活動資源抱怨預期的哈希

Question

我使用的活動資源，以從API獲取數據並顯示，
我控制器model.rb有

class Thr::Vol::Dom < ActiveResource::Base 
    class << self 
    def element_path(id, prefix_options = {}, query_options = nil) 
     prefix_options, query_options = split_options(prefix_options) if query_options.nil? 
     "#{prefix(prefix_options)}#{collection_name}/#{id}#{query_string(query_options)}" 
    end 

    def collection_path(prefix_options = {}, query_options = nil) 
     prefix_options, query_options = split_options(prefix_options) if query_options.nil? 
     "#{prefix(prefix_options)}#{collection_name}#{query_string(query_options)}" 
    end 
    end 

    ActiveResource::Base.site = 'http://10.00.0.00:8888/' 

    self.format = :json 
    self.collection_name= "/vv/test/domains" 

    def self.find 
    x = superclass.find(:one, :from => '/vv/test/domains/2013-06-25T05:03Z') 
    x 
    end 
end 

當我把這個蘇氨酸::卷:: Dom.find方法返回以下錯誤：

ArgumentError: expected an attributes Hash, 
    got ["0.0.0.0", "1.1.1.1", "2.2.2.2", "3.3.3.3", "4.4.4.4"] 

API被預期將這樣的事情

{"abs.com":["0.0.0.0", "1.1.1.1", "2.2.2.2", "3.3.3.3", "4.4.4.4"]} 

我打了電話。

該API返回正確的散列，但我猜測活動資源無法正確讀取它，它直接讀取散列鍵值對中的值。

我想修復這個「ArgumentError」錯誤，我想顯示在視圖中返回的哈希的內容。

Answer 1

API正在返回一個JSON對象，而不是Ruby哈希。你需要使用Ruby的JSON模塊，將其轉換成一個哈希：

require 'JSON' 

hash = JSON.parse('{"abs.com":["0.0.0.0", "1.1.1.1", "2.2.2.2", "3.3.3.3", "4.4.4.4"]}') 

這將返回一個哈希值，然後你會發現，如預期的鍵/值對將工作：

hash["abs.com"] => ["0.0.0.0", "1.1.1.1", "2.2.2.2", "3.3.3.3", "4.4.4.4"] 

Answer 2

，您可以更改的ActiveResource處理與

class YourModel < ActiveResource::Base 
    self.format = ::JsonFormatter.new(:collection_name) 
end 

JSON響應在lib/json_formatter.rb

class JsonFormatter 
    include ActiveResource::Formats::JsonFormat 

    attr_reader :collection_name 

    def initialize(collection_name) 
    @collection_name = collection_name.to_s 
    end 

    def decode(json) 
    remove_root(ActiveSupport::JSON.decode(json)) 
    end 

    private 

    def remove_root(data) 
    if data.is_a?(Hash) && data[collection_name] 
     data[collection_name] 
    else 
     data 
    end 
    end 
end 

如果您通過self.format = ::JsonFormatter.new(:categories)，它會在您的API返回的json中找到並刪除categories根元素。