Implement StepFun Realtime service and enhance AssistantConfig

- Add new fields to AssistantConfig for realtime interface configuration, including types, values, and secrets.
- Introduce StepFunRealtimeService to handle speech-to-speech processing via WebSocket, integrating STT, LLM, and TTS functionalities.
- Refactor pipeline execution to support a new realtime mode, allowing direct text input processing and immediate responses.
- Update model resource testing to include validation for StepFun Realtime connections.
- Enhance service factory to create realtime services based on configuration settings.
- Modify README documentation to reflect new realtime capabilities and usage instructions.

backend/services/model_resource_tester.py

@@ -2,11 +2,15 @@
 
 from __future__ import annotations
 
+import asyncio
 import io
+import json
 import time
 import wave
+from urllib.parse import parse_qsl, urlencode, urlsplit, urlunsplit
 
 import httpx
+from websockets.asyncio.client import connect as websocket_connect
 
 import config
 from schemas import ModelResourceTestResult
@@ -57,6 +61,8 @@ async def test_model_resource(
             message="讯飞连接参数有效",
             detail="鉴权字段和连接参数完整，请在语音测试页验证签名及音频链路",
         )
+    if interface_type == "stepfun-realtime":
+        return await _test_stepfun_realtime(values, secrets)
     if capability == "Realtime":
         return ModelResourceTestResult(
             ok=False,
@@ -150,3 +156,61 @@ async def test_model_resource(
             message="无法连接到模型服务",
             detail=str(exc)[:300],
         )
+
+
+async def _test_stepfun_realtime(
+    values: dict, secrets: dict
+) -> ModelResourceTestResult:
+    api_url = str(values.get("apiUrl") or "")
+    model_id = str(values.get("modelId") or "")
+    api_key = str(secrets.get("apiKey") or "")
+    parts = urlsplit(api_url)
+    query = dict(parse_qsl(parts.query))
+    query["model"] = model_id
+    url = urlunsplit(
+        (parts.scheme, parts.netloc, parts.path, urlencode(query), parts.fragment)
+    )
+    started = time.perf_counter()
+
+    try:
+        async with websocket_connect(
+            url,
+            additional_headers={"Authorization": f"Bearer {api_key}"},
+            open_timeout=TEST_TIMEOUT_SECONDS,
+            close_timeout=2,
+        ) as websocket:
+            raw_message = await asyncio.wait_for(
+                websocket.recv(), timeout=TEST_TIMEOUT_SECONDS
+            )
+            event = json.loads(raw_message)
+            if event.get("type") != "session.created":
+                return ModelResourceTestResult(
+                    ok=False,
+                    latency_ms=round((time.perf_counter() - started) * 1000),
+                    message="Realtime 连接返回了意外事件",
+                    detail=str(event.get("type") or event)[:300],
+                )
+        return ModelResourceTestResult(
+            ok=True,
+            latency_ms=round((time.perf_counter() - started) * 1000),
+            message="Realtime 连接成功",
+            detail="StepFun 返回 session.created",
+        )
+    except TimeoutError:
+        return ModelResourceTestResult(
+            ok=False,
+            latency_ms=round((time.perf_counter() - started) * 1000),
+            message="Realtime 连接超时",
+            detail=f"服务未在 {TEST_TIMEOUT_SECONDS:g} 秒内创建 session",
+        )
+    except Exception as exc:
+        detail = str(exc)
+        for secret in secrets.values():
+            if secret:
+                detail = detail.replace(str(secret), "***")
+        return ModelResourceTestResult(
+            ok=False,
+            latency_ms=round((time.perf_counter() - started) * 1000),
+            message="无法连接到 StepFun Realtime",
+            detail=detail[:300],
+        )