bug #88 [AiBundle] Use model FQCN for indexer config, to allow any Symfony\AI\Platform\Model child class (welcoMattic)

This PR was merged into the main branch.

Discussion
----------

[AiBundle] Use model FQCN for indexer config, to allow any `Symfony\AI\Platform\Model` child class

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no <!-- please update src/**/CHANGELOG.md files -->
| Docs?         | no <!-- required for new features -->
| Issues        | Fix #59 <!-- prefix each issue number with "Fix #", no need to create an issue if none exist, explain below instead -->
| License       | MIT

Before:

```yaml
ai:
    indexer:
        default:
            platform: 'symfony_ai.platform.mistral'
            model:
                name: 'Embeddings'
                version: 'mistral-embed'

```

After

```yaml
ai:
    indexer:
        default:
            platform: 'symfony_ai.platform.mistral'
            model:
                class: 'Symfony\AI\Platform\Bridge\Mistral\Embeddings'
                name: !php/const Symfony\AI\Platform\Bridge\Mistral\Embeddings::MISTRAL_EMBED
```

This way, any class extending `Symfony\AI\Platform\Model` can be used as embedder model, even one written by users themselves.
Embeddings model of providers (OpenAI, Mistral, Gemini, ...) can be named `Embeddings` with no issue.

---

Replace php-llm/llm-chain-bundle#99

Commits
-------

66b6cbc Use model FQCN for indexer config, to allow any Symfony\AI\Platform\Model child class

Author: chr-hertel

demo/config/packages/ai.yaml

@@ -6,8 +6,8 @@ ai:
         blog:
             # platform: 'symfony_ai.platform.anthropic'
             model:
-                name: 'GPT'
-                version: 'gpt-4o-mini'
+                class: 'Symfony\AI\Platform\Bridge\OpenAI\GPT'
+                name: !php/const Symfony\AI\Platform\Bridge\OpenAI\GPT::GPT_4O_MINI
             tools:
                 - 'Symfony\AI\Agent\Toolbox\Tool\SimilaritySearch'
                 - service: 'clock'
@@ -16,13 +16,13 @@ ai:
                   method: 'now'
         youtube:
             model:
-                name: 'GPT'
-                version: 'gpt-4o-mini'
+                class: 'Symfony\AI\Platform\Bridge\OpenAI\GPT'
+                name: !php/const Symfony\AI\Platform\Bridge\OpenAI\GPT::GPT_4O_MINI
             tools: false
         wikipedia:
             model:
-                name: 'GPT'
-                version: 'gpt-4o-mini'
+                class: 'Symfony\AI\Platform\Bridge\OpenAI\GPT'
+                name: !php/const Symfony\AI\Platform\Bridge\OpenAI\GPT::GPT_4O_MINI
                 options:
                     temperature: 0.5
             system_prompt: 'Please answer the users question based on Wikipedia and provide a link to the article.'
@@ -31,8 +31,8 @@ ai:
                 - 'Symfony\AI\Agent\Toolbox\Tool\Wikipedia'
         audio:
             model:
-                name: 'GPT'
-                version: 'gpt-4o-mini'
+                class: 'Symfony\AI\Platform\Bridge\OpenAI\GPT'
+                name: !php/const Symfony\AI\Platform\Bridge\OpenAI\GPT::GPT_4O_MINI
             system_prompt: 'You are a friendly chatbot that likes to have a conversation with users and asks them some questions.'
             tools:
                 # Agent in agent 🤯
@@ -47,8 +47,8 @@ ai:
     indexer:
         default:
             model:
-                name: 'Embeddings'
-                version: 'text-embedding-ada-002'
+                class: 'Symfony\AI\Platform\Bridge\OpenAI\Embeddings'
+                name: !php/const Symfony\AI\Platform\Bridge\OpenAI\Embeddings::TEXT_ADA_002
 
 services:
     _defaults:

src/ai-bundle/config/options.php

@@ -70,8 +70,8 @@
                         ->end()
                         ->arrayNode('model')
                             ->children()
-                                ->scalarNode('name')->isRequired()->end()
-                                ->scalarNode('version')->defaultNull()->end()
+                                ->scalarNode('class')->isRequired()->end()
+                                ->scalarNode('name')->defaultNull()->end()
                                 ->arrayNode('options')
                                     ->variablePrototype()->end()
                                 ->end()
@@ -196,8 +196,8 @@
                         ->end()
                         ->arrayNode('model')
                             ->children()
-                                ->scalarNode('name')->isRequired()->end()
-                                ->scalarNode('version')->defaultNull()->end()
+                                ->scalarNode('class')->isRequired()->end()
+                                ->scalarNode('name')->defaultNull()->end()
                                 ->arrayNode('options')
                                     ->variablePrototype()->end()
                                 ->end()

src/ai-bundle/doc/index.rst

@@ -31,7 +31,8 @@ Configuration
         agent:
             default:
                 model:
-                    name: 'GPT'
+                    class: 'Symfony\AI\Platform\Bridge\OpenAI\GPT'
+                    name: !php/const Symfony\AI\Platform\Bridge\OpenAI\GPT::GPT_4O_MINI
 
 **Advanced Example with Anthropic, Azure, Google and multiple agents**
 
@@ -56,8 +57,8 @@ Configuration
                 platform: 'symfony_ai.platform.azure.gpt_deployment'
                 structured_output: false # Disables support for "output_structure" option, default is true
                 model:
-                    name: 'GPT'
-                    version: 'gpt-4o-mini'
+                    class: 'Symfony\AI\Platform\Bridge\OpenAI\GPT'
+                    name: !php/const Symfony\AI\Platform\Bridge\OpenAI\GPT::GPT_4O_MINI
                 system_prompt: 'You are a helpful assistant that can answer questions.' # The default system prompt of the agent
                 include_tools: true # Include tool definitions at the end of the system prompt
                 tools:
@@ -78,7 +79,8 @@ Configuration
             research:
                 platform: 'symfony_ai.platform.anthropic'
                 model:
-                    name: 'Claude'
+                    class: 'Symfony\AI\Platform\Bridge\Anthropic\Claude'
+                    name: !php/const Symfony\AI\Platform\Bridge\Anthropic\Claude::SONNET_37
                 tools: # If undefined, all tools are injected into the agent, use "tools: false" to disable tools.
                     - 'Symfony\AI\Agent\Toolbox\Tool\Wikipedia'
                 fault_tolerant_toolbox: false # Disables fault tolerant toolbox, default is true
@@ -90,11 +92,11 @@ Configuration
                     collection: 'my_collection'
         indexer:
             default:
-                # platform: 'symfony_ai.platform.anthropic'
+                # platform: 'symfony_ai.platform.mistral'
                 # store: 'symfony_ai.store.chroma_db.default'
                 model:
-                    name: 'Embeddings'
-                    version: 'text-embedding-ada-002'
+                    class: 'Symfony\AI\Platform\Bridge\Mistral\Embeddings'
+                    name: !php/const Symfony\AI\Platform\Bridge\Mistral\Embeddings::MISTRAL_EMBED
 
 Usage
 -----

src/ai-bundle/src/AIBundle.php

@@ -27,19 +27,12 @@
 use Symfony\AI\AIBundle\Profiler\DataCollector;
 use Symfony\AI\AIBundle\Profiler\TraceablePlatform;
 use Symfony\AI\AIBundle\Profiler\TraceableToolbox;
-use Symfony\AI\Platform\Bridge\Anthropic\Claude;
 use Symfony\AI\Platform\Bridge\Anthropic\PlatformFactory as AnthropicPlatformFactory;
 use Symfony\AI\Platform\Bridge\Azure\OpenAI\PlatformFactory as AzureOpenAIPlatformFactory;
-use Symfony\AI\Platform\Bridge\Google\Gemini;
 use Symfony\AI\Platform\Bridge\Google\PlatformFactory as GooglePlatformFactory;
-use Symfony\AI\Platform\Bridge\Meta\Llama;
-use Symfony\AI\Platform\Bridge\Mistral\Mistral;
 use Symfony\AI\Platform\Bridge\Mistral\PlatformFactory as MistralPlatformFactory;
-use Symfony\AI\Platform\Bridge\OpenAI\Embeddings;
-use Symfony\AI\Platform\Bridge\OpenAI\GPT;
 use Symfony\AI\Platform\Bridge\OpenAI\PlatformFactory as OpenAIPlatformFactory;
 use Symfony\AI\Platform\Bridge\OpenRouter\PlatformFactory as OpenRouterPlatformFactory;
-use Symfony\AI\Platform\Bridge\Voyage\Voyage;
 use Symfony\AI\Platform\Model;
 use Symfony\AI\Platform\ModelClientInterface;
 use Symfony\AI\Platform\Platform;
@@ -261,20 +254,15 @@ private function processPlatformConfig(string $type, array $platform, ContainerB
     private function processAgentConfig(string $name, array $config, ContainerBuilder $container): void
     {
         // MODEL
-        ['name' => $modelName, 'version' => $version, 'options' => $options] = $config['model'];
-
-        $modelClass = match (strtolower((string) $modelName)) {
-            'gpt' => GPT::class,
-            'claude' => Claude::class,
-            'llama' => Llama::class,
-            'gemini' => Gemini::class,
-            'mistral' => Mistral::class,
-            'openrouter' => Model::class,
-            default => throw new \InvalidArgumentException(\sprintf('Model "%s" is not supported.', $modelName)),
-        };
+        ['class' => $modelClass, 'name' => $modelName, 'options' => $options] = $config['model'];
+
+        if (!is_a($modelClass, Model::class, true)) {
+            throw new \InvalidArgumentException(\sprintf('"%s" class is not extending Symfony\AI\Platform\Model.', $modelClass));
+        }
+
         $modelDefinition = new Definition($modelClass);
-        if (null !== $version) {
-            $modelDefinition->setArgument('$name', $version);
+        if (null !== $modelName) {
+            $modelDefinition->setArgument('$name', $modelName);
         }
         if ([] !== $options) {
             $modelDefinition->setArgument('$options', $options);
@@ -473,20 +461,20 @@ private function processStoreConfig(string $type, array $stores, ContainerBuilde
      */
     private function processIndexerConfig(int|string $name, array $config, ContainerBuilder $container): void
     {
-        ['name' => $modelName, 'version' => $version, 'options' => $options] = $config['model'];
-
-        $modelClass = match (strtolower((string) $modelName)) {
-            'embeddings' => Embeddings::class,
-            'voyage' => Voyage::class,
-            default => throw new \InvalidArgumentException(\sprintf('Model "%s" is not supported.', $modelName)),
-        };
-        $modelDefinition = (new Definition($modelClass));
-        if (null !== $version) {
-            $modelDefinition->setArgument('$name', $version);
+        ['class' => $modelClass, 'name' => $modelName, 'options' => $options] = $config['model'];
+
+        if (!is_a($modelClass, Model::class, true)) {
+            throw new \InvalidArgumentException(\sprintf('"%s" class is not extending Symfony\AI\Platform\Model.', $modelClass));
+        }
+
+        $modelDefinition = (new Definition((string) $modelClass));
+        if (null !== $modelName) {
+            $modelDefinition->setArgument('$name', $modelName);
         }
         if ([] !== $options) {
             $modelDefinition->setArgument('$options', $options);
         }
+
         $modelDefinition->addTag('symfony_ai.model.embeddings_model');
         $container->setDefinition('symfony_ai.indexer.'.$name.'.model', $modelDefinition);
 

src/ai-bundle/tests/AIBundleTest.php renamed to src/ai-bundle/tests/DependencyInjection/AIBundleTest.php

@@ -77,8 +77,8 @@ private function getFullConfig(): array
                     'my_chat_agent' => [
                         'platform' => 'openai_platform_service_id',
                         'model' => [
-                            'name' => 'gpt',
-                            'version' => 'gpt-3.5-turbo',
+                            'class' => 'Symfony\AI\Platform\Bridge\OpenAI\GPT',
+                            'name' => 'gpt-3.5-turbo',
                             'options' => [
                                 'temperature' => 0.7,
                                 'max_tokens' => 150,
@@ -98,7 +98,7 @@ private function getFullConfig(): array
                         'fault_tolerant_toolbox' => false,
                     ],
                     'another_agent' => [
-                        'model' => ['name' => 'claude', 'version' => 'claude-3-opus-20240229'],
+                        'model' => ['class' => 'Symfony\AI\Platform\Bridge\Anthropic\Claude', 'name' => 'claude-3-opus-20240229'],
                         'system_prompt' => 'Be concise.',
                     ],
                 ],
@@ -137,10 +137,10 @@ private function getFullConfig(): array
                 'indexer' => [
                     'my_text_indexer' => [
                         'store' => 'my_azure_search_store_service_id',
-                        'platform' => 'google_platform_service_id',
+                        'platform' => 'mistral_platform_service_id',
                         'model' => [
-                            'name' => 'embeddings',
-                            'version' => 'text-embedding-004',
+                            'class' => 'Symfony\AI\Platform\Bridge\Mistral\Embeddings',
+                            'name' => 'mistral-embed',
                             'options' => ['dimension' => 768],
                         ],
                     ],