Share
Embed
Slide 1
Slide 1 text
Fast Rails APIs
Railsberry
Kraków
April 19th, 2012
Monday, April 23, 12
Slide 2
Slide 2 text
ms
Monday, April 23, 12
Slide 3
Slide 3 text
Monday, April 23, 12
Slide 4
Slide 4 text
Monday, April 23, 12
Slide 5
Slide 5 text
Monday, April 23, 12
Slide 6
Slide 6 text
Interpreted
Dynamic typing
Object-Oriented
Monday, April 23, 12
Slide 7
Slide 7 text
Speed is a feature
Monday, April 23, 12
Slide 8
Slide 8 text
Request
Router
Controller
Response
Monday, April 23, 12
Slide 9
Slide 9 text
Request
Router
Controller
Response
Monday, April 23, 12
Slide 10
Slide 10 text
ActionController::Metal
Monday, April 23, 12
Slide 11
Slide 11 text
class NormalController < ActionController::Base
def index
@messages = Message.paginate(:page => params[:page])
respond_to do |format|
format.json { render :json => @messages }
end
end
end
Monday, April 23, 12
Slide 12
Slide 12 text
class MetalController < ActionController::Metal
def index
@messages = Message.paginate(:page => params[:page])
self.response_body = @messages.to_json
self.status = 200
self.content_type = 'application/json'
end
end
Monday, April 23, 12
Slide 13
Slide 13 text
0
175
350
525
700
Requests/second
Normal Light
Monday, April 23, 12
Slide 14
Slide 14 text
M V C
Monday, April 23, 12
Slide 15
Slide 15 text
render :json => @posts
Monday, April 23, 12
Slide 16
Slide 16 text
@posts.to_json
Monday, April 23, 12
Slide 17
Slide 17 text
M C
Monday, April 23, 12
Slide 18
Slide 18 text
Representer pattern
Monday, April 23, 12
Slide 19
Slide 19 text
apotonick/roar
josevalim/active_model_serializers
Monday, April 23, 12
Slide 20
Slide 20 text
representer
Monday, April 23, 12
Slide 21
Slide 21 text
Representer == Object Oriented View
Monday, April 23, 12
Slide 22
Slide 22 text
app/representers/message_representer.rb
Monday, April 23, 12
Slide 23
Slide 23 text
class MessageRepresenter < Representer::Base
namespace :message
attributes :id, :title, :body
end
Monday, April 23, 12
Slide 24
Slide 24 text
class MessageRepresenter < Representer::Base
namespace :message
attributes :id, :title, :body
fields :images
aggregate :images, :id do |ids, representer|
# This is imaginary code!! <3
RemoteApiClient.find_images(ids).group_by(&:message_id)
end
def images(message)
self.aggregated_images[message['id']]
end
end
Monday, April 23, 12
Slide 25
Slide 25 text
class MessageRepresenter < Representer::Base
namespace :message
attributes :id, :title, :body
belongs_to :user
has_many :attachments
end
Monday, April 23, 12
Slide 26
Slide 26 text
@messages = Message.limit(50)
representer = MessageRepresenter.new(@messages)
representer.render(:json)
Monday, April 23, 12
Slide 27
Slide 27 text
@messages.represent(:json)
Monday, April 23, 12
Slide 28
Slide 28 text
{
"message": {
"id": 1,
"title": "OMG YES",
"body": "best thing ever"
}
}
Monday, April 23, 12
Slide 29
Slide 29 text
Control
Monday, April 23, 12
Slide 30
Slide 30 text
class MessageRepresenter < Representer::Base
namespace :message
attributes :id, :title, :body
belongs_to :user
has_many :attachments
end
class SimpleMessageRepresenter < Representer::Base
namespace :post
attributes :id, :title, :body
end
Monday, April 23, 12
Slide 31
Slide 31 text
Testability
Monday, April 23, 12
Slide 32
Slide 32 text
describe MessageRepresenter do
subject do
MessageRepresenter.new([])
end
describe "#render" do
it "renders to json" do
subject.render(:json).should == '[]'
end
end
end
Monday, April 23, 12
Slide 33
Slide 33 text
Speed
Monday, April 23, 12
Slide 34
Slide 34 text
Benchmarking: simple to_json
Average: 26ms
Benchmarking: active model serializer
Average: 18ms
Benchmarking: simple represent
Average: 5ms
50 messages
with user and one attachment
Monday, April 23, 12
Slide 35
Slide 35 text
Average (ms)
5
18
26
to_json Serializers Representers
50 messages
with user and one attachment
Monday, April 23, 12
Slide 36
Slide 36 text
Talk is cheap, show me the code
Linus Torvalds
Monday, April 23, 12
Slide 37
Slide 37 text
github.com/futuresimple/representer
Monday, April 23, 12
Slide 38
Slide 38 text
Monday, April 23, 12