Add Perplexity streamed response support

Author: welcoMattic

examples/perplexity/stream.php

@@ -0,0 +1,70 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+use Symfony\AI\Agent\Agent;
+use Symfony\AI\Platform\Bridge\Perplexity\Perplexity;
+use Symfony\AI\Platform\Bridge\Perplexity\PlatformFactory;
+use Symfony\AI\Platform\Bridge\Perplexity\SearchResultProcessor;
+use Symfony\AI\Platform\Bridge\Perplexity\TokenOutputProcessor;
+use Symfony\AI\Platform\Message\Message;
+use Symfony\AI\Platform\Message\MessageBag;
+
+require_once dirname(__DIR__) . '/bootstrap.php';
+
+$platform = PlatformFactory::create(env('PERPLEXITY_API_KEY'), http_client());
+$model = new Perplexity();
+$agent = new Agent($platform, $model, outputProcessors: [new TokenOutputProcessor(), new SearchResultProcessor()], logger: logger());
+
+$messages = new MessageBag(
+    Message::forSystem('You are a thoughtful philosopher.'),
+    Message::ofUser('What is the purpose of an ant?'),
+);
+$result = $agent->call($messages, [
+    'stream' => true,
+]);
+
+foreach ($result->getContent() as $word) {
+    echo $word;
+}
+echo \PHP_EOL;
+
+$metadata = $result->getMetadata();
+if ($metadata->has('search_results')) {
+    echo 'Search results:'.\PHP_EOL;
+    if (0 === count($metadata->get('search_results'))) {
+        echo 'No search results.'.\PHP_EOL;
+
+        return;
+    }
+    foreach ($metadata->get('search_results') as $i => $searchResult) {
+        echo 'Result #'.($i + 1).':'.\PHP_EOL;
+        echo $searchResult['title'].\PHP_EOL;
+        echo $searchResult['url'].\PHP_EOL;
+        echo $searchResult['date'].\PHP_EOL;
+        echo $searchResult['last_updated'] ? $searchResult['last_updated'].\PHP_EOL : '';
+        echo $searchResult['snippet'] ? $searchResult['snippet'].\PHP_EOL : '';
+        echo \PHP_EOL;
+    }
+}
+
+if ($metadata->has('citations')) {
+    echo 'Citations:'.\PHP_EOL;
+    if (0 === count($metadata->get('citations'))) {
+        echo 'No citations.'.\PHP_EOL;
+
+        return;
+    }
+    foreach ($metadata->get('citations') as $i => $citation) {
+        echo 'Citation #'.($i + 1).':'.\PHP_EOL;
+        echo $citation.\PHP_EOL;
+        echo \PHP_EOL;
+    }
+}

src/platform/src/Bridge/Perplexity/ResultConverter.php

@@ -12,6 +12,7 @@
 namespace Symfony\AI\Platform\Bridge\Perplexity;
 
 use Symfony\AI\Platform\Exception\RuntimeException;
+use Symfony\AI\Platform\Metadata\Metadata;
 use Symfony\AI\Platform\Model;
 use Symfony\AI\Platform\Result\ChoiceResult;
 use Symfony\AI\Platform\Result\RawHttpResult;
@@ -56,6 +57,10 @@ public function convert(RawResultInterface|RawHttpResult $result, array $options
 
     private function convertStream(HttpResponse $result): \Generator
     {
+        $searchResults = $citations = [];
+        /** @var Metadata $metadata */
+        $metadata = yield;
+
         foreach ((new EventSourceHttpClient())->stream($result) as $chunk) {
             if (!$chunk instanceof ServerSentEvent || '[DONE]' === $chunk->getData()) {
                 continue;
@@ -68,12 +73,21 @@ private function convertStream(HttpResponse $result): \Generator
                 continue;
             }
 
-            if (!isset($data['choices'][0]['delta']['content'])) {
-                continue;
+            if (isset($data['choices'][0]['delta']['content'])) {
+                yield $data['choices'][0]['delta']['content'];
+            }
+
+            if (isset($data['search_results'])) {
+                $searchResults = $data['search_results'];
             }
 
-            yield $data['choices'][0]['delta']['content'];
+            if (isset($data['citations'])) {
+                $citations = $data['citations'];
+            }
         }
+
+        $metadata->add('search_results', $searchResults);
+        $metadata->add('citations', $citations);
     }
 
     /**

src/platform/src/Bridge/Perplexity/SearchResultProcessor.php

@@ -23,8 +23,13 @@ final class SearchResultProcessor implements OutputProcessorInterface
 {
     public function processOutput(Output $output): void
     {
+        $metadata = $output->result->getMetadata();
+
         if ($output->result instanceof StreamResult) {
-            // @TODO
+            $generator = $output->result->getContent();
+            // Makes $metadata accessible in the stream loop.
+            $generator->send($metadata);
+
             return;
         }
 
@@ -33,7 +38,6 @@ public function processOutput(Output $output): void
             return;
         }
 
-        $metadata = $output->result->getMetadata();
         $content = $rawResponse->toArray(false);
 
         if (\array_key_exists('search_results', $content)) {

src/platform/src/Result/RawHttpResult.php

@@ -14,7 +14,7 @@
 use Symfony\Contracts\HttpClient\ResponseInterface;
 
 /**
- * @author Christopher Hertel <mail@christopher-hertel.de
+ * @author Christopher Hertel <mail@christopher-hertel.de>
  */
 final readonly class RawHttpResult implements RawResultInterface
 {