1. Enter the App Era
with Ruby on Rails
@matteocollina

2. RubyDay.it
15 June 2012
www.rubyday.it

3. Matteo Collina
Software Engineer
@matteocollina
matteocollina.com

4. www.mavigex.com
www.wemobi.it

5. How is built an App?
http://www.flickr.com/photos/dschulian/3173331821/

6. Code
Icons by Fasticon

7. Code Run
Icons by Fasticon

8. Code Run Server
Icons by Fasticon

9. Code Run Server
Icons by Fasticon

10. Code Run Server
Icons by Fasticon

11. Code I need to
serve
Run Server
my data to
Web and Mobile Apps
Icons by Fasticon

12. We need an API

13. We need an API
Who has APIs?

14. Who has APIs?

15. Who has APIs?

16. Who has APIs?
And many many others..

17. We will develop an API

18. We need to be fast!
http://www.flickr.com/photos/oneaustin/1261907803

19. We have just
twenty minutes
http://www.flickr.com/photos/oneaustin/1261907803

20. What do we
want to build? http://www.flickr.com/photos/oberazzi/318947873/

21. Another tool for nerds?
http://www.flickr.com/photos/eyesontheroad/2260731457/

22. Another Todo List?
http://www.flickr.com/photos/eyesontheroad/2260731457/

23. Enter MCDo.
http://github.com/mcollina/mcdo

24. Enter MCDo.
The First Todo List
delivered as
a REST API

25. The First Todo List
delivered as
a REST API

26. Signup API
http://github.com/mcollina/mcdo

27. Signup API
Feature: Signup API
As a MCDO developer
In order to develop apps
I want to register new users
Scenario: Succesful signup
When I call "/users.json" in POST with:
"""
{
"user": {
"email": "hello@abc.org",
"password": "abcde",
"password_confirmation": "abcde"
}
}
"""
Then the JSON should be:
"""
{
"id": 1,
"email": "hello@abc.org"
}
"""

28. Signup API
Scenario: signup fails with a wrong password_confirmation
When I call "/users.json" in POST with:
"""
{
"user": {
"email": "hello@abc.org",
"password": "abcde",
"password_confirmation": "abcde1"
}
}
"""
Then the JSON should be:
"""
{
"errors": { "password": ["doesn't match confirmation"] }
}
"""

29. How?

30. How?
Ruby on Rails
Cucumber
RSpec
JSON-spec

31. How?
Ruby on Rails
Let’s see some code!
Cucumber
RSpec
JSON-spec

32. Login API
http://github.com/mcollina/mcdo

33. Login API
Feature: Login API
As a MCDO developer
In order to develop apps
I want to login with an existing user
Background:
Given there is the following user:
| email | password | password_confirmation |
| abcd@org.it | aa | aa |
Scenario: Succesful login
When I call "/session.json" in POST with:
"""
{
"email": "abcd@org.it",
"password": "aa"
}
"""
Then the JSON should be:
"""
{
"status": "authenticated"
}
"""

34. Login API
Scenario: Failed login
When I call "/session.json" in POST with:
"""
{
"email": "abcd@org.it",
"password": "bb"
}
"""
Then the JSON should be:
"""
{
"status": "not authenticated"
}
"""

35. Login API
Scenario: Validating an active session
Given I call "/session.json" in POST with:
"""
{
"email": "abcd@org.it",
"password": "aa"
}
"""
When I call "/session.json" in GET
Then the JSON should be:
"""
{
"status": "authenticated"
}
"""

36. Login API
Scenario: Validating an active session
Given I call "/session.json" in POST with:
"""
{
"email": "abcd@org.it",
"password": "aa"
}
Let’s see some code!
"""
When I call "/session.json" in GET
Then the JSON should be:
"""
{
"status": "authenticated"
}
"""

37. Lists API
http://github.com/mcollina/mcdo

38. Lists API
Feature: Lists API
As a MCDO developer
In order to develop apps
I want to manage a user's lists
Background:
Given I login succesfully with user "aaa@abc.org"
Scenario: Default lists
When I call "/lists.json" in GET
Then the JSON should be:
"""
{
"lists": [{
"id": 1,
"name": "Personal",
"link": "http://www.example.com/lists/1",
"items_link": "http://www.example.com/lists/1/items"
}]
}
"""

39. Lists API
Scenario: Creating a list
When I call "/lists.json" in POST with:
"""
{
"list": {
"name": "foobar"
}
}
"""
Then the JSON should be:
"""
{
"name": "foobar",
"items_link": "http://www.example.com/lists/1/items"
}
"""

40. Lists API
Scenario: Creating a list should add it to the index
Given I call "/lists.json" in POST with:
"""
{
"list": {
"name": "foobar"
}
}
"""
When I call "/lists.json" in GET
Then the JSON should be:
"""
{
"lists": [{
"id": 2,
"name": "foobar",
"link": "http://www.example.com/lists/2",
"items_link": "http://www.example.com/lists/2/items"
}, {
"id": 1,
"name": "Personal",
"link": "http://www.example.com/lists/1",
"items_link": "http://www.example.com/lists/1/items"
}]
}
"""

41. Lists API
Scenario: Removing a list (and the index is empty)
Given I call "/lists/1.json" in DELETE
When I call "/lists.json"
Then the JSON should be:
"""
{
"lists": []
}
"""
Scenario: Updating a list's name
When I call "/lists/1.json" in PUT with:
"""
{
"list": {
"name": "foobar"
}
}
"""
Then the JSON should be:
"""
{
"name": "foobar",
"items_link": "http://www.example.com/lists/1/items"
}
"""

42. Lists API
Scenario: Removing a list (and the index is empty)
Given I call "/lists/1.json" in DELETE
When I call "/lists.json"
Then the JSON should be:
"""
{
"lists": []
}
"""
Let’s see some code!
Scenario: Updating a list's name
When I call "/lists/1.json" in PUT with:
"""
{
"list": {
"name": "foobar"
}
}
"""
Then the JSON should be:
"""
{
"name": "foobar",
"items_link": "http://www.example.com/lists/1/items"
}
"""

43. Items API
http://github.com/mcollina/mcdo

44. Items API
Feature: Manage a list's items
As a developer
In order to manipulate the list's item
I want to access them through APIs
Background:
Given I login succesfully with user "aaa@abc.org"
Scenario: Default items
When I call "/lists/1/items.json" in GET
Then the JSON should be:
"""
{
"items": [{
"name": "Insert your items!",
"position": 0
}],
"list_link": "http://www.example.com/lists/1"
}
"""

45. Items API
Scenario: Moving an element to the top
Given I call "/lists/1/items.json" in POST with:
...
And I call "/lists/1/items.json" in POST with:
...
When I call "/lists/1/items/2/move.json" in PUT with:
"""
{
"position": 0
}
"""
Then the JSON should be:
"""
{
"items": [{
"name": "b",
"position": 0
}, {
"name": "Insert your items!",
"position": 1
}, {
"name": "c",
"position": 2
}],
"list_link": "http://www.example.com/lists/1"
}
"""

46. Items API
Scenario: Moving an element to the top
Given I call "/lists/1/items.json" in POST with:
...
And I call "/lists/1/items.json" in POST with:
...
When I call "/lists/1/items/2/move.json" in PUT with:
"""
{
"position": 0
}
Let’s see some code!
"""
Then the JSON should be:
"""
{
"items": [{
"name": "b",
"position": 0
}, {
"name": "Insert your items!",
"position": 1
}, {
"name": "c",
"position": 2
}],
"list_link": "http://www.example.com/lists/1"
}
"""

47. Do we need
an admin panel?

48. Do we need
an admin panel?

49. Do we need
an admin panel?
Put in your Gemfile:
gem 'activeadmin'
gem 'meta_search', '>= 1.1.0.pre'
Then run:
$ bundle install
$ rails g active_admin:install
$ rails g active_admin:resource users
$ rails g active_admin:resource lists
$ rails g active_admin:resource items
$ rake db:migrate

50. Do we need
an admin panel?
Put in your Gemfile:
Let’s see some code!
gem 'activeadmin'
gem 'meta_search', '>= 1.1.0.pre'
Then run:
$ bundle install
$ rails g active_admin:install
$ rails g active_admin:resource users
$ rails g active_admin:resource lists
$ rails g active_admin:resource items
$ rake db:migrate

51. Build a JS App!

52. Build a JS App!
Backbone.js: MVC in the browser
Rails asset pipeline concatenate
and minifies our JS automatically
We can even write our app in
CoffeeScript: it works out of the box.

53. Build a JS App!
Backbone.js: MVC in the browser
to Rails asset pipeline concatenate
the code.. again?
and minifies our JS automatically
We can even write our app in
CoffeeScript: it works out of the box.

54. http://www.flickr.com/photos/oneaustin/1261907803

55. We are late,
the #codemotion
crew are kicking me out
http://www.flickr.com/photos/oneaustin/1261907803

56. TL;DR
http://www.flickr.com/photos/evilaugust/3307382858

57. TL;DR
Mobile Apps need an API
Ruby on Rails is good for writing APIs
You can build nice admin interfaces
with ActiveAdmin
You can craft Javascript Apps easily
using the asset pipeline.

58. RubyDay.it
15 June 2012
www.rubyday.it

59. Any Questions?

60. Thank You!