Class: RestClient::CacheableResource

Inherits:
Resource
  • Object
show all
Defined in:
lib/cacheability/restclient.rb

Constant Summary collapse

CACHE_DEFAULT_OPTIONS = 
{:verbose => false}

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(*args) ⇒ CacheableResource

Returns a new instance of CacheableResource.



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# File 'lib/cacheability/restclient.rb', line 29

def initialize(*args)
  super(*args)
  # rack-cache creates a singleton, so that there is only one instance of the cache at any time
  @cache = Rack::Cache.new(self, options[:cache] || CACHE_DEFAULT_OPTIONS)
end

Instance Attribute Details

#cache ⇒ Object (readonly)

Returns the value of attribute cache.



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# File 'lib/cacheability/restclient.rb', line 26

def cache
  @cache
end

Instance Method Details

#call(env) ⇒ Object

Follows the SPEC of Rack 1.0: the returned body is always an array of string



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# File 'lib/cacheability/restclient.rb', line 77

def call(env)
  http_headers = env.inject({}) do |out, (header, value)| 
    if header =~ /HTTP_/
      out[header.gsub("HTTP_", '')] = value unless value.nil? || value.empty?
    end
    out
  end
  response = get(debeautify_headers(http_headers), pass_through_cache=false)
  response.headers.delete(:x_content_digest) # don't know why, but it seems to make the validation fail if kept...
  [response.code, debeautify_headers( response.headers ), [response.to_s]]
rescue RestClient::NotModified => e
  # e is a Net::HTTPResponse
  response = RestClient::Response.new("", e.response)
  [304, debeautify_headers( response.headers ), [response.to_s]]
end

#debeautify_headers(headers = {}) ⇒ Object 



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# File 'lib/cacheability/restclient.rb', line 68

def debeautify_headers(headers = {})
  headers.inject({}) do |out, (key, value)|
	out[key.to_s.gsub(/_/, '-')] = value
	out
end
end

#get(additional_headers = {}, pass_through_cache = true) ⇒ Object 



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# File 'lib/cacheability/restclient.rb', line 35

def get(additional_headers = {}, pass_through_cache = true)
  if pass_through_cache && cache
    uri = URI.parse(url)
    uri_path_split = uri.path.split("/")
    path_info = (last_part = uri_path_split.pop) ? "/"+last_part : ""
    script_name = uri_path_split.join("/")
    # minimal rack spec
    env = { 
      "REQUEST_METHOD" => 'GET',
      "SCRIPT_NAME" => script_name,
      "PATH_INFO" => path_info,
      "QUERY_STRING" => uri.query,
      "SERVER_NAME" => uri.host,
      "SERVER_PORT" => uri.port.to_s,
      "rack.version" => Rack::VERSION,
      "rack.run_once" => false,
      "rack.multithread" => true,
      "rack.multiprocess" => true,
      "rack.url_scheme" => uri.scheme,
      "rack.input" => StringIO.new,
      "rack.errors" => logger   # Rack-Cache writes errors into this field
    }
    debeautify_headers(additional_headers).each do |key, value|
      env.merge!("HTTP_"+key.to_s.gsub("-", "_").upcase => value)
    end
    response = MockHTTPResponse.new(cache.call(env))
    env['rack.errors'].close if env['rack.errors'].kind_of?(File)
    RestClient::Response.new(response.body, response)
  else
    super(additional_headers)
  end
end

#logger ⇒ Object

Ugly, but waiting for RestClient to become smarter



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# File 'lib/cacheability/restclient.rb', line 95

def logger
    return StringIO.new unless log_to = RestClient.log
    case log_to
    when 'stdout' then STDOUT
    when 'stderr' then STDERR
    else
      File.new(log_to, 'a')
    end
end