Class: FaradayStack::RackCompatible

Inherits:
Object
  • Object
show all
Defined in:
lib/faraday_stack/rack_compatible.rb

Overview

Wraps a handler originally written for Rack to make it compatible with Faraday.

Experimental. Only handles changes in request headers.

Constant Summary collapse

NonPrefixedHeaders =
%w[CONTENT_LENGTH CONTENT_TYPE]

Instance Method Summary collapse

Constructor Details

#initialize(app, rack_handler, *args) ⇒ RackCompatible

Returns a new instance of RackCompatible.


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# File 'lib/faraday_stack/rack_compatible.rb', line 8

def initialize(app, rack_handler, *args)
  # tiny middleware that decomposes a Faraday::Response to standard Rack
  # array: [status, headers, body]
  compatible_app = lambda do |env|
    restore_env(env)
    response = app.call(env)
    [response.status, response.headers, Array(response.body)]
  end
  @rack = rack_handler.new(compatible_app, *args)
end

Instance Method Details

#call(env) ⇒ Object


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# File 'lib/faraday_stack/rack_compatible.rb', line 19

def call(env)
  prepare_env(env)
  rack_response = @rack.call(env)
  finalize_response(env, rack_response)
end

#finalize_response(env, rack_response) ⇒ Object


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# File 'lib/faraday_stack/rack_compatible.rb', line 64

def finalize_response(env, rack_response)
  status, headers, body = rack_response
  body = body.inject('') { |str, part| str << part }
  headers = Faraday::Utils::Headers.new(headers) unless Faraday::Utils::Headers === headers
  
  response_env = { :status => status, :body => body, :response_headers => headers }
  
  env[:response] ||= Faraday::Response.new({})
  env[:response].env.update(response_env)
  env[:response]
end

#prepare_env(env) ⇒ Object

faraday to rack-compatible


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# File 'lib/faraday_stack/rack_compatible.rb', line 28

def prepare_env(env)
  env[:request_headers].each do |name, value|
    name = name.upcase.tr('-', '_')
    name = "HTTP_#{name}" unless NonPrefixedHeaders.include? name
    env[name] = value
  end
  
  url = env[:url]
  env['rack.url_scheme'] = url.scheme
  env['PATH_INFO'] = url.path
  env['SERVER_PORT'] = url.inferred_port
  env['QUERY_STRING'] = url.query
  env['REQUEST_METHOD'] = env[:method].to_s.upcase
  
  env['rack.errors'] ||= StringIO.new
  
  env
end

#restore_env(env) ⇒ Object

rack to faraday-compatible


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# File 'lib/faraday_stack/rack_compatible.rb', line 48

def restore_env(env)
  headers = env[:request_headers]
  headers.clear
  
  env.each do |name, value|
    next unless String === name
    if NonPrefixedHeaders.include? name or name.index('HTTP_') == 0
      name = name.sub(/^HTTP_/, '').downcase.tr('_', '-')
      headers[name] = value
    end
  end
  
  env[:method] = env['REQUEST_METHOD'].downcase.to_sym
  env
end