Assistant generator creates a basic UI (#112)

* WIP: Adding rough views+controller to be used by the assistant generator

* wip

* wip

* wip

* fix linter

* bump webrick

* enhancements

* enhancements

* Add post_install_message

* Views use turbo so we need to add turbo-rails to the host Gemfile

* wip

* Fixes

* Fix this

* Fix linter

* Bump langchainrb version

* Bug fix since the namespace had changed in langchainrb

* Fix spec

* Update Gemfile.lock

* Assistant generator UI (#125)

* remove os files and ignore globally

* ignore ruby-version

* add destroy instructions

* test that the views get generated

* readme update

---------

Co-authored-by: Sergio Bayona <[email protected]>

Author: andreibondarev

.gitignore

@@ -6,6 +6,8 @@
 /pkg/
 /spec/reports/
 /tmp/
+.ruby-version
 
 # rspec failure tracking
 .rspec_status
+**/.DS_Store

README.md

@@ -147,7 +147,18 @@ prompt.render(adjective: "funny", subject: "elephants")
 # => "Tell me a funny joke about elephants."
 ```
 
-### Assistant Generator - adds assistant capabilities to your ActiveRecord model
+### Assistant Generator - adds Langchain::Assistant capabilities to your Rails app
+
+This generator adds Langchain::Assistant-related ActiveRecord models, migrations, controllers, views and route to your Rails app. You can start creating assistants and chatting with them in immediately.
+
+```bash
+rails generate langchainrb_rails:assistant --llm=openai
+```
+
+Available `--llm` options: `anthropic`, `cohere`, `google_palm`, `google_gemini`, `google_vertex_ai`, `hugging_face`, `llama_cpp`, `mistral_ai`, `ollama`, `openai`, and `replicate`. The selected LLM will be used to generate completions.
+
+To remove the generated files, run:
+
 ```bash
-rails generate langchainrb_rails:assistant
-```
+rails destroy langchainrb_rails:assistant
+```

lib/langchainrb_overrides/assistant.rb

@@ -58,7 +58,8 @@ def load(id)
           llm: ar_assistant.llm,
           tools: tools,
           instructions: ar_assistant.instructions,
-          tool_choice: ar_assistant.tool_choice
+          # Default to auto to match the behavior of the original Langchain::Assistant
+          tool_choice: ar_assistant.tool_choice || "auto"
         )
 
         ar_assistant.messages.each do |ar_message|

lib/langchainrb_rails/generators/langchainrb_rails/assistant_generator.rb

@@ -51,12 +51,60 @@ def migration_version
         "[#{::ActiveRecord::VERSION::MAJOR}.#{::ActiveRecord::VERSION::MINOR}]"
       end
 
+      def create_controller_file
+        template "assistant/controllers/assistants_controller.rb", "app/controllers/assistants_controller.rb"
+      end
+
+      def create_view_files
+        template "assistant/views/_message.html.erb", "app/views/assistants/_message.html.erb"
+        template "assistant/views/_message_form.html.erb", "app/views/assistants/_message_form.html.erb"
+        template "assistant/views/chat.turbo_stream.erb", "app/views/assistants/chat.turbo_stream.erb"
+        template "assistant/views/edit.html.erb", "app/views/assistants/edit.html.erb"
+        template "assistant/views/index.html.erb", "app/views/assistants/index.html.erb"
+        template "assistant/views/new.html.erb", "app/views/assistants/new.html.erb"
+        template "assistant/views/show.html.erb", "app/views/assistants/show.html.erb"
+      end
+
+      def add_routes
+        route <<~EOS
+          resources :assistants do
+            member do
+              post 'chat'
+            end
+          end
+        EOS
+      end
+
+      # TODO: Copy stylesheet into app/assets/stylesheets or whatever the host app uses
+      def copy_stylesheets
+        template "assistant/stylesheets/chat.css", "app/assets/stylesheets/chat.css"
+      end
+
       # TODO: Depending on the LLM provider, we may need to add additional gems
-      # def add_to_gemfile
-      # end
+      def add_to_gemfile
+        gem_name = "turbo-rails"
+
+        if gem_exists?(gem_name)
+          say_status :skipped, "#{gem_name} already exists in Gemfile"
+        else
+          inside Rails.root do
+            run "bundle add #{gem_name}"
+          end
+        end
+      end
+
+      def post_install_message
+        say "1. Set an environment variable ENV['#{llm.upcase}_API_KEY'] for your #{llm_class}."
+        say "2. Run `rails db:migrate` to apply the database migrations to create the assistants and messages tables."
+        say "3. Start your Rails server and navigate to `/assistants` to create your first assistant!"
+      end
 
       private
 
+      def gem_exists?(gem_name)
+        File.read(Rails.root.join("Gemfile")).include?(gem_name)
+      end
+
       # @return [String] LLM provider to use
       def llm
         options["llm"]

lib/langchainrb_rails/generators/langchainrb_rails/templates/assistant/controllers/assistants_controller.rb

@@ -0,0 +1,70 @@
+# frozen_string_literal: true
+
+class AssistantsController < ApplicationController
+  before_action :set_assistant, only: [:show, :edit, :update, :chat, :destroy]
+
+  def index
+    @assistants = Assistant.all
+  end
+
+  def new
+    @assistant = Assistant.new
+  end
+
+  def create
+    @assistant = Assistant.new(assistant_params)
+    if @assistant.save
+      redirect_to @assistant, notice: "Assistant was successfully created."
+    else
+      render :new
+    end
+  end
+
+  def show
+    @assistants = Assistant.all
+    @assistant = Assistant.find(params[:id])
+    @messages = @assistant.messages
+    @message = Message.new
+  end
+
+  def edit
+  end
+
+  def update
+    if @assistant.update(assistant_params)
+      redirect_to @assistant, notice: "Assistant was successfully updated."
+    else
+      render :edit
+    end
+  end
+
+  def chat
+    @assistant = Assistant.find(params[:id])
+    @message = @assistant.messages.create(role: "user", content: params[:message][:content])
+
+    langchain_assistant = Langchain::Assistant.load(@assistant.id)
+    messages = langchain_assistant.add_message_and_run!(content: params[:message][:content])
+    response = messages.last
+
+    @response = @assistant.messages.create(role: "assistant", content: response.content)
+
+    respond_to do |format|
+      format.turbo_stream
+    end
+  end
+
+  def destroy
+    @assistant.destroy
+    redirect_to assistants_path, notice: "Assistant was successfully deleted."
+  end
+
+  private
+
+  def set_assistant
+    @assistant = Assistant.find(params[:id])
+  end
+
+  def assistant_params
+    params.require(:assistant).permit(:name, :instructions, :tool_choice)
+  end
+end

lib/langchainrb_rails/generators/langchainrb_rails/templates/assistant/migrations/create_assistants.rb.tt

@@ -1,9 +1,10 @@
 class <%= migration_class_name %> < ActiveRecord::Migration<%= migration_version %>
   def change
     create_table :assistants do |t|
+      t.string :name, null: false
       t.string :instructions
       t.string :tool_choice
-      t.json :tools
+      t.json :tools, default: []
       t.timestamps
     end
   end

lib/langchainrb_rails/generators/langchainrb_rails/templates/assistant/migrations/create_messages.rb.tt

@@ -2,9 +2,9 @@ class <%= migration_class_name %> < ActiveRecord::Migration<%= migration_version
   def change
     create_table :messages do |t|
       t.references :assistant, foreign_key: true
-      t.string :role
+      t.string :role, null: false
       t.text :content
-      t.json :tool_calls
+      t.json :tool_calls, default: []
       t.string :tool_call_id
       t.timestamps
     end

lib/langchainrb_rails/generators/langchainrb_rails/templates/assistant/models/assistant.rb.tt

@@ -1,7 +1,11 @@
 # frozen_string_literal: true
 
 class Assistant < ActiveRecord::Base
-  has_many :messages
+has_many :messages, dependent: :destroy
+
+  validates :name, presence: true
+
+  # TODO: Validate tool_choice
 
   def llm
     <%= llm_class %>.new(api_key: ENV["<%= llm.upcase %>_API_KEY"])

lib/langchainrb_rails/generators/langchainrb_rails/templates/assistant/models/message.rb.tt

@@ -2,4 +2,6 @@
 
 class Message < ActiveRecord::Base
   belongs_to :assistant
+
+  validates :role, presence: true
 end