session method cannot be called 2 times in controller - ruby-on-rails

Question

In the code below, when the #call method executes, it redirects the call to the #connect method to play an audio, then the #connect method redirects to #menu_selection where everything breaks. the error I get in heroku logs is that sessions is nil or defined.
What I dont understand is that I am already using session[:user_id] in the first method #call. why is it no defined in the #menu_selection method?
def call
#list = User.find_by(id: session[:user_id]).contact_lists.find_by(id: session[:last_contact_list_id])
#contacts = #list.contacts
#client = Twilio::REST::Client.new(##account_sid, ##auth_token)
#contacts.each do |contact|
#call = #client.account.calls.create(
:from => '[phone]', # From your Twilio number
:to => '+1' + contact.phone , # To any number
:url => root_url + "connect"
)
end
redirect_to root_path
end
def connect
response = Twilio::TwiML::Response.new do |r|
r.Play 'https://clyp.it/l1qz52x5.mp3'
r.Gather numDigits: '1', action: menu_path do |g|
g.Play 'https://a.clyp.it/2mue3ocn.mp3'
end
end
render :xml => response.to_xml
end
def menu_selection
list = User.find_by(id: session[:user_id]).contact_lists.find_by(id: session[:last_contact_list_id])
user_selection = params[:Digits]
#client = Twilio::REST::Client.new(##account_sid, ##auth_token)
case user_selection
when "1"
#output = "say something."
twiml_say(#output, true)
when "2"
twiml_dial("+1805XXXXX")
when "3"
#output = "Bye Bye..."
twiml_say(#output, true)
end
end
In the #menu_selection method I get the error : undefined local variable or method `session'
Its in the first line where I'm defining the "list" variable.
I never had this kind of issue before. If anyone knows whats going on, I would appreciate your help.
I tried defining the first #list variable as a class variable outside of the method #call but It gives me the same error that I get now. I also tried making it a class variable inside the #call method to try using it in #menu_selection method, but I get an "##list is undefined" error.

Answer 1

Twilio developer evangelist here.
The problem here is that the session in the #call action is between your user and the server. However, when you initiate a call and Twilio calls back to your server the session between Twilio and the server is completely different.
In this situation, you need to pass the data you need Twilio to know through your URL. So, instead of just sending the connect URL, send it with the parameters you need later. So your #call action would look like:
def call
#list = User.find_by(id: session[:user_id]).contact_lists.find_by(id: session[:last_contact_list_id])
#contacts = #list.contacts
#client = Twilio::REST::Client.new(##account_sid, ##auth_token)
#contacts.each do |contact|
#call = #client.account.calls.create(
:from => '[phone]', # From your Twilio number
:to => '+1' + contact.phone , # To any number
:url => root_url + "connect?user_id=#{session[:user_id]}&last_contact_list_id=#{session[:last_contact_list_id]}"
)
end
redirect_to root_path
end
Then, your #connect action will need to pass those on to your #menu_selection action too (note the menu_path line):
def connect
response = Twilio::TwiML::Response.new do |r|
r.Play 'https://clyp.it/l1qz52x5.mp3'
r.Gather numDigits: '1', action: menu_path(:user_id => params[:user_id], :last_contact_list_id => params[:last_contact_list_id] do |g|
g.Play 'https://a.clyp.it/2mue3ocn.mp3'
end
end
render :xml => response.to_xml
end
Finally, you will be able to use those parameters, instead of the session, in your #menu_selection action:
def menu_selection
list = User.find_by(id: params[:user_id]).contact_lists.find_by(id: params[:last_contact_list_id])
user_selection = params[:Digits]
#client = Twilio::REST::Client.new(##account_sid, ##auth_token)
case user_selection
when "1"
#output = "say something."
twiml_say(#output, true)
when "2"
twiml_dial("+1805XXXXX")
when "3"
#output = "Bye Bye..."
twiml_say(#output, true)
end
end
Let me know if this helps!