Active Model XML serialization: undefined method `[] 'for nil: NilClass

Originally from here , I am posting a new thread to focus on my problem resolving the "to_xml" method.

What I am trying to do: do a conversion from Ruby Object (Whois :: Record) to XML.

I am currently using ActiveModel but not ActiveRecord (like previous thread for reasons)

Here is the relevant controller:

def lookup
   domain = params[:domain]
   @whois = Request.new
   @whois.search(domain)

   respond_to do |format|
     if @whois != nil
       format.html
       format.json {render :json => @whois.body}
       format.xml {render :xml => @whois}
     else
       format.html { render :new }
       format.json { render json: @request.errors, status: :unprocessable_entity }
     end
   end
end

      

        
        
        
      

    

Note that @whois is NOT a Whois :: Record object, but the class that contains such an object (in the body property )

And the view:

<% if @whois != nil %>

    <%= @whois %>
    <!--JSON-->
    <%= @whois.body.to_json %>
    <!--XML-->
    <% byebug %>
    <%= @whois.to_xml %>

<% end %>

      

        
        
        
      

    

Note that the to_json method works fine, so the fact that ruby ​​is throwing a nilClass exception is rather strange.

Here is the stacktrace starting from before_xml :

/home/nico/.rvmruby(2.1.3) gems / activesupport-4.1.6 / lib / active_support / xml_mini.rb: 148: in _dasherize' /home/nico/.rvmruby (2.1.3) gems/activesupport-4.1.6/lib/active_support/xml_mini.rb:140:in

rename_key '/home/nico/.rvmruby(2.1.3) gems / activesupport-4.1 .6 / lib / active_support / xml_mini.rb: 119: into to_tag' /home/nico/.rvmruby (2.1.3) gems/activesupport-4.1.6/lib/active_support/core_ext/hash/conversions.rb:88:in

block (2 levels) in to_xml '/home/nico/.rvmruby(2.1.3) gems / activesupport-4.1.6 / lib / active_support / core_ext / hash / convertions.rb: 88: in each' /home/nico/.rvmruby (2.1.3) gems/activesupport-4.1.6/lib/active_support/core_ext/hash/conversions.rb:88:in

block in to_xml '/home/nico/.rvmruby(2.1.3) gems / builder-3.2.2 / lib / builder / xmlbase.rb: 175: in call' /home/nico/.rvmruby (2.1.3) gems/builder-3.2.2/lib/builder/xmlbase.rb:175:in

_nested_structures' / home / nico /. rvmruby (2.1.3) gems / builder-3.2.2 / lib / builder / xmlbase.rb: 68: in tag!' /home/nico/.rvmruby (2.1.3) gems/activesupport-4.1.6/lib/active_support/core_ext/hash/conversions.rb:87:in

to_xml 'app / models / request.rb: 26: in `to_xml'

Byebug gives me an advantage as such:

to_xml > ActiveSupport :: SafeBuffer :: OutpuBuffer # safe_concat

   153:     def safe_concat(value)
=> 154:       raise SafeConcatError unless html_safe?
   155:       original_concat(value)
   156:     end

      

        
        
        
      

    

Note: html_safe? here is set to "true" and value is "\ t"

original_concat

File activesupport / lib / active_support / core_ext / string / output_safety.rb, line 132   Alias ​​for original_concat

def concat(value)
  if !html_safe? || value.html_safe?
    super(value)
  else
    super(ERB::Util.h(value))
  end
end

      

        
        
        
      

    

And when I step over, I return to the to_xml method, which throws a fit for not having a class to call the method. I would appreciate any help, thanks.

Edit

Here is a request for a class from my model:

#This is a generic class for checking Key authenticity and sending requests to the engine
#Furthermore, this class will contain the WHOIS response in body

include ActiveModel::Model
include ActiveModel::Serializers::JSON
include ActiveModel::Serializers::Xml

attr_accessor :body

def attributes
    {body => nil}
end


def to_xml(options = {})
    to_xml_opts = {:skip_types => true} # no type information, not such a great idea!
    to_xml_opts.merge!(options.slice(:builder, :skip_instruct))
    # a builder instance is provided when to_xml is called on a collection of instructors,
    # in which case you would not want to have <?xml ...?> added to each item
    to_xml_opts[:root] ||= "instructor"
    self.attributes.to_xml(to_xml_opts)
end

def search(domain)
    # since rails compiles the code before executing a search once,
    # we have to catch niClass exceptions and such
    if domain != ( nil && true && "" )
        c = Whois::Client.new
        self.body = c.lookup(domain)
    end
end

      

        
        
        
      

    

I used this as from what I understood that XML is trying to define a type for each attribute and has problems with named objects. Here's a stream of about_xml and objects in rails