_size is too low (default is client_max_body_size=1m).

This can happen for example during file upload.

Don't simply test for the presence of the magic Paperclip attribute, it will return a paperclip Attachment object and thus always be true:

- if user.photo.present? # always true
  = image_tag(user.photo.url)

Use #exists? instead:

- if user.photo.exists?
  = image_tag(user.photo.url)

Under the same origin policy, a web page served from server1.example.com cannot normally connect to or communicate with a server other than server1.example.com. An exception is the HTML <script> element. Taking advantage of the open policy for <script> elements, some pages use them to retrieve Javascript code that operates on dynamically-generated JSON-formatted data from other origins. This usage pattern is known as JSONP. Requests for JSONP retrieve not JSON, but arbitrary JavaScript code.

Cross-Origin Resource Sharing (CORS) is a browser technology specification, which defines ways for a web service to provide interfaces for sandboxed scripts coming from a different domain under same origin policy. CORS is a modern alternative to the JSONP pattern. While JSONP supports only the GET request method, CORS also supports other types of HTTP requests. Using CORS enables a web programmer to use regular XMLHttpRequest which supports better error handling than JSONP. On the other hand, JSONP works on legacy browsers that do not have C...

Code example for implementing Cross-Origin Resource Sharing (CORS) in Rails.

When you need to zip up files in Ruby, use zipruby.

sudo gem install zipruby

You can add existing files, add files from strings and even add directories.
Example usage:

require 'zipruby'
cars = %w[audi bmw mercedes]

zipfile = Tempfile.new('my.zip', 'tmp')
Zip::Archive.open(zipfile.path, Zip::CREATE) do |zip|
  zip.add_file '/tmp/me.txt'
  zip.add_dir 'cars' 

  cars.each do |car|
    zip.add_buffer "cars/#{car}.txt", "This #{car} is mine!" 
  end
end

Credits go to winebarrel for the Ruby bin...

To offer files for download, use send_file.

def download(file)
  send_file file.path, :disposition => 'attachment'
end

Note that a send_file replaces the default :render action.

Resque comes with its own dashboard (Resque server) that you can mount inside your Rails 3 application with

#config/routes.rb:

require 'resque/server'

My::Application.routes.draw do
  # ...

  mount Resque::Server => '/resque'
end

Unfortunately, since this bypasses the filters in your ApplicationController, everyone can access this dashboard now (unless you have some Rack-based authentication in place, like Devise).

If you're using ...

This note describes how to kick a user out of a Rails application after she hasn't requested an action for a while. Note that this is different from deleting sessions some time after the last login, which is the default.

Also note that this is probably a bad idea. Most sites keep sessions alive forever because having to sign in again and again is quite inconvenient for users and makes your conversion rates go down the toilet. [The Clearance default is to keep sessions around for one year](https://makandracards.com/makandra/701-when-sessio...

When you create a temporary file (e.g. to store a generated Excel sheet) and try to send it to the browser from a controller, it won't work by default. Take this controller action:

class FoosController < ApplicationController
  def download
    file = Tempfile.new('foo')
    file.puts 'foo'
    file.close
    send_file file.path
  end
end

Accessing this controller action will usually raise a 404 not found in the browser and the Apache log will say:

The given path was above the root path: xsendfile: ...