Question

我有一个Rails 3应用程序，我使用以下代码来解析JSON帖子：

email_payload = JSON.parse(params[:payload])
Result.create(:from => email_payload['from'], :from_name => email_payload['from_name'], :from_address => email_payload['from_address'], :date => email_payload['date'], :html_body => email_payload['html_body'], :priority => email_payload['priority'], :spam_status => email_payload['spam_status'], :subject => email_payload['subject'])

JSON帖子数据如下：

payload{ "address_identifier": null, "attachments": [ [ "twitter.png", "image/png", 3029, "http://api.deliverhq.com/api/incoming/attachment/7gdd71wo75/5772412/0" ] ], "cc": null, "date": "Thu, 25 Oct 2012 22:04:20 +0100"

我正在尝试解析如何解析URL，在本例中为http://api.deliverhq.com/api/incoming/attachment/7gdd71wo75/5772412/0，然后将URL输入数据库。

:url => email_payload['attachments']

不起作用，因为附件中有多个值，并且：

email_attachments_payload = JSON.parse(params[:payload][:attachments])
:url => email_attachments_payload['URL']

将无效，因为该URL没有标识符。对于这个特定的应用程序，应该只有一个附件，因此如果可能的话，选择.first可能是一个选项。

任何指针都将不胜感激！

更新

添加：

email_payload[:attachments][0][4]

导致以下异常错误：

NoMethodError: undefined method []' for nil:NilClass

更新2

def receive_fax
    if request.get?
        render :text => "hello"
    elsif request.post?   
      email_payload = JSON.parse(params[:payload])     
      Fax.create(:from => email_payload['from'], :from_name => email_payload['from_name'], :from_address => email_payload['from_address'], :date => email_payload['date'], :html_body => email_payload['html_body'], :priority => email_payload['priority'], :spam_status => email_payload['spam_status'], :subject => email_payload['subject'], :fax => email_payload[:attachments][0][3])
      render :text => "success"
    else
      render :text => "error"
    end
  end

Answer 1

在irb：

require 'json'

email_payload = JSON.parse('{ "address_identifier": null, "attachments": [ [ "twitter.png", "image/png", 3029, "http://api.deliverhq.com/api/incoming/attachment/7gdd71wo75/5772412/0" ] ], "cc": null, "date": "Thu, 25 Oct 2012 22:04:20 +0100" }')
#=> {"address_identifier"=>nil, "attachments"=>[["twitter.png", "image/png", 3029, "http://api.deliverhq.com/api/incoming/attachment/7gdd71wo75/5772412/0"]], "cc"=>nil, "date"=>"Thu, 25 Oct 2012 22:04:20 +0100"}
email_payload['attachments'][0][3]
#=> "http://api.deliverhq.com/api/incoming/attachment/7gdd71wo75/5772412/0"

如果这不起作用，那么还有其他一些你没有在上面描述的内容。

更新：在JSON.parse返回的哈希中，attachments键应为字符串（'attachments'），而不是符号（:attachments）。更新了上面的答案。

Answer 2

请尝试：email_payload ['attachments'] [0] [3]

看来问题可能是：附件（符号）和'附件'（字符串）之间的区别。

解析嵌入的字符串形式JSON

2 个答案: