main: 增强会话功能，支持归档与消息检索

- 添加会话归档接口及相关服务逻辑，并确保幂等性 - 实现单条消息获取接口，校验消息所属会话 - 增加 SSE 增量推送与实时消息订阅功能 - 提供相关的测试用例覆盖新功能 - 更新接口文档，完善 OpenAPI 规范，新增多项示例
2025-12-14 21:58:05 +08:00
parent 6356baacc0
commit 318571a6d9
7 changed files with 531 additions and 47 deletions
--- a/app/Http/Controllers/ChatSessionSseController.php
+++ b/app/Http/Controllers/ChatSessionSseController.php
@@ -0,0 +1,110 @@
+<?php
+
+namespace App\Http\Controllers;
+
+use App\Http\Resources\MessageResource;
+use App\Services\ChatService;
+use Illuminate\Http\Request;
+use Illuminate\Http\Response;
+use Illuminate\Support\Facades\Redis;
+use Symfony\Component\HttpFoundation\StreamedResponse;
+
+class ChatSessionSseController extends Controller
+{
+    public function __construct(private readonly ChatService $service)
+    {
+    }
+
+    public function stream(Request $request, string $sessionId): Response|StreamedResponse
+    {
+        $this->service->getSession($sessionId); // ensure exists
+
+        $lastEventId = $request->header('Last-Event-ID');
+        $afterSeq = is_numeric($lastEventId) ? (int) $lastEventId : (int) $request->query('after_seq', 0);
+        $limit = (int) $request->query('limit', 200);
+        $limit = $limit > 0 && $limit <= 500 ? $limit : 200;
+
+        if (app()->runningUnitTests() || app()->environment('testing') || ! class_exists(\Redis::class)) {
+            $lastSentSeq = $afterSeq;
+            ob_start();
+            $this->sendBacklog($sessionId, $lastSentSeq, $limit, false);
+            $content = ob_get_clean() ?: '';
+
+            return response($content, 200, [
+                'Content-Type' => 'text/event-stream',
+                'Cache-Control' => 'no-cache',
+                'X-Accel-Buffering' => 'no',
+            ]);
+        }
+
+        $response = new StreamedResponse(function () use ($sessionId, $afterSeq, $limit) {
+            $lastSentSeq = $afterSeq;
+
+            $this->sendBacklog($sessionId, $lastSentSeq, $limit);
+
+            $redis = Redis::connection()->client();
+            if (method_exists($redis, 'setOption')) {
+                $redis->setOption(\Redis::OPT_READ_TIMEOUT, 5);
+            }
+
+            $channel = "session:{$sessionId}:messages";
+            $pubSub = $redis->pubSubLoop();
+            $pubSub->subscribe($channel);
+            $lastPing = time();
+
+            foreach ($pubSub as $message) {
+                if ($message->kind === 'subscribe') {
+                    continue;
+                }
+
+                if (connection_aborted()) {
+                    $pubSub->unsubscribe();
+                    break;
+                }
+
+                $payloadId = $message->payload ?? null;
+                if ($payloadId) {
+                    $msg = $this->service->getMessage($sessionId, $payloadId);
+                    if ($msg && $msg->seq > $lastSentSeq) {
+                        $this->emitMessage($msg);
+                        $lastSentSeq = $msg->seq;
+                    }
+                }
+
+                if (time() - $lastPing >= 20) {
+                    echo ": ping\n\n";
+                    @ob_flush();
+                    @flush();
+                    $lastPing = time();
+                }
+            }
+        });
+
+        $response->headers->set('Content-Type', 'text/event-stream');
+        $response->headers->set('Cache-Control', 'no-cache');
+        $response->headers->set('X-Accel-Buffering', 'no');
+
+        return $response;
+    }
+
+    private function sendBacklog(string $sessionId, int &$lastSentSeq, int $limit, bool $flush = true): void
+    {
+        $backlog = $this->service->listMessagesBySeq($sessionId, $lastSentSeq, $limit);
+        foreach ($backlog as $message) {
+            $this->emitMessage($message, $flush);
+            $lastSentSeq = $message->seq;
+        }
+    }
+
+    private function emitMessage($message, bool $flush = true): void
+    {
+        $payload = (new MessageResource($message))->resolve();
+        echo 'id: '.$message->seq."\n";
+        echo "event: message\n";
+        echo 'data: '.json_encode($payload, JSON_UNESCAPED_UNICODE)."\n\n";
+        if ($flush) {
+            @ob_flush();
+            @flush();
+        }
+    }
+}