feat: Add liquid processing for SMS campaigns (#10981)

Liquid template processing for SMS campaigns
fixes: https://github.com/chatwoot/chatwoot/issues/10980

Co-authored-by: Sojan Jose <sojan@pepalo.com>

app/services/liquid/campaign_template_service.rb

@@ -0,0 +1,26 @@
+class Liquid::CampaignTemplateService
+  pattr_initialize [:campaign!, :contact!]
+
+  def call(message)
+    process_liquid_in_content(message_drops, message)
+  end
+
+  private
+
+  def message_drops
+    {
+      'contact' => ContactDrop.new(contact),
+      'agent' => UserDrop.new(campaign.sender),
+      'inbox' => InboxDrop.new(campaign.inbox),
+      'account' => AccountDrop.new(campaign.account)
+    }
+  end
+
+  def process_liquid_in_content(drops, message)
+    message = message.gsub(/`(.*?)`/m, '{% raw %}`\\1`{% endraw %}')
+    template = Liquid::Template.parse(message)
+    template.render(drops)
+  rescue Liquid::Error
+    message
+  end
+end

app/services/sms/oneoff_sms_campaign_service.rb

@@ -22,7 +22,8 @@ class Sms::OneoffSmsCampaignService
     campaign.account.contacts.tagged_with(audience_labels, any: true).each do |contact|
       next if contact.phone_number.blank?
 
-      send_message(to: contact.phone_number, content: campaign.message)
+      content = Liquid::CampaignTemplateService.new(campaign: campaign, contact: contact).call(campaign.message)
+      send_message(to: contact.phone_number, content: content)
     end
   end
 

app/services/twilio/oneoff_sms_campaign_service.rb

@@ -22,7 +22,8 @@ class Twilio::OneoffSmsCampaignService
     campaign.account.contacts.tagged_with(audience_labels, any: true).each do |contact|
       next if contact.phone_number.blank?
 
-      channel.send_message(to: contact.phone_number, body: campaign.message)
+      content = Liquid::CampaignTemplateService.new(campaign: campaign, contact: contact).call(campaign.message)
+      channel.send_message(to: contact.phone_number, body: content)
     end
   end
 end

spec/services/liquid/campaign_template_service_spec.rb

@@ -0,0 +1,107 @@
+require 'rails_helper'
+
+describe Liquid::CampaignTemplateService do
+  subject(:template_service) { described_class.new(campaign: campaign, contact: contact) }
+
+  let(:account) { create(:account) }
+  let(:agent) { create(:user, account: account) }
+  let(:inbox) { create(:inbox, account: account) }
+  let(:contact) { create(:contact, account: account, name: 'John Doe', phone_number: '+1234567890') }
+  let(:campaign) { create(:campaign, account: account, inbox: inbox, sender: agent, message: message_content) }
+
+  describe '#call' do
+    context 'with liquid template variables' do
+      let(:message_content) { 'Hello {{contact.name}}, this is {{agent.name}} from {{account.name}}' }
+
+      it 'processes liquid template correctly' do
+        result = template_service.call(message_content)
+        agent_drop_name = UserDrop.new(agent).name
+        contact_drop_name = ContactDrop.new(contact).name
+
+        expect(result).to eq("Hello #{contact_drop_name}, this is #{agent_drop_name} from #{account.name}")
+      end
+    end
+
+    context 'with code blocks' do
+      let(:message_content) { 'Check this code: `const x = {{contact.name}}`' }
+
+      it 'preserves code blocks without processing liquid' do
+        result = template_service.call(message_content)
+
+        expect(result).to include('`const x = {{contact.name}}`')
+        expect(result).not_to include(contact.name)
+      end
+    end
+
+    context 'with multiline code blocks' do
+      let(:message_content) do
+        <<~MESSAGE
+          Here's some code:
+          ```
+          function greet() {
+            return "Hello {{contact.name}}";
+          }
+          ```
+        MESSAGE
+      end
+
+      it 'preserves multiline code blocks without processing liquid' do
+        result = template_service.call(message_content)
+
+        expect(result).to include('{{contact.name}}')
+        expect(result).not_to include(contact.name)
+      end
+    end
+
+    context 'with malformed liquid syntax' do
+      let(:message_content) { 'Hello {{contact.name missing closing braces' }
+
+      it 'returns original message when liquid parsing fails' do
+        result = template_service.call(message_content)
+
+        expect(result).to eq(message_content)
+      end
+    end
+
+    context 'with invalid liquid tags' do
+      let(:message_content) { 'Hello {% invalid_tag %} world' }
+
+      it 'returns original message when liquid parsing fails' do
+        result = template_service.call(message_content)
+
+        expect(result).to eq(message_content)
+      end
+    end
+
+    context 'with mixed content' do
+      let(:message_content) { 'Hi {{contact.name}}, use this code: `{{agent.name}}` to contact {{agent.name}}' }
+
+      it 'processes liquid outside code blocks but preserves code blocks' do
+        result = template_service.call(message_content)
+        agent_drop_name = UserDrop.new(agent).name
+        contact_drop_name = ContactDrop.new(contact).name
+
+        expect(result).to include("Hi #{contact_drop_name}")
+        expect(result).to include("contact #{agent_drop_name}")
+        expect(result).to include('`{{agent.name}}`')
+      end
+    end
+
+    context 'with all drop types' do
+      let(:message_content) do
+        'Contact: {{contact.name}}, Agent: {{agent.name}}, Inbox: {{inbox.name}}, Account: {{account.name}}'
+      end
+
+      it 'processes all available drops' do
+        result = template_service.call(message_content)
+        agent_drop_name = UserDrop.new(agent).name
+        contact_drop_name = ContactDrop.new(contact).name
+
+        expect(result).to include("Contact: #{contact_drop_name}")
+        expect(result).to include("Agent: #{agent_drop_name}")
+        expect(result).to include("Inbox: #{inbox.name}")
+        expect(result).to include("Account: #{account.name}")
+      end
+    end
+  end
+end

spec/services/sms/oneoff_sms_campaign_service_spec.rb

@@ -43,5 +43,14 @@ describe Sms::OneoffSmsCampaignService do
       assert_requested(:post, 'https://messaging.bandwidth.com/api/v2/users/1/messages', times: 3)
       expect(campaign.reload.completed?).to be true
     end
+
+    it 'uses liquid template service to process campaign message' do
+      contact = create(:contact, :with_phone_number, account: account)
+      contact.update_labels([label1.title])
+
+      expect(Liquid::CampaignTemplateService).to receive(:new).with(campaign: campaign, contact: contact).and_call_original
+
+      sms_campaign_service.perform
+    end
   end
 end

spec/services/twilio/oneoff_sms_campaign_service_spec.rb

@@ -60,5 +60,15 @@ describe Twilio::OneoffSmsCampaignService do
       sms_campaign_service.perform
       expect(campaign.reload.completed?).to be true
     end
+
+    it 'uses liquid template service to process campaign message' do
+      contact = create(:contact, :with_phone_number, account: account)
+      contact.update_labels([label1.title])
+
+      expect(Liquid::CampaignTemplateService).to receive(:new).with(campaign: campaign, contact: contact).and_call_original
+      expect(twilio_messages).to receive(:create).once
+
+      sms_campaign_service.perform
+    end
   end
 end