1.
The Grapes of Rapid
Michael Bleigh, RubyConf 2010

2.
@mbleigh
@intridea

3.
confask.heroku.com

4.
This is not the
talk I wanted.

5.
CDD

6.
Conference
Driven
Development

7.
Deliver
Promise
Me

8.
Motivation

9.
Ruby makes
hard things easy

10.
But APIs still
aren’t easy

11.
APIs in Rails are
too entangled

12.
APIs in Sinatra
are too manual

13.
Why can’t APIs
have their own
framework?

14.
#newtwitter

15.
Grape

16.
Generalized
Rapid
API
Erector

17.
Something that
sounds like API...
ape grapegravy

18.
High Level

19.
Built for ease of
development.

20.
Sinatra-inspired.

21.
Just works.

22.
What does it do?

23.
What does it
do now?

24.
Basics

25.
require 'grape'
class MyAPI < Grape::API
get 'hello' do
{:hello => 'world'}
end
end
GET /hello
{“hello”:”world”}

26.
JSON
Serialization

27.
•Look for #serializable_hash
•Look for #to_json
•Then tries to encode the object directly
•Other formats coming soon
With Returned Value...

28.
Prefixing

29.
class MyAPI < Grape::API
prefix 'api'
get 'hello' do
{:hello => 'world'}
end
end
GET /hello
404 Not Found
GET /api/hello
{“hello”:”world”}

30.
Versioning

31.
class MyAPI < Grape::API
prefix 'api'
version 'v1'
get 'hello' do
{:version => version}
end
end
GET /api/v1/hello
{“version”:”v1”}
GET /api/v2/hello
404 API Version
Not Found

32.
Namespacing

33.
class MyAPI < Grape::API
namespace :admin do
namespace 'metrics' do
get do
{:clicks => Click.count}
end
get '/:date' do
{:clicks => Click.for_date(params[:date]).count}
end
end
end
end
GET /admin/metrics
{“clicks”:235343}
GET /admin/metrics/2010-11-13
{“clicks”:5392}

34.
Stackable
Configuration

35.
Basic Auth

36.
class MyAPI < Grape::API
get 'open' do
"Hello."
end
namespace :admin do
http_basic do |u,p|
u == 'admin' && p == ENV['ADMIN_PASSWORD']
end
namespace 'metrics' do
get do
{:clicks => Click.count}
end
end
end
end
GET /admin/metrics
401 Unauthorized
admin:somepassword
GET /admin/metrics
{“clicks”:235343}

37.
Helpers

38.
class MyAPI < Grape::API
helpers do
def current_user
User.find_by_token(params[:token])
end
end
get '/me' do
current_user
end
end
GET /me?token=12ab312df
{“screen_name”:”mbleigh”}

39.
Erroring

40.
class MyAPI < Grape::API
helpers do
def current_user
@current_user ||= User.find_by_token(params[:token])
end
end
get '/me' do
error!("401 Unauthorized", 401) unless current_user
current_user
end
end
GET /me?token=invalidtoken
401 Unauthorized

41.
What will
it do soon?

42.
Documentation
Generation

43.
Content
Negotiation

44.
OAuth 1.0/2.0

45.
Multiple Files

46.
Plugin System

47.
Vaporware

48.
Streaming APIs

49.
PubSubHubBub

50.
Presenters

51.
Rate Limiting

52.
Internal API

53.
ConfAsk:
Grape In Action

54.
Questions?
gem install grape
github.com/intridea/grape