Support experimental JWT feature (not available yet) (#356)

* Fix dev dependencies

* Support experimental JWT authentication for the messenger

* Remove user_id from regular user_data payload when using JWT

* Add some script tag helper specs too

* bump version

Author: DamonFstr

intercom-rails.gemspec

@@ -19,6 +19,7 @@ Gem::Specification.new do |s|
   s.test_files = Dir["test/**/*"]
 
   s.add_dependency 'activesupport', '>4.0'
+  s.add_dependency 'jwt', '~> 2.0'
 
   s.add_development_dependency 'rake'
   s.add_development_dependency 'actionpack', '>5.0'

lib/intercom-rails/config.rb

@@ -110,6 +110,7 @@ def self.reset!
     config_accessor :hide_default_launcher
     config_accessor :api_base
     config_accessor :encrypted_mode
+    config_accessor :jwt_enabled
 
     def self.api_key=(*)
       warn "Setting an Intercom API key is no longer supported; remove the `config.api_key = ...` line from config/initializers/intercom.rb"

lib/intercom-rails/script_tag.rb

@@ -2,6 +2,7 @@
 
 require 'active_support/all'
 require 'action_view'
+require 'jwt'
 
 module IntercomRails
 
@@ -17,15 +18,16 @@ class ScriptTag
     include ::ActionView::Helpers::TagHelper
 
     attr_reader :user_details, :company_details, :show_everywhere, :session_duration
-    attr_accessor :secret, :widget_options, :controller, :nonce, :encrypted_mode_enabled, :encrypted_mode
+    attr_accessor :secret, :widget_options, :controller, :nonce, :encrypted_mode_enabled, :encrypted_mode, :jwt_enabled
 
     def initialize(options = {})
       self.secret = options[:secret] || Config.api_secret
       self.widget_options = widget_options_from_config.merge(options[:widget] || {})
       self.controller = options[:controller]
       @show_everywhere = options[:show_everywhere]
       @session_duration = session_duration_from_config
-    
+      self.jwt_enabled = options[:jwt_enabled] || Config.jwt_enabled
+
       initial_user_details = if options[:find_current_user_details]
         find_current_user_details
       else
@@ -119,12 +121,30 @@ def intercom_javascript
       "window.intercomSettings = #{plaintext_javascript};#{intercom_encrypted_payload_javascript}(function(){var w=window;var ic=w.Intercom;if(typeof ic===\"function\"){ic('update',intercomSettings);}else{var d=document;var i=function(){i.c(arguments)};i.q=[];i.c=function(args){i.q.push(args)};w.Intercom=i;function l(){var s=d.createElement('script');s.type='text/javascript';s.async=true;s.src='#{Config.library_url || "https://widget.intercom.io/widget/#{j app_id}"}';var x=d.getElementsByTagName('script')[0];x.parentNode.insertBefore(s,x);}if(document.readyState==='complete'){l();}else if(w.attachEvent){w.attachEvent('onload',l);}else{w.addEventListener('load',l,false);}};})()"
     end
 
+    def generate_jwt
+      return nil unless user_details[:user_id].present?
+      
+      payload = {
+        user_id: user_details[:user_id].to_s,
+        exp: 24.hours.from_now.to_i
+      }
+      JWT.encode(payload, secret, 'HS256')
+    end
+
     def user_details=(user_details)
       @user_details = DateHelper.convert_dates_to_unix_timestamps(user_details || {})
       @user_details = @user_details.with_indifferent_access.tap do |u|
         [:email, :name, :user_id].each { |k| u.delete(k) if u[k].nil? }
 
-        u[:user_hash] ||= user_hash if secret.present? && (u[:user_id] || u[:email]).present?
+        if secret.present?
+          if jwt_enabled && u[:user_id].present?
+            u[:intercom_user_jwt] ||= generate_jwt
+            u.delete(:user_id)  # No need to send plaintext user_id when using JWT
+          elsif (u[:user_id] || u[:email]).present?
+            u[:user_hash] ||= user_hash
+          end
+        end
+        
         u[:app_id] ||= app_id
       end
     end

lib/intercom-rails/version.rb

@@ -1,3 +1,3 @@
 module IntercomRails
-  VERSION = "1.0.2"
+  VERSION = "1.0.3"
 end

spec/config_spec.rb

@@ -114,4 +114,21 @@
       IntercomRails.config.user.company_association = Proc.new { [] }
     end.to output(/no longer supported/).to_stderr
   end
+
+  it 'gets/sets jwt_enabled' do
+    IntercomRails.config.jwt_enabled = true
+    expect(IntercomRails.config.jwt_enabled).to eq(true)
+  end
+
+  it 'defaults jwt_enabled to nil' do
+    IntercomRails.config.reset!
+    expect(IntercomRails.config.jwt_enabled).to eq(nil)
+  end
+
+  it 'allows jwt_enabled in block form' do
+    IntercomRails.config do |config|
+      config.jwt_enabled = true
+    end
+    expect(IntercomRails.config.jwt_enabled).to eq(true)
+  end
 end

spec/script_tag_helper_spec.rb

@@ -49,4 +49,35 @@
       expect(script_tag.to_s).to include('nonce="pJwtLVnwiMaPCxpb41KZguOcC5mGUYD+8RNGcJSlR94="')
     end
   end
+
+  context 'JWT authentication' do
+    before(:each) do
+      allow(Rails).to receive(:env).and_return(ActiveSupport::StringInquirer.new("test"))
+    end
+    before(:each) do
+      IntercomRails.config.api_secret = 'super-secret'
+    end
+
+    it 'enables JWT when configured' do
+      IntercomRails.config.jwt_enabled = true
+      output = intercom_script_tag({
+        user_id: '1234',
+        email: '[email protected]'
+      }).to_s
+    
+      expect(output).to include('intercom_user_jwt')
+      expect(output).not_to include('user_hash')
+    end
+
+    it 'falls back to user_hash when JWT is disabled' do
+      IntercomRails.config.jwt_enabled = false
+      output = intercom_script_tag({
+        user_id: '1234',
+        email: '[email protected]'
+      }).to_s
+      
+      expect(output).not_to include('intercom_user_jwt')
+      expect(output).to include('user_hash')
+    end
+  end
 end

spec/script_tag_spec.rb

@@ -1,5 +1,6 @@
 require 'active_support/time'
 require 'spec_helper'
+require 'jwt'
 
 describe IntercomRails::ScriptTag do
   ScriptTag = IntercomRails::ScriptTag
@@ -301,4 +302,97 @@ def user
     end
   end
 
+  context 'JWT authentication' do
+    before(:each) do
+      IntercomRails.config.app_id = 'jwt_test'
+      IntercomRails.config.api_secret = 'super-secret'
+    end
+
+    it 'does not include JWT when jwt_enabled is false' do
+      script_tag = ScriptTag.new(
+        user_details: { user_id: '1234' },
+        jwt_enabled: false
+      )
+      expect(script_tag.intercom_settings[:intercom_user_jwt]).to be_nil
+    end
+
+    it 'includes JWT when jwt_enabled is true' do
+      script_tag = ScriptTag.new(
+        user_details: { user_id: '1234' },
+        jwt_enabled: true
+      )
+      expect(script_tag.intercom_settings[:intercom_user_jwt]).to be_present
+    end
+
+    it 'does not include user_hash when JWT is enabled' do
+      script_tag = ScriptTag.new(
+        user_details: { user_id: '1234' },
+        jwt_enabled: true
+      )
+      expect(script_tag.intercom_settings[:user_hash]).to be_nil
+    end
+
+    it 'generates a valid JWT with correct payload' do
+      user_id = '1234'
+      script_tag = ScriptTag.new(
+        user_details: { user_id: user_id },
+        jwt_enabled: true
+      )
+      
+      jwt = script_tag.intercom_settings[:intercom_user_jwt]
+      decoded_payload = JWT.decode(jwt, 'super-secret', true, { algorithm: 'HS256' })[0]
+      
+      expect(decoded_payload['user_id']).to eq(user_id)
+      expect(decoded_payload['exp']).to be_within(5).of(24.hours.from_now.to_i)
+    end
+
+    it 'does not generate JWT when user_id is missing' do
+      script_tag = ScriptTag.new(
+        user_details: { email: '[email protected]' },
+        jwt_enabled: true
+      )
+      expect(script_tag.intercom_settings[:intercom_user_jwt]).to be_nil
+    end
+
+    it 'does not generate JWT when api_secret is missing' do
+      IntercomRails.config.api_secret = nil
+      script_tag = ScriptTag.new(
+        user_details: { user_id: '1234' },
+        jwt_enabled: true
+      )
+      expect(script_tag.intercom_settings[:intercom_user_jwt]).to be_nil
+    end
+
+    it 'removes user_id from payload when using JWT' do
+      script_tag = ScriptTag.new(
+        user_details: { 
+          user_id: '1234',
+          email: '[email protected]',
+          name: 'Test User'
+        },
+        jwt_enabled: true
+      )
+      
+      expect(script_tag.intercom_settings[:intercom_user_jwt]).to be_present
+      expect(script_tag.intercom_settings[:user_id]).to be_nil
+      expect(script_tag.intercom_settings[:email]).to eq('[email protected]')
+      expect(script_tag.intercom_settings[:name]).to eq('Test User')
+    end
+
+    it 'keeps user_id in payload when not using JWT' do
+      script_tag = ScriptTag.new(
+        user_details: { 
+          user_id: '1234',
+          email: '[email protected]',
+          name: 'Test User'
+        },
+        jwt_enabled: false
+      )
+      
+      expect(script_tag.intercom_settings[:user_id]).to eq('1234')
+      expect(script_tag.intercom_settings[:email]).to eq('[email protected]')
+      expect(script_tag.intercom_settings[:name]).to eq('Test User')
+    end
+  end
+
 end

spec/spec_helper.rb

@@ -1,6 +1,7 @@
 require 'intercom-rails'
 require 'rspec'
 require 'active_support/core_ext/string/output_safety'
+require 'pry'
 
 def dummy_user(options = {})
   user = Struct.new(:email, :name).new