Class: ParallelRender::Middleware

Inherits:
Object
  • Object
show all
Defined in:
lib/parallel_render/middleware.rb

Constant Summary collapse

HTML_TYPE = 
%r{\Atext/html}.freeze

Instance Method Summary collapse

Constructor Details

#initialize(app) ⇒ Middleware

Returns a new instance of Middleware.



16
17
18
 
# File 'lib/parallel_render/middleware.rb', line 16

def initialize(app)
  @app = app
end

Instance Method Details

#call(env) ⇒ Object 



20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
 
# File 'lib/parallel_render/middleware.rb', line 20

def call(env)
  status, headers, body = @app.call(env)

  if html?(headers)
    html = +""
    body.each { |part| html << part }

    (ParallelRender::Current.async_futures || {}).each do |token, future|
      html_fragment = wait_or_empty(future)
      placeholder   = "<!--ASYNC-PLACEHOLDER:#{token}-->"
      html.gsub!(placeholder, html_fragment)
    end

    headers["Content-Length"] = html.bytesize.to_s if headers["Content-Length"]
    ParallelRender::Current.async_futures = {}
    [status, headers, [html]]
  else
    [status, headers, body]
  end
end