chore: update gitignore; feat: 新增customer_agent业务模块与api路由

rag/generation.py

@@ -0,0 +1,42 @@
+"""LLM answer generation with the客服 Agent fallback chain."""
+from __future__ import annotations
+
+import logging
+from inspect import isawaitable
+
+
+logger = logging.getLogger("rag.generation")
+
+
+async def _config(config_getter, key: str, default=None):
+    value = config_getter(key, default)
+    if isawaitable(value):
+        value = await value
+    return value
+
+
+async def generate_answer(
+    messages: list[dict],
+    *,
+    llm_client,
+    config_getter,
+    primary_model: str | None = None,
+) -> str:
+    fallback_model = await _config(
+        config_getter, "agent.customer.llm.fallback_model", ""
+    )
+    template = await _config(
+        config_getter, "agent.customer.template.system_busy", None
+    )
+    models = [primary_model] if primary_model else [None]
+    if fallback_model and fallback_model not in models:
+        models.append(fallback_model)
+    for model in models:
+        try:
+            kwargs = {} if model is None else {"model": model}
+            return await llm_client.chat(messages, **kwargs)
+        except Exception:
+            logger.exception("LLM generation failed for model=%s", model or "default")
+    if not template:
+        raise RuntimeError("system busy template is not configured")
+    return template