Right now I have:
#models = ActiveRecord::Base.send(:subclasses)
But I get this in the log:
DEPRECATION WARNING: subclasses is deprecated and will be removed from Rails 3.0 (use descendants instead). (called from send at /Users/*******/m3p0/app/controllers/roles_controller.rb:50)
What should I replace :subclasses with?
It is in the warning, it says use descendants instead.
ActiveRecord::Base.send(:descendants)
Also, these methods are publicly available so you don't need to use the .send syntax, you can call it explicitly.
ActiveRecord::Base.descendants
Here is the output from one of my apps:
ruby-1.9.2-p180 :001 > ActiveRecord::Base.subclasses
=> [Achievement(id: integer...
ruby-1.9.2-p180 :003 > ActiveRecord::Base.descendants
=> [Achievement(id: integer...
Related
If we have an Active Record database say Users
User.find(id) works as expected:
But so does User.find('id~')
Also User.find('id~gibberish')
Is this a vulnerability or flaw of ActiveRecord?
How do I handle such requests appropriately?
This should help clear some things up, it is not ActiveRecord, it's Ruby's to_i method that you're seeing.
2.2.1 :001 > '11'.to_i
=> 11
2.2.1 :002 > '11~'.to_i
=> 11
2.2.1 :003 > '11~gibberish'.to_i
=> 11
This is not a vulnerability nor a flaw. If you're worried about input like this, I'd ask for an example where you think it could cause you harm.
Additionally if you'd like to be super defensive, use Integer(
2.2.1 :004 > Integer('11~gibberish')
ArgumentError: invalid value for Integer(): "11~gibberish"
2.2.1 :005 > Integer('11')
=> 11
What is the difference between Ruby’s Hash and ActiveSupport’s HashWithIndifferentAccess? Which is the best for dynamic hashes?
Below is the simple example that will show you difference between simple ruby hash & a "ActiveSupport::HashWithIndifferentAccess"
HashWithIndifferentAccess allows us to access hash key as a symbol or string
Simple Ruby Hash
$ irb
2.2.1 :001 > hash = {a: 1, b:2}
=> {:a=>1, :b=>2}
2.2.1 :002 > hash[:a]
=> 1
2.2.1 :003 > hash["a"]
=> nil
ActiveSupport::HashWithIndifferentAccess
2.2.1 :006 > hash = ActiveSupport::HashWithIndifferentAccess.new(a: 1, b:2)
NameError: uninitialized constant ActiveSupport
from (irb):6
from /home/synerzip/.rvm/rubies/ruby-2.2.1/bin/irb:11:in `<main>'
2.2.1 :007 > require 'active_support/core_ext/hash/indifferent_access'
=> true
2.2.1 :008 > hash = ActiveSupport::HashWithIndifferentAccess.new(a: 1, b:2)
=> {"a"=>1, "b"=>2}
2.2.1 :009 > hash[:a]
=> 1
2.2.1 :010 > hash["a"]
=> 1
class HashWithIndifferentAccess is inherited from ruby "Hash" & above special behavior is added in it.
In Ruby Hash:
hash[:key]
hash["key"]
are different. In HashWithIndifferentAccess as the name suggests, you can access key either way.
Quoting official documentation to this:
Implements a hash where keys :foo and "foo" are considered to be the
same.
and
Internally symbols are mapped to strings when used as keys in the
entire writing interface (calling []=, merge, etc). This mapping
belongs to the public interface. For example, given:
hash = ActiveSupport::HashWithIndifferentAccess.new(a: 1)
You are
guaranteed that the key is returned as a string:
hash.keys # => ["a"]
In Rails I often do this:
Model.last(5).first
This retrieves element last-5.
Is there a built-in way of doing this?
The more common way is offset()
Model.offset(5).last
Edit (for lazy people):
1.8.7 :001 > User.first.id
=> 1
1.8.7 :002 > User.last.id
=> 143455
1.8.7 :003 > User.offset(5).last.id
=> 143450
In app/services, I have some classes, as Notification::Finder and Notification::Builder.
They are placed as app/services/notification/builder.rb and app/services/notification/finder.rb.
There is also the Notification class as a model, at app/models/notification.rb
The autoload_path is configurated as in config.autoload_paths += %W(#{config.root}/app/services)
When I try to load Finder, it works:
Loading development environment (Rails 3.2.9)
[1] pry(main)> Notification::Finder
=> Notification::Finder
But when I try the Builder, I get a problem with the rails autoloading:
Loading development environment (Rails 3.2.9)
[1] pry(main)> Notification::Builder
=> ActiveRecord::Associations::Builder
It just ignores the namespace I've used when the constant name (Builder) has already been defined by other namespace, and gets the ActiveRecord::Associations::Builder instead.
Is this the expected behavior, or a rails bug?
Going more detailed, the const_missing method at activesupport/dependencies.rb receives a const_name 'Builder', and nesting.inspect => 'nil'.
Curious that when I use constantize, it resolves as expected:
Loading development environment (Rails 3.2.9)
[1] pry(main)> 'Notification::Builder'.constantize
=> Notification::Builder
( Rails issue at github: https://github.com/rails/rails/issues/8726 )
ActiveRecord::Associations::Builder is a module in Rails. If you have a Notification::Builder, you can ask it its class:
>> Notification::Builder
=> ActiveRecord::Associations::Builder
>> Notification::Builder.class
=> Module
>> Notification::Builder.ancestors
=> [ActiveRecord::Associations::Builder]
Is this expected behavior?
Yes
OK, so... what choices do you have?
You can use a different term than Builder. Like Factory. or Notification::NotificationBuilder
More info:
* http://www.rubydoc.info/docs/rails/3.1.1/ActiveRecord/Associations/Builder/Association
* http://apidock.com/rails/ActiveRecord/Associations/Builder
This problem exists because you are using an ActiveRecord model as a namespace. I created a gist with some experimentation until I saw the root cause.
ActiveRecord models include the ActiveRecord::Associations module. Since you can get to a constant when including a module the Builder constant defined within Associations is now also reachable through the AR model. You will get this behavior with every class defined in the modules, which are included into an AR model:
1.9.3-p194 :010 > Post.ancestors
=> [Post(id: integer, title: string, published_at: datetime, created_at: datetime, updated_at: datetime), Post::GeneratedFeatureMethods, #<Module:0x007fec74dc33a0>, ActiveRecord::Base, ActiveRecord::Core, ActiveRecord::Store, ActiveRecord::Serialization, ActiveModel::Serializers::Xml, ActiveModel::Serializers::JSON, ActiveModel::Serialization, ActiveRecord::Reflection, ActiveRecord::Transactions, ActiveRecord::Aggregations, ActiveRecord::NestedAttributes, ActiveRecord::AutosaveAssociation, ActiveModel::SecurePassword, ActiveRecord::Associations, ActiveRecord::Timestamp, ActiveModel::Validations::Callbacks, ActiveRecord::Callbacks, ActiveRecord::AttributeMethods::Serialization, ActiveRecord::AttributeMethods::Dirty, ActiveModel::Dirty, ActiveRecord::AttributeMethods::TimeZoneConversion, ActiveRecord::AttributeMethods::PrimaryKey, ActiveRecord::AttributeMethods::Query, ActiveRecord::AttributeMethods::BeforeTypeCast, ActiveRecord::AttributeMethods::Write, ActiveRecord::AttributeMethods::Read, ActiveRecord::AttributeMethods, ActiveModel::AttributeMethods, ActiveRecord::Locking::Pessimistic, ActiveRecord::Locking::Optimistic, ActiveRecord::CounterCache, ActiveRecord::Validations, ActiveModel::Validations::HelperMethods, ActiveSupport::Callbacks, ActiveModel::Validations, ActiveRecord::Integration, ActiveModel::Conversion, ActiveRecord::AttributeAssignment, ActiveModel::ForbiddenAttributesProtection, ActiveModel::DeprecatedMassAssignmentSecurity, ActiveRecord::Sanitization, ActiveRecord::Scoping::Named, ActiveRecord::Scoping::Default, ActiveRecord::Scoping, ActiveRecord::Inheritance, ActiveRecord::ModelSchema, ActiveRecord::ReadonlyAttributes, ActiveRecord::Persistence, Object, PP::ObjectMixin, ActiveSupport::Dependencies::Loadable, V8::Conversion::Object, JSON::Ext::Generator::GeneratorMethods::Object, Kernel, BasicObject]
A possible solution is to use a module as a namespace. For example module Notifications.
I have an Image, which contains carrierwave uploads:
Image.find(:first).image.url #=> "/uploads/image/4d90/display_foo.jpg"
In my view, I want to find the absolute url for this. Appending the root_url results in a double /.
root_url + image.url #=> http://localhost:3000//uploads/image/4d90/display_foo.jpg
I cannot use url_for (that I know of), because that either allows passing a path, or a list of options to identify the resource and the :only_path option. Since I do't have a resource that can be identified trough "controller"+"action" I cannot use the :only_path option.
url_for(image.url, :only_path => true) #=> wrong amount of parameters, 2 for 1
What would be the cleanest and best way to create a path into a full url in Rails3?
You can also set CarrierWave's asset_host config setting like this:
# config/initializers/carrierwave.rb
CarrierWave.configure do |config|
config.storage = :file
config.asset_host = ActionController::Base.asset_host
end
This ^ tells CarrierWave to use your app's config.action_controller.asset_host setting, which can be defined in one of your config/envrionments/[environment].rb files. See here for more info.
Or set it explicitly:
config.asset_host = 'http://example.com'
Restart your app, and you're good to go - no helper methods required.
* I'm using Rails 3.2 and CarrierWave 0.7.1
try path method
Image.find(:first).image.path
UPD
request.host + Image.find(:first).image.url
and you can wrap it as a helper to DRY it forever
request.protocol + request.host_with_port + Image.find(:first).image.url
Another simple method to use is URI.parse, in your case would be
require 'uri'
(URI.parse(root_url) + image.url).to_s
and some examples:
1.9.2p320 :001 > require 'uri'
=> true
1.9.2p320 :002 > a = "http://asdf.com/hello"
=> "http://asdf.com/hello"
1.9.2p320 :003 > b = "/world/hello"
=> "/world/hello"
1.9.2p320 :004 > c = "world"
=> "world"
1.9.2p320 :005 > d = "http://asdf.com/ccc/bbb"
=> "http://asdf.com/ccc/bbb"
1.9.2p320 :006 > e = "http://newurl.com"
=> "http://newurl.com"
1.9.2p320 :007 > (URI.parse(a)+b).to_s
=> "http://asdf.com/world/hello"
1.9.2p320 :008 > (URI.parse(a)+c).to_s
=> "http://asdf.com/world"
1.9.2p320 :009 > (URI.parse(a)+d).to_s
=> "http://asdf.com/ccc/bbb"
1.9.2p320 :010 > (URI.parse(a)+e).to_s
=> "http://newurl.com"
Just taking floor's answer and providing the helper:
# Use with the same arguments as image_tag. Returns the same, except including
# a full path in the src URL. Useful for templates that will be rendered into
# emails etc.
def absolute_image_tag(*args)
raw(image_tag(*args).sub /src="(.*?)"/, "src=\"#{request.protocol}#{request.host_with_port}" + '\1"')
end
There's quite a bunch of answers here. However, I didn't like any of them since all of them rely on me to remember to explicitly add the port, protocol etc. I find this to be the most elegant way of doing this:
full_url = URI( root_url )
full_url.path = Image.first.image.url
# Or maybe you want a link to some asset, like I did:
# full_url.path = image_path("whatevar.jpg")
full_url.to_s
And what is the best thing about it is that we can easily change just one thing and no matter what thing that might be you always do it the same way. Say if you wanted to drop the protocol and and use the The Protocol-relative URL, do this before the final conversion to string.
full_url.scheme = nil
Yay, now I have a way of converting my asset image urls to protocol relative urls that I can use on a code snippet that others might want to add on their site and they'll work regardless of the protocol they use on their site (providing that your site supports either protocol).
I used default_url_options, because request is not available in mailer and avoided duplicating hostname in config.action_controller.asset_host if haven't specified it before.
config.asset_host = ActionDispatch::Http::URL.url_for(ActionMailer::Base.default_url_options)
You can't refer to request object in an email, so how about:
def image_url(*args)
raw(image_tag(*args).sub /src="(.*?)"/, "src=\"//#{ActionMailer::Base.default_url_options[:protocol]}#{ActionMailer::Base.default_url_options[:host]}" + '\1"')
end
You can actually easily get this done by
root_url[0..-2] + image.url
I agree it doesn't look too good, but gets the job done.. :)
I found this trick to avoid double slash:
URI.join(root_url, image.url)