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INSIDE RAILS
The Lifecycle of a Response
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https://skylight.io/r/railsconf
Don’t struggle to learn why your app is slow.
Get answers with Skylight.
DO THE
ANSWER DANCE.
SKYLIGHT
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app/controllers/hello_controller.rb
Terminal
$
Trying 34.194.84.73...
Connected to ec2-34-194-84-73.compute-1.amazonaws.com.
Escape character is ‘^]’.
>
telnet 34.194.84.73 80
Picture: Masai Mara Wildlife / Matt Scobel / CC BY 3.0
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app/controllers/hello_controller.rb
class SafariController < ActionController::Base
def hello
# ...do stuff here...
render plain: 'Hello World'
end
end
app/controllers/safari_controller.rb
app/controllers/hello_controller.rb
Terminal
$
Trying 34.194.84.73...
Connected to ec2-34-194-84-73.compute-1.amazonaws.com.
Escape character is ‘^]’.
>
telnet 34.194.84.73 80
GET /safari HTTP/1.1
> Host: skylight.io
>
Picture: Masai Mara Wildlife / Matt Scobel / CC BY 3.0
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app/controllers/hello_controller.rb
Terminal
$
Trying 34.194.84.73...
Connected to ec2-34-194-84-73.compute-1.amazonaws.com.
Escape character is ‘^]’.
>
telnet 34.194.84.73 80
GET /safari HTTP/1.1
> Host: skylight.io
>
< HTTP/1.1 200 OK
< Content-Type: text/plain
< Content-Length: 11
< Date: Thu, 25 Apr 2019 18:52:54 GMT
<
< Hello World
app/controllers/hello_controller.rb
class SafariController < ActionController::Base
def hello
# ...do stuff here...
render plain: 'Hello World'
end
end
app/controllers/safari_controller.rb
Picture: Three Elephants in Early Morning / Yu Miyawaki / CC BY 3.0
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HELLO WORLD!
http://skylight.io/safari
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app/controllers/hello_controller.rb
http://skylight.io/safari
Roar Savanna
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Ok…..?
Hey, I have a request for you to handle.
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Sounds good.
It’s a GET request for /safari, Host header is skylight.io
200 OK. Content type is text/plain, body is “Roar Savanna”.
Hey, I have a request for you to handle.
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app/controllers/hello_controller.rb
http://skylight.io/safari
app/controllers/hello_controller.rb
Terminal
$
Trying 34.194.84.73...
Connected to ec2-34-194-84-73.compute-1.amazonaws.com.
Escape character is ‘^]’.
>
telnet 34.194.84.73 80
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app/controllers/hello_controller.rb
http://skylight.io/safari
app/controllers/hello_controller.rb
Terminal
$
Trying 34.194.84.73...
Connected to ec2-34-194-84-73.compute-1.amazonaws.com.
Escape character is ‘^]’.
>
telnet 34.194.84.73 80
GET /safari HTTP/1.1
> Host: skylight.io
>
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app/controllers/hello_controller.rb
http://skylight.io/safari
app/controllers/hello_controller.rb
Terminal
$
Trying 34.194.84.73...
Connected to ec2-34-194-84-73.compute-1.amazonaws.com.
Escape character is ‘^]’.
>
telnet 34.194.84.73 80
< HTTP/1.1 200 OK
< Content-Type: text/plain
< Content-Length: 12
< Date: Thu, 25 Apr 2019 18:52:54 GMT
<
< Roar Savanna
GET /safari HTTP/1.1
> Host: skylight.io
>
Roar Savanna
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handwave handwave
Check out last year's talk for more info!
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RACK
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No content
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app/controllers/hello_controller.rb
http://skylight.io/safari
app/controllers/hello_controller.rb
env = {
'REQUEST_METHOD' => 'GET',
'PATH_INFO' => ‘/safari',
'HTTP_HOST' => 'skylight.io',
# ...
}
server.rb
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app/controllers/hello_controller.rb
http://skylight.io/safari
app/controllers/hello_controller.rb
env = {
'REQUEST_METHOD' => 'GET',
'PATH_INFO' => ‘/safari',
'HTTP_HOST' => 'skylight.io',
# ...
}
app.call(env)
server.rb
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app/controllers/hello_controller.rb
http://skylight.io/safari
app/controllers/hello_controller.rb
env = {
'REQUEST_METHOD' => 'GET',
'PATH_INFO' => ‘/safari',
'HTTP_HOST' => 'skylight.io',
# ...
}
app.call(env)
server.rb
handwave handwave
Check out last year's talk for more info!
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app/controllers/hello_controller.rb
http://skylight.io/safari
app/controllers/hello_controller.rb
env = {
'REQUEST_METHOD' => 'GET',
'PATH_INFO' => ‘/safari',
'HTTP_HOST' => 'skylight.io',
# ...
}
app.call(env)
server.rb
app/controllers/hello_controller.rb
class SafariController < ActionController::Base
def hello
# Get it? A savanna is a type of plain...
render plain: 'Roar Savanna'
end
end
app/controllers/safari_controller.rb
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app/controllers/hello_controller.rb
http://skylight.io/safari
app/controllers/hello_controller.rb
env = {
'REQUEST_METHOD' => 'GET',
'PATH_INFO' => ‘/safari',
'HTTP_HOST' => 'skylight.io',
# ...
}
status, headers, body = app.call(env)
status # => 200
headers # => { 'Content-Type' => 'text/plain' }
body # => [‘Roar Savanna’]
server.rb
1
2
3
The Response Array
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app/controllers/hello_controller.rb
http://skylight.io/safari
Roar Savanna
app/controllers/hello_controller.rb
< HTTP/1.1 200 OK
< Content-Type: text/plain
< Content-Length: 12
< Date: Thu, 25 Apr 2019 18:52:54 GMT
<
< Roar Savanna
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app/controllers/hello_controller.rb
http://skylight.io/safari
Roar Savanna
app/controllers/hello_controller.rb
< HTTP/1.1 200 OK
< Content-Type: text/plain
< Content-Length: 12
< Date: Thu, 25 Apr 2019 18:52:54 GMT
<
< Roar Savanna
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No content
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app/controllers/hello_controller.rb
env = {
'REQUEST_METHOD' => 'GET',
'PATH_INFO' => ‘/safari',
'HTTP_HOST' => 'skylight.io',
# ...
}
status, headers, body = app.call(env)
status # => 200
headers # => { 'Content-Type' => 'text/plain' }
body # => [‘Roar Savanna’]
server.rb
1
The Response Array
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1xx —
2xx —
3xx —
4xx —
5xx —
STATUS CODES
Informational
Success!!
Redirection
Client Error
Server Error
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Here’s a GET request for /safari, Host header is skylight.io
OMG I DID IT! Roar Savanna!
Huh?
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Great, I can render that.
Here’s a GET request for /safari, Host header is skylight.io
200 OK; Roar Savanna
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Should I index the page at /safari ?
500 Internal Server Error
OK, I’ll be back later!
…
How about now?
200 OK; Roar Savanna
Great! I’ve indexed it.
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1xx —
2xx —
3xx —
4xx —
5xx —
STATUS CODES
Informational
Success!!
Redirection
Client Error
Server Error
PRO-TIP!
Learn a lot more about
status codes by going to
httpstatuses.com
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app/controllers/hello_controller.rb
class SafariController < ApplicationController
def eat_hippo
consume_hippo if @current_user.lion?
head :no_content # 204
end
end
app/controllers/safari_controller.rb
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app/controllers/hello_controller.rb
class SafariController < ApplicationController
def eat_hippo
consume_hippo if @current_user.lion?
head :no_content # 204
end
end
app/controllers/safari_controller.rb
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app/controllers/hello_controller.rb
class SafariController < ApplicationController
def eat_hippo
consume_hippo if @current_user.lion?
head :no_content # 204
end
end
app/controllers/safari_controller.rb
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app/controllers/hello_controller.rb
class SafariController < ApplicationController
def eat_hippo
consume_hippo if @current_user.lion?
head :no_content # 204
end
end
app/controllers/safari_controller.rb
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app/controllers/hello_controller.rb
class SafariController < ApplicationController
def eat_hippo
consume_hippo if @current_user.lion?
head :no_content # 204
end
end
app/controllers/safari_controller.rb
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app/controllers/hello_controller.rb
class SafariController < ApplicationController
before_action { @hippo = Hippo.first }
before_action { redirect_to oasis_url if dry_season? }
def find_hippo
render :hippo
end
end
app/controllers/safari_controller.rb
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app/controllers/hello_controller.rb
class SafariController < ApplicationController
before_action { @hippo = Hippo.first }
before_action { redirect_to oasis_url if dry_season? }
def find_hippo
render :hippo
end
end
app/controllers/safari_controller.rb
app/controllers/hello_controller.rb
< HTTP/1.1 302 Found
< Location: https://www.skylight.io/oasis
< Content-Type: text/plain
< Date: Thu, 25 Apr 2019 18:52:54 GMT
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No content
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app/controllers/hello_controller.rb
class SafariController < ApplicationController
before_action { @hippo = Hippo.first }
def find_hippo
redirect_to oasis_url, status: :moved_permanently
end
end
app/controllers/safari_controller.rb
app/controllers/hello_controller.rb
< HTTP/1.1 301 Moved Permanently
< Location: https://www.skylight.io/oasis
< Content-Type: text/plain
< Date: Thu, 25 Apr 2019 18:52:54 GMT
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app/controllers/hello_controller.rb
Rails.application.routes.draw do
get '/find-hippo', to: redirect('/oasis')
end
config/routes.rb
app/controllers/hello_controller.rb
< HTTP/1.1 301 Moved Permanently
< Location: https://www.skylight.io/oasis
< Content-Type: text/plain
< Date: Thu, 25 Apr 2019 18:52:54 GMT
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DANGER!
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app/controllers/hello_controller.rb
class SafariController < ApplicationController
before_action { @hippo = Hippo.first }
def find_hippo
redirect_to oasis_url if dry_season?
render :hippo
end
end
app/controllers/safari_controller.rb
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app/controllers/hello_controller.rb
class SafariController < ApplicationController
before_action { @hippo = Hippo.first }
def find_hippo
redirect_to oasis_url if dry_season?
render :hippo
end
end
app/controllers/safari_controller.rb
http://skylight.io/find-hippo
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app/controllers/hello_controller.rb
class SafariController < ApplicationController
before_action { @hippo = Hippo.first }
before_action { redirect_to oasis_url if dry_season? }
def find_hippo
render :hippo
end
end
app/controllers/safari_controller.rb
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Here’s a GET request for /safari, Host header is skylight.io
200 OK; Roar Savanna
Great, I can render that.
Wait…I need more information.
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Here’s a GET request for /safari, Host header is skylight.io
200 OK; Roar Savanna
Great, I can render that.
Wait…I need more information.
Oh yeah. It’s a plain text response.
Oh! OK!
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app/controllers/hello_controller.rb
env = {
'REQUEST_METHOD' => 'GET',
'PATH_INFO' => ‘/safari',
'HTTP_HOST' => 'skylight.io',
# ...
}
status, headers, body = app.call(env)
status # => 200
headers # => { 'Content-Type' => 'text/plain' }
body # => [‘Roar Savanna’]
server.rb
1
2 The Response Array
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app/controllers/hello_controller.rb
< HTTP/1.1 302 Found
< Content-Type: text/plain
< Location: https://www.skylight.io/oasis
< Date: Thu, 25 Apr 2019 18:52:54 GMT
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app/controllers/hello_controller.rb
< HTTP/1.1 200 OK
< Content-Type: text/plain
< Content-Length: 12
< Set-Cookie: _safari_session=some-token;
< Date: Thu, 25 Apr 2019 18:52:54 GMT
<
< Roar Savanna
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app/controllers/hello_controller.rb
< HTTP/1.1 200 OK
< Content-Type: text/plain
< Content-Length: 12
< Set-Cookie: _safari_session=some-token;
< Date: Thu, 25 Apr 2019 18:52:54 GMT
<
< Roar Savanna
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app/controllers/hello_controller.rb
< HTTP/1.1 200 OK
< Content-Type: text/plain
< Content-Length: 12
< Set-Cookie: _safari_session=some-token;
< Date: Thu, 25 Apr 2019 18:52:54 GMT
<
< Roar Savanna
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app/controllers/hello_controller.rb
< HTTP/1.1 200 OK
< Content-Type: text/plain
< Content-Length: 12
< Set-Cookie: _safari_session=some-token;
< Date: Thu, 25 Apr 2019 18:52:54 GMT
<
< Roar Savanna
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app/controllers/hello_controller.rb
response.headers['HEADER NAME'] = 'header value'
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Here’s a GET request for /safari, Host header is skylight.io
…
200 OK; Roar Savanna
Thanks!
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Here’s a GET request for /safari, Host header is skylight.io
200 OK; Roar Savanna
Here’s a GET request for /safari, Host header is skylight.io
Just use the last 200
Nice!
Thanks!
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app/controllers/hello_controller.rb
class SafariController < ApplicationController
before_action { @hippo = Hippo.first }
def find_hippo
render :hippo
end
end
app/controllers/safari_controller.rb
PRO-TIP!
Turn on caching in
development by running
rails dev:cache
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HIPPOS ARE BIG
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app/controllers/hello_controller.rb
class SafariController < ApplicationController
before_action { @hippo = Hippo.first }
def find_hippo
http_cache_forever { render :hippo }
end
end
app/controllers/safari_controller.rb
app/controllers/hello_controller.rb
< HTTP/1.1 200 OK
< Content-Type: text/html
< Cache-Control: max-age=3155695200, private
< Date: Thu, 25 Apr 2019 18:52:54 GMT
<
< …
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app/controllers/hello_controller.rb
class SafariController < ApplicationController
before_action { @hippo = Hippo.first }
def find_hippo
http_cache_forever { render :hippo }
end
end
app/controllers/safari_controller.rb
app/controllers/hello_controller.rb
< HTTP/1.1 200 OK
< Content-Type: text/html
< Cache-Control: max-age=3155695200, private
< Date: Thu, 25 Apr 2019 18:52:54 GMT
<
< …
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app/controllers/hello_controller.rb
class SafariController < ApplicationController
before_action { @hippo = Hippo.first }
def find_hippo
http_cache_forever(public: true) { render :hippo }
end
end
app/controllers/safari_controller.rb
app/controllers/hello_controller.rb
< HTTP/1.1 200 OK
< Content-Type: text/html
< Cache-Control: max-age=3155695200, public
< Date: Thu, 25 Apr 2019 18:52:54 GMT
<
< …
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app/controllers/hello_controller.rb
<%= image_tag "hippo.png" %>
app/views/safari/hippo.html.erb
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app/controllers/hello_controller.rb
<%= image_tag "hippo.png" %>
app/views/safari/hippo.html.erb
app/controllers/hello_controller.rb
http://skylight.io/find-hippo
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app/controllers/hello_controller.rb
<%= image_tag "hippo.png" %>
app/views/safari/hippo.html.erb
app/controllers/hello_controller.rb
http://skylight.io/find-hippo
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app/controllers/hello_controller.rb
<%= image_tag "hippo.png" %>
app/views/safari/hippo.html.erb
app/controllers/hello_controller.rb
http://skylight.io/find-hippo
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app/controllers/hello_controller.rb
class SafariController < ApplicationController
before_action { @hippo = Hippo.first }
def find_hippo
http_cache_forever { render :hippo }
end
end
app/controllers/safari_controller.rb
app/controllers/hello_controller.rb
< HTTP/1.1 200 OK
< Content-Type: text/html
< Cache-Control: max-age=3155695200, private
< Date: Thu, 25 Apr 2019 18:52:54 GMT
<
< …
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app/controllers/hello_controller.rb
class SafariController < ApplicationController
before_action { @hippo = Hippo.first }
def find_hippo
expires_in 1.hour
render :hippo
end
end
app/controllers/safari_controller.rb
app/controllers/hello_controller.rb
< HTTP/1.1 200 OK
< Content-Type: text/html
< Cache-Control: max-age=3600, private
< Date: Thu, 25 Apr 2019 18:52:54 GMT
<
< …
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app/controllers/hello_controller.rb
class SafariController < ApplicationController
before_action { @hippo = Hippo.first }
def find_hippo
expires_in 1.hour
render :hippo
end
end
app/controllers/safari_controller.rb
app/controllers/hello_controller.rb
< HTTP/1.1 200 OK
< Content-Type: text/html
< Cache-Control: max-age=3600, private
< Date: Thu, 25 Apr 2019 18:52:54 GMT
<
< …
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app/controllers/hello_controller.rb
class SafariController < ApplicationController
before_action { @hippo = Hippo.first }
def find_hippo
render :hippo
end
end
app/controllers/safari_controller.rb
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app/controllers/hello_controller.rb
class SafariController < ApplicationController
before_action { @hippo = Hippo.first }
def find_hippo
render :hippo
end
end
app/controllers/safari_controller.rb
app/controllers/hello_controller.rb
< HTTP/1.1 200 OK
< Content-Type: text/html
< Cache-Control: max-age=0, private, must-revalidate
< Date: Thu, 25 Apr 2019 18:52:54 GMT
<
< …
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app/controllers/hello_controller.rb
class SafariController < ApplicationController
before_action { @hippo = Hippo.first }
def find_hippo
render :hippo
end
end
app/controllers/safari_controller.rb
app/controllers/hello_controller.rb
< HTTP/1.1 200 OK
< Content-Type: text/html
< Cache-Control: max-age=0, private, must-revalidate
< Date: Thu, 25 Apr 2019 18:52:54 GMT
<
< …
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app/controllers/hello_controller.rb
class SafariController < ApplicationController
before_action { @hippo = Hippo.first }
def find_hippo
render :hippo
end
end
app/controllers/safari_controller.rb
app/controllers/hello_controller.rb
Safari
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app/controllers/hello_controller.rb
# a simplified Rack::ETag
module Rack
class ETag
def initialize(app)
@app = app
end
def call(env)
status, headers, body = @app.call(env)
if status == 200
digest = digest_body(body)
headers[Etag] = %(W/"#{digest}")
end
[status, headers, body]
end
private
#...
end
end
rack/lib/rack/etag.rb
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app/controllers/hello_controller.rb
# a simplified Rack::ETag
module Rack
class ETag
def initialize(app)
@app = app
end
def call(env)
status, headers, body = @app.call(env)
if status == 200
digest = digest_body(body)
headers[Etag] = %(W/"#{digest}")
end
[status, headers, body]
end
private
#...
end
end
rack/lib/rack/etag.rb
app/controllers/hello_controller.rb
< HTTP/1.1 200 OK
< Content-Type: text/html
< Cache-Control: max-age=0, private, must-revalidate
< ETag: W/“48a7e47309e0ec54e32df3a272094025"
< Date: Thu, 25 Apr 2019 18:52:54 GMT
<
< …
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app/controllers/hello_controller.rb
< HTTP/1.1 200 OK
< Content-Type: text/html
< Cache-Control: max-age=0, private, must-revalidate
< ETag: W/“48a7e47309e0ec54e32df3a272094025"
< Date: Thu, 25 Apr 2019 18:52:54 GMT
<
< …
app/controllers/hello_controller.rb
> GET /find-hippo HTTP/1.1
> Host: skylight.io
> If-None-Match: W/"48a7e47309e0ec54e32df3a272094025"
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app/controllers/hello_controller.rb
class SafariController < ApplicationController
before_action { @hippo = Hippo.first }
def find_hippo
render :hippo
end
end
app/controllers/safari_controller.rb
app/controllers/hello_controller.rb
Safari
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app/controllers/hello_controller.rb
# a simplified Rack::ETag
module Rack
class ETag
def initialize(app)
@app = app
end
def call(env)
status, headers, body = @app.call(env)
if status == 200
digest = digest_body(body)
headers[Etag] = %(W/"#{digest}")
end
[status, headers, body]
end
private
#...
end
end
rack/lib/rack/etag.rb
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app/controllers/hello_controller.rb
# a simplified Rack::ETag
module Rack
class ETag
def initialize(app)
@app = app
end
def call(env)
status, headers, body = @app.call(env)
if status == 200
digest = digest_body(body)
headers[Etag] = %(W/"#{digest}")
end
[status, headers, body]
end
private
#...
end
end
rack/lib/rack/etag.rb
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app/controllers/hello_controller.rb
# a simplified Rack::ETag
module Rack
class ETag
def initialize(app)
@app = app
end
def call(env)
status, headers, body = @app.call(env)
if status == 200
digest = digest_body(body)
headers[Etag] = %(W/"#{digest}")
end
[status, headers, body]
end
private
#...
end
end
rack/lib/rack/etag.rb
app/controllers/hello_controller.rb
< HTTP/1.1 200 OK
< Content-Type: text/html
< Cache-Control: max-age=0, private, must-revalidate
< ETag: W/“48a7e47309e0ec54e32df3a272094025"
< Date: Thu, 25 Apr 2019 18:52:54 GMT
<
< …
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app/controllers/hello_controller.rb
# a simplified Rack::ConditionalGet
module Rack
class ConditionalGet
def initialize(app)
@app = app
end
def call(env)
status, headers, body = @app.call(env)
if status == 200 && etag_matches?
status = 304
body = []
end
[status, headers, body]
end
private
def etag_matches?
headers['ETag'] == env['HTTP_IF_NONE_MATCH']
end
end
end
rack/lib/rack/conditional_get.rb
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app/controllers/hello_controller.rb
# a simplified Rack::ConditionalGet
module Rack
class ConditionalGet
def initialize(app)
@app = app
end
def call(env)
status, headers, body = @app.call(env)
if status == 200 && etag_matches?
status = 304
body = []
end
[status, headers, body]
end
private
def etag_matches?
headers['ETag'] == env['HTTP_IF_NONE_MATCH']
end
end
end
rack/lib/rack/conditional_get.rb
app/controllers/hello_controller.rb
< HTTP/1.1 304 Not Modified
< Cache-Control: max-age=0, private, must-revalidate
< ETag: W/“48a7e47309e0ec54e32df3a272094025”
< Content-Type: text/html
< Date: Thu, 25 Apr 2019 18:52:54 GMT
<
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app/controllers/hello_controller.rb
# a simplified Rack::ConditionalGet
module Rack
class ConditionalGet
def initialize(app)
@app = app
end
def call(env)
status, headers, body = @app.call(env)
if status == 200 && etag_matches?
status = 304
body = []
end
[status, headers, body]
end
private
def etag_matches?
headers['ETag'] == env['HTTP_IF_NONE_MATCH']
end
end
end
rack/lib/rack/conditional_get.rb
app/controllers/hello_controller.rb
< HTTP/1.1 200 OK
< Cache-Control: max-age=0, private, must-revalidate
< ETag: W/“48a7e47309e0ec54e32df3a272094025”
< Content-Type: text/html
< Date: Thu, 25 Apr 2019 18:52:54 GMT
<
< …
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No content
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app/controllers/hello_controller.rb
class SafariController < ApplicationController
before_action { @hippo = Hippo.first }
def find_hippo
render :hippo if stale?(@hippo)
end
end
app/controllers/safari_controller.rb
app/controllers/hello_controller.rb
< HTTP/1.1 200 OK
< Content-Type: text/html
< Cache-Control: max-age=0, private, must-revalidate
< ETag: W/“48a7e47309e0ec54e32df3a272094025"
< Date: Thu, 25 Apr 2019 18:52:54 GMT
<
< …
app/controllers/hello_controller.rb
< HTTP/1.1 200 OK
< Content-Type: text/html
< Cache-Control: max-age=0, private, must-revalidate
< ETag: W/"60bee75b8031cda7761a332685151766"
< Date: Thu, 25 Apr 2019 18:52:54 GMT
<
< …
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app/controllers/hello_controller.rb
Safari
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app/controllers/hello_controller.rb
"hippo/1-20071224150000"
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app/controllers/hello_controller.rb
class SafariController < ApplicationController
before_action { @hippo = Hippo.first }
def find_hippo
render :hippo if stale?(@hippo)
end
end
app/controllers/safari_controller.rb
app/controllers/hello_controller.rb
< HTTP/1.1 200 OK
< Content-Type: text/html
< Cache-Control: max-age=0, private, must-revalidate
< ETag: W/"60bee75b8031cda7761a332685151766"
< Date: Thu, 25 Apr 2019 18:52:54 GMT
<
< …
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app/controllers/hello_controller.rb
class SafariController < ApplicationController
before_action { @hippo = Hippo.first }
def find_hippo
response.headers["Cache-Control"] = "no-store"
render :hippo
end
end
app/controllers/safari_controller.rb
app/controllers/hello_controller.rb
< HTTP/1.1 200 OK
< Content-Type: text/html
< Cache-Control: no-store
< Date: Thu, 25 Apr 2019 18:52:54 GMT
<
< …
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app/controllers/hello_controller.rb
class SafariController < ApplicationController
before_action { @hippo = Hippo.first }
def find_hippo
response.headers["Cache-Control"] = "no-store"
render :hippo
end
end
app/controllers/safari_controller.rb
app/controllers/hello_controller.rb
< HTTP/1.1 200 OK
< Content-Type: text/html
< Cache-Control: no-store
< Date: Thu, 25 Apr 2019 18:52:54 GMT
<
< …
no-store ≠ no-cache
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THE RESPONSE BODY
and finally…
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app/controllers/hello_controller.rb
env = {
'REQUEST_METHOD' => 'GET',
'PATH_INFO' => ‘/safari',
'HTTP_HOST' => 'skylight.io',
# ...
}
status, headers, body = app.call(env)
status # => 200
headers # => { 'Content-Type' => 'text/plain' }
body # => [‘Roar Savanna’]
server.rb
1
2
3
The Response Array
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app/controllers/hello_controller.rb
class SafariController < ApplicationController
before_action { @hippo = Hippo.first }
def find_hippo
render :hippo
end
end
app/controllers/safari_controller.rb
app/controllers/hello_controller.rb
Safari
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app/controllers/hello_controller.rb
< HTTP/1.1 200 OK
< Content-Type: text/html
< Date: Thu, 25 Apr 2019 18:52:54 GMT
<
< …
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http://skylight.io/safari.html
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app/controllers/hello_controller.rb
> GET /find-hippo HTTP/1.1
> Host: skylight.io
> Accept: text/html,application/xhtml+xml,application/xml;
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app/controllers/hello_controller.rb
class SafariController < ApplicationController
before_action { @hippo = Hippo.first }
def find_hippo
render :hippo
end
end
app/controllers/safari_controller.rb
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http://skylight.io/find-hippo.json
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http://skylight.io/find-hippo.json
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app/controllers/hello_controller.rb
class SafariController < ApplicationController
before_action { @hippo = Hippo.first }
def find_hippo
respond_to do |format|
format.html { render :hippo }
format.json { render json: @hippo }
end
end
end
app/controllers/safari_controller.rb
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http://skylight.io/find-hippo
{
"id": 1,
"name": "Jason",
"created_at": "2020-04-10T17:14:20.771Z",
"updated_at": "2020-04-10T17:14:20.771Z"
}
app/controllers/hello_controller.rb
< HTTP/1.1 200 OK
< Cache-Control: max-age=0, private, must-revalidate
< Date: Thu, 25 Apr 2019 18:52:54 GMT
< Content-Type: application/json
<
< {"id": 1, "name": “Jason", … }
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app/controllers/hello_controller.rb
< HTTP/1.1 200 OK
< Content-Type: text/html
< X-Content-Type-Options: nosniff
< Cache-Control: max-age=0, private, must-revalidate
< Date: Thu, 25 Apr 2019 18:52:54 GMT
<
< …
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TEMPLATE RENDERING
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app/controllers/hello_controller.rb
class SafariController < ApplicationController
before_action { @hippo = Hippo.first }
def find_hippo
render :hippo
end
end
app/controllers/safari_controller.rb
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app/controllers/hello_controller.rb
class SafariController < ApplicationController
before_action { @hippo = Hippo.first }
def find_hippo
render :hippo
end
end
app/controllers/safari_controller.rb
app/controllers/hello_controller.rb
Hey <%= current_user.name %>, meet <%= link_to @hippo.name, @hippo %>!
app/views/safari/hippo.html.erb
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app/controllers/hello_controller.rb
class SafariControllerViewContext < ActionView::Base
include Rails::AllTheHelpers
# link_to, etc.
include MyApp::AllTheHelpers
# current_user, etc.
def initialize(assigns)
assigns.each { |k, v| instance_variable_set("@#{k}", v) }
end
private
# Hey <%= current_user.name %>, meet
# <%= link_to @hippo.name, @hippo %>!
def __compiled_app_templates_hippo_erb
output = ""
output << "Hey "
output << html_escape(current_user.name)
output << ", meet"
output << link_to(html_escape(@hippo.name), @hippo)
output << "!"
output
end
end
NOTE: To see the actual code, look in ActionView!::Rendering, ActionView!::Base,
ActionView!::Renderer, ActionView!::TemplateRenderer, ActionView!::Template
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app/controllers/hello_controller.rb
class SafariControllerViewContext < ActionView::Base
include Rails::AllTheHelpers
# link_to, etc.
include MyApp::AllTheHelpers
# current_user, etc.
def initialize(assigns)
assigns.each { |k, v| instance_variable_set("@#{k}", v) }
end
private
# Hey <%= current_user.name %>, meet
# <%= link_to @hippo.name, @hippo %>!
def __compiled_app_templates_hippo_erb
output = ""
output << "Hey "
output << html_escape(current_user.name)
output << ", meet"
output << link_to(html_escape(@hippo.name), @hippo)
output << "!"
output
end
end
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app/controllers/hello_controller.rb
class SafariControllerViewContext < ActionView::Base
include Rails::AllTheHelpers
# link_to, etc.
include MyApp::AllTheHelpers
# current_user, etc.
def initialize(assigns)
assigns.each { |k, v| instance_variable_set("@#{k}", v) }
end
private
# Hey <%= current_user.name %>, meet
# <%= link_to @hippo.name, @hippo %>!
def __compiled_app_templates_hippo_erb
output = ""
output << "Hey "
output << html_escape(current_user.name)
output << ", meet"
output << link_to(html_escape(@hippo.name), @hippo)
output << "!"
output
end
end
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app/controllers/hello_controller.rb
class SafariControllerViewContext < ActionView::Base
include Rails::AllTheHelpers
# link_to, etc.
include MyApp::AllTheHelpers
# current_user, etc.
def initialize(assigns)
assigns.each { |k, v| instance_variable_set("@#{k}", v) }
end
private
# Hey <%= current_user.name %>, meet
# <%= link_to @hippo.name, @hippo %>!
def __compiled_app_templates_hippo_erb
output = ""
output << "Hey "
output << html_escape(current_user.name)
output << ", meet"
output << link_to(html_escape(@hippo.name), @hippo)
output << "!"
output
end
end
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app/controllers/hello_controller.rb
class SafariControllerViewContext < ActionView::Base
include Rails::AllTheHelpers
# link_to, etc.
include MyApp::AllTheHelpers
# current_user, etc.
def initialize(assigns)
assigns.each { |k, v| instance_variable_set("@#{k}", v) }
end
private
# Hey <%= current_user.name %>, meet
# <%= link_to @hippo.name, @hippo %>!
def __compiled_app_templates_hippo_erb
output = ""
output << "Hey "
output << html_escape(current_user.name)
output << ", meet"
output << link_to(html_escape(@hippo.name), @hippo)
output << "!"
output
end
end
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app/controllers/hello_controller.rb
class SafariControllerViewContext < ActionView::Base
include Rails::AllTheHelpers
# link_to, etc.
include MyApp::AllTheHelpers
# current_user, etc.
def initialize(assigns)
assigns.each { |k, v| instance_variable_set("@#{k}", v) }
end
private
# Hey <%= current_user.name %>, meet
# <%= link_to @hippo.name, @hippo %>!
def __compiled_app_templates_hippo_erb
output = ""
output << "Hey "
output << html_escape(current_user.name)
output << ", meet"
output << link_to(html_escape(@hippo.name), @hippo)
output << "!"
output
end
end
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app/controllers/hello_controller.rb
class SafariControllerViewContext < ActionView::Base
include Rails::AllTheHelpers
# link_to, etc.
include MyApp::AllTheHelpers
# current_user, etc.
def initialize(assigns)
assigns.each { |k, v| instance_variable_set("@#{k}", v) }
end
private
# Hey <%= current_user.name %>, meet
# <%= link_to @hippo.name, @hippo %>!
def __compiled_app_templates_hippo_erb
output = ""
output << "Hey "
output << html_escape(current_user.name)
output << ", meet"
output << link_to(html_escape(@hippo.name), @hippo)
output << "!"
output
end
end
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app/controllers/hello_controller.rb
class SafariControllerViewContext < ActionView::Base
include Rails::AllTheHelpers
# link_to, etc.
include MyApp::AllTheHelpers
# current_user, etc.
def initialize(assigns)
assigns.each { |k, v| instance_variable_set("@#{k}", v) }
end
private
# Hey <%= current_user.name %>, meet
# <%= link_to @hippo.name, @hippo %>!
def __compiled_app_templates_hippo_erb
output = ""
output << "Hey "
output << html_escape(current_user.name)
output << ", meet"
output << link_to(html_escape(@hippo.name), @hippo)
output << "!"
output
end
end
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app/controllers/hello_controller.rb
class SafariControllerViewContext < ActionView::Base
include Rails::AllTheHelpers
# link_to, etc.
include MyApp::AllTheHelpers
# current_user, etc.
def initialize(assigns)
assigns.each { |k, v| instance_variable_set("@#{k}", v) }
end
private
# Hey <%= current_user.name %>, meet
# <%= link_to @hippo.name, @hippo %>!
def __compiled_app_templates_hippo_erb
output = ""
output << "Hey "
output << html_escape(current_user.name)
output << ", meet"
output << link_to(html_escape(@hippo.name), @hippo)
output << "!"
output
end
end
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app/controllers/hello_controller.rb
class SafariControllerViewContext < ActionView::Base
include Rails::AllTheHelpers
# link_to, etc.
include MyApp::AllTheHelpers
# current_user, etc.
def initialize(assigns)
assigns.each { |k, v| instance_variable_set("@#{k}", v) }
end
private
# Hey <%= current_user.name %>, meet
# <%= link_to @hippo.name, @hippo %>!
def __compiled_app_templates_hippo_erb
output = ""
output << "Hey "
output << html_escape(current_user.name)
output << ", meet"
output << link_to(html_escape(@hippo.name), @hippo)
output << "!"
output
end
end
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http://skylight.io/find-hippo
Safari
Hey RailsConf, meet Phyllis!
Hey RailsConf, meet Phyllis!
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http://skylight.io/find-hippo
Safari
Hey RailsConf, meet Phyllis!
Hey RailsConf, meet Phyllis! app/controllers/hello_controller.rb
< HTTP/1.1 200 OK
< Content-Type: text/html
< Content-Length: 306
< Cache-Control: max-age=0, private, must-revalidate
< ETag: W/“60bee75b8031cda7761a332685151766”
< Set-Cookie: _safari_session=some-session-token; path=/;
< X-Content-Type-Options: nosniff
< Date: Thu, 25 Apr 2019 18:52:54 GMT
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No content