Add example demonstrating usage of OpenAI streaming results with token usage stats

Author: oesteve

examples/openai/toolcall-stream-with-usage.php

@@ -0,0 +1,65 @@
+<?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\Agent\Toolbox\AgentProcessor;
+use Symfony\AI\Agent\Toolbox\Tool\Clock;
+use Symfony\AI\Agent\Toolbox\Toolbox;
+use Symfony\AI\Platform\Bridge\OpenAi\PlatformFactory;
+use Symfony\AI\Platform\Bridge\OpenAi\TokenOutputProcessor;
+use Symfony\AI\Platform\Message\Message;
+use Symfony\AI\Platform\Message\MessageBag;
+use Symfony\AI\Platform\Result\TextChunk;
+
+require_once dirname(__DIR__).'/bootstrap.php';
+
+$platform = PlatformFactory::create(env('OPENAI_API_KEY'), http_client());
+
+$clock = new Clock();
+$openMeteo = new Symfony\AI\Agent\Toolbox\Tool\OpenMeteo(http_client());
+$toolbox = new Toolbox([$clock, $openMeteo], logger: logger());
+$processor = new AgentProcessor($toolbox);
+
+$tokenOutputProcessor = new TokenOutputProcessor();
+
+$agent = new Agent($platform, 'gpt-4o-mini', [$processor], [$processor]);
+$messages = new MessageBag(Message::ofUser(<<<TXT
+    Tell me the time and the weather in Dublin.
+    TXT));
+$result = $agent->call($messages, [
+    'stream' => true, // enable streaming of response text
+    'stream_options' => [
+        'include_usage' => true, // include usage in the response
+    ],
+]);
+
+// Output text chunks
+/** @var TextChunk $textChunk */
+foreach ($result->getContent() as $textChunk) {
+
+    // $textChunk implement \Stringable
+    echo $textChunk->getContent();
+
+    // Chunk also contain metadata
+    // $textChunk->getMetadata()->get('id'); // Stream id
+}
+
+// Output token usage statistics for each call
+foreach ($result->getMetadata()->get('calls', []) as $call) {
+    echo \PHP_EOL.sprintf(
+        '%s: %d tokens - Finish reason: [%s]',
+        $call['id'],
+        $call['usage']['total_tokens'],
+        $call['finish_reason']
+    );
+}
+
+echo \PHP_EOL;