Plugin Module Help

rubyonrails-talk
#1

Nate Leavitt wrote:

First off, I'm an intermediate Rails developer who is still learning the
inner workings of Rails.. so here is my situation/problem:

I have written a Plugin that accesses a third party API. Within the
Plugin I had multiple classes that inherit from one another. Example:

**************************
Old Code (Plugin Classes)
**************************

class ApiConn
attr_accessor :api_url, :api_key

def initialize(url, key)
   @api_url = url
   @api_key = key
end

def api_perform(class_type, method, *args)
   begin
     server = XMLRPC::Client.new3({'host' => self.api_url, 'path' =>
"/api/xmlrpc", 'port' => 443, 'use_ssl' => true})
     result = server.call("#{class_type}.#{method}", self.api_key,
*args)
   rescue XMLRPC::FaultException => e
     puts "*** Api Error: #{e.faultCode} - #{e.faultString} ***"
   end

   return result
end
end

class ContactService < ApiConn
  def api_contact_add(data)
    api_perform('ContactService', 'add', data)
  end
end

....

**************************
Then within my ApplicationController I have this:
**************************

Account
def current_account
  @current_account ||=
Rails.cache.fetch("ch:current:account:#{current_subdomain}"){
    Account.find_by_subdomain(current_subdomain)
  }
end

def app_contact_svc
  @app_contact_svc ||=
ContactService.new("#{current_account.api_url}.application.com",
current_account.api_key)
end

**************************

Well, this has worked fine. However, as I've been going through my
controllers, I've noticed that a lot of these calls should be moved to
the models. For example, I have an ActiveRecord model named Contact and
I would like to be able to call api_contact_add from within the instance
of that model. I know I would be able to do that by switching the
plugin to a module.

However, here is the problem: The rails app uses accounts and each
account has a different api_url and api_key. The current_account(see
above) is set by the subdomain being used.

So I guess my question is how I can have module attributes set
specifically for each account through multiple models?

So instead of doing Contact.new(api_url, key) in an initialize statement
for each class that includes the ApiConn module, I would like these
values set once for all models specific to the account.

I hope this make sense :slight_smile:

Perhaps something like:

module ContactService
   def self.set_account(url, key)
     Thread.current[:api_conn] = ApiConn.new(url, key)
   end

   def api_contact_add(data)
     Thread.current[:api_conn].api_perform('ContactService', 'add', data)
   end
end

before_filter do
   ContactService.set_account(
   "#{current_account.api_url}.application.com", current_account.api_key)
end

#2

Nate Leavitt wrote:

Is that multi-thread safe for the newer versions of rails?

Yes.

#3

Nate Leavitt wrote:

Is the thread specific for the request in rails? Meaning.. the before_filter will be run on each rails action/request therefore is a new thread created in rails for that process? Jeez.. I hope I'm explaining it properly :slight_smile:

Yes, each thread only carries one request at time.

Also, since that before filter is creating a new AppConn obj do I have to worry about performance? It just seems that creating a new AppConn for each rails request seems like overkill. Am I wrong in thinking that?

Creating such a small AppConn object with each request shouldn't
be a problem.

If it is you can instead do

    def self.set_account(url, key)
      if ac = Thread.current[:api_conn]
        ac.url, ac.key = url, key
      else
        Thread.current[:api_conn] = ApiConn.new(url, key)
      end
    end

#4

Thanks Mark!