FEATURE: Add DallE support to AI helper's illustrate post (#404)

config/locales/server.en.yml

@@ -59,6 +59,7 @@ en:
     ai_helper_custom_prompts_allowed_groups: "Users on these groups will see the custom prompt option in the AI helper."
     ai_helper_automatic_chat_thread_title_delay: "Delay in minutes before the AI helper automatically sets the chat thread title."
     ai_helper_automatic_chat_thread_title: "Automatically set the chat thread titles based on thread contents."
+    ai_helper_illustrate_post_model: "Model to use for the composer AI helper's illustrate post feature"
 
     ai_embeddings_enabled: "Enable the embeddings module."
     ai_embeddings_discourse_service_api_endpoint: "URL where the API is running for the embeddings module"
@@ -129,7 +130,9 @@ en:
         explain: "Explain"
         illustrate_post: "Illustrate Post"
       painter:
-        attribution: "Image by Stable Diffusion XL"
+        attribution: 
+          stable_diffusion_xl: "Image by Stable Diffusion XL"
+          dall_e_3: "Image by DALL-E 3"
 
     ai_bot:
       placeholder_reply: "I will reply shortly..."

config/settings.yml

@@ -199,6 +199,13 @@ discourse_ai:
     default: false
   ai_helper_automatic_chat_thread_title_delay:
     default: 5
+  ai_helper_illustrate_post_model:
+    default: disabled
+    type: enum
+    choices:
+      - stable_diffusion_xl
+      - dall_e_3
+      - disabled
 
   ai_embeddings_enabled:
     default: false

lib/ai_helper/assistant.rb

@@ -11,9 +11,11 @@ module DiscourseAi
           prompts = [cp.enabled_by_name(name_filter)]
         else
           prompts = cp.where(enabled: true)
-          # Only show the illustrate_post prompt if the API key is present
+          # Hide illustrate_post if disabled
           prompts =
-            prompts.where.not(name: "illustrate_post") if !SiteSetting.ai_stability_api_key.present?
+            prompts.where.not(
+              name: "illustrate_post",
+            ) if SiteSetting.ai_helper_illustrate_post_model == "disabled"
         end
 
         prompts.map do |prompt|

lib/ai_helper/painter.rb

@@ -3,35 +3,59 @@
 module DiscourseAi
   module AiHelper
     class Painter
-      def commission_thumbnails(theme, user)
-        stable_diffusion_prompt = difussion_prompt(theme, user)
+      def commission_thumbnails(input, user)
+        return [] if input.blank?
 
+        model = SiteSetting.ai_helper_illustrate_post_model
+        attribution = "discourse_ai.ai_helper.painter.attribution.#{model}"
+
+        if model == "stable_diffusion_xl"
+          stable_diffusion_prompt = difussion_prompt(input, user)
           return [] if stable_diffusion_prompt.blank?
 
-        base64_artifacts =
+          artifacts =
             DiscourseAi::Inference::StabilityGenerator
               .perform!(stable_diffusion_prompt)
               .dig(:artifacts)
               .to_a
               .map { |art| art[:base64] }
 
-        base64_artifacts.each_with_index.map do |artifact, i|
+          base64_to_image(artifacts, user.id)
+        elsif model == "dall_e_3"
+          api_key = SiteSetting.ai_openai_api_key
+          api_url = SiteSetting.ai_openai_dall_e_3_url
+
+          artifacts =
+            DiscourseAi::Inference::OpenAiImageGenerator
+              .perform!(input, api_key: api_key, api_url: api_url)
+              .dig(:data)
+              .to_a
+              .map { |art| art[:b64_json] }
+
+          base64_to_image(artifacts, user.id)
+        end
+      end
+
+      private
+
+      def base64_to_image(artifacts, user_id)
+        attribution =
+          I18n.t(
+            "discourse_ai.ai_helper.painter.attribution.#{SiteSetting.ai_helper_illustrate_post_model}",
+          )
+
+        artifacts.each_with_index.map do |art, i|
           f = Tempfile.new("v1_txt2img_#{i}.png")
           f.binmode
-          f.write(Base64.decode64(artifact))
+          f.write(Base64.decode64(art))
           f.rewind
-          upload =
-            UploadCreator.new(f, I18n.t("discourse_ai.ai_helper.painter.attribution")).create_for(
-              user.id,
-            )
+          upload = UploadCreator.new(f, attribution).create_for(user_id)
           f.unlink
 
           UploadSerializer.new(upload, root: false)
         end
       end
 
-      private
-
       def difussion_prompt(text, user)
         prompt = { insts: <<~TEXT, input: text }
           Provide me a StableDiffusion prompt to generate an image that illustrates the following post in 40 words or less, be creative.

spec/lib/modules/ai_helper/assistant_spec.rb

@@ -36,8 +36,8 @@ RSpec.describe DiscourseAi::AiHelper::Assistant do
       end
     end
 
-    context "when stability API key is present" do
-      before { SiteSetting.ai_stability_api_key = "foo" }
+    context "when illustrate post model is enabled" do
+      before { SiteSetting.ai_helper_illustrate_post_model = "stable_diffusion_xl" }
 
       it "returns the illustrate_post prompt in the list of all prompts" do
         prompts = subject.available_prompts

spec/lib/modules/ai_helper/painter_spec.rb

@@ -8,9 +8,14 @@ RSpec.describe DiscourseAi::AiHelper::Painter do
   before do
     SiteSetting.ai_stability_api_url = "https://api.stability.dev"
     SiteSetting.ai_stability_api_key = "abc"
+    SiteSetting.ai_openai_api_key = "abc"
+    SiteSetting.ai_openai_dall_e_3_url = "https://api.openai.com/v1/images/generations"
   end
 
   describe "#commission_thumbnails" do
+    context "when illustrate post model is stable_diffusion_xl" do
+      before { SiteSetting.ai_helper_illustrate_post_model = "stable_diffusion_xl" }
+
       let(:artifacts) do
         %w[
           iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAADUlEQVR42mP8z8BQDwAEhQGAhKmMIQAAAABJRU5ErkJggg==
@@ -40,9 +45,44 @@ RSpec.describe DiscourseAi::AiHelper::Painter do
 
         thumbnail_urls = Upload.last(4).map(&:short_url)
 
-      expect(thumbnails.map { |upload_serializer| upload_serializer.short_url }).to contain_exactly(
-        *thumbnail_urls,
-      )
+        expect(
+          thumbnails.map { |upload_serializer| upload_serializer.short_url },
+        ).to contain_exactly(*thumbnail_urls)
+      end
+    end
+
+    context "when illustrate post model is dall_e_3" do
+      before { SiteSetting.ai_helper_illustrate_post_model = "dall_e_3" }
+
+      let(:artifacts) do
+        %w[
+          iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAADUlEQVR42mP8z8BQDwAEhQGAhKmMIQAAAABJRU5ErkJggg==
+        ]
+      end
+
+      let(:raw_content) do
+        "Poetry is a form of artistic expression that uses language aesthetically and rhythmically to evoke emotions and ideas."
+      end
+
+      it "returns an image sample" do
+        post = Fabricate(:post)
+
+        data = [{ b64_json: artifacts.first, revised_prompt: "colors on a canvas" }]
+        WebMock
+          .stub_request(:post, "https://api.openai.com/v1/images/generations")
+          .with do |request|
+            json = JSON.parse(request.body, symbolize_names: true)
+            true
+          end
+          .to_return(status: 200, body: { data: data }.to_json)
+
+        thumbnails = subject.commission_thumbnails(raw_content, user)
+        thumbnail_urls = Upload.last(1).map(&:short_url)
+
+        expect(
+          thumbnails.map { |upload_serializer| upload_serializer.short_url },
+        ).to contain_exactly(*thumbnail_urls)
+      end
     end
   end
 end

spec/requests/ai_helper/assistant_controller_spec.rb

@@ -138,7 +138,7 @@ RSpec.describe DiscourseAi::AiHelper::AssistantController do
         sign_in(user)
         user.group_ids = [Group::AUTO_GROUPS[:trust_level_1]]
         SiteSetting.ai_helper_allowed_groups = Group::AUTO_GROUPS[:trust_level_1]
-        SiteSetting.ai_stability_api_key = "foo"
+        SiteSetting.ai_helper_illustrate_post_model = "stable_diffusion_xl"
       end
 
       it "returns a list of prompts when no name_filter is provided" do