init

backend/app/services/gemini_client.py

@@ -0,0 +1,126 @@
+from google import genai
+from google.genai import types
+
+from backend.app.core.config import settings
+
+_client: genai.Client | None = None
+
+
+def get_client() -> genai.Client:
+    global _client
+    if _client is None:
+        _client = genai.Client(api_key=settings.GEMINI_API_KEY)
+    return _client
+
+
+def chat_sync(
+    messages: list[dict[str, str]],
+    system_instruction: str | None = None,
+    temperature: float = 0.7,
+    max_tokens: int = 8192,
+) -> str:
+    """
+    Synchronous chat with Gemini.
+
+    messages: list of {"role": "user"|"model", "text": "..."}
+    Returns the model's text response.
+    """
+    client = get_client()
+
+    contents = [
+        types.Content(
+            role=m["role"],
+            parts=[types.Part.from_text(text=m["text"])],
+        )
+        for m in messages
+    ]
+
+    config = types.GenerateContentConfig(
+        temperature=temperature,
+        max_output_tokens=max_tokens,
+    )
+    if system_instruction:
+        config.system_instruction = system_instruction
+
+    response = client.models.generate_content(
+        model=settings.GEMINI_MODEL,
+        contents=contents,
+        config=config,
+    )
+
+    return response.text or ""
+
+
+async def chat_async(
+    messages: list[dict[str, str]],
+    system_instruction: str | None = None,
+    temperature: float = 0.7,
+    max_tokens: int = 8192,
+) -> str:
+    """
+    Async chat with Gemini.
+
+    messages: list of {"role": "user"|"model", "text": "..."}
+    Returns the model's text response.
+    """
+    client = get_client()
+
+    contents = [
+        types.Content(
+            role=m["role"],
+            parts=[types.Part.from_text(text=m["text"])],
+        )
+        for m in messages
+    ]
+
+    config = types.GenerateContentConfig(
+        temperature=temperature,
+        max_output_tokens=max_tokens,
+    )
+    if system_instruction:
+        config.system_instruction = system_instruction
+
+    response = await client.aio.models.generate_content(
+        model=settings.GEMINI_MODEL,
+        contents=contents,
+        config=config,
+    )
+
+    return response.text or ""
+
+
+async def chat_stream(
+    messages: list[dict[str, str]],
+    system_instruction: str | None = None,
+    temperature: float = 0.7,
+    max_tokens: int = 8192,
+):
+    """
+    Async streaming chat with Gemini. Yields text chunks.
+
+    messages: list of {"role": "user"|"model", "text": "..."}
+    """
+    client = get_client()
+
+    contents = [
+        types.Content(
+            role=m["role"],
+            parts=[types.Part.from_text(text=m["text"])],
+        )
+        for m in messages
+    ]
+
+    config = types.GenerateContentConfig(
+        temperature=temperature,
+        max_output_tokens=max_tokens,
+    )
+    if system_instruction:
+        config.system_instruction = system_instruction
+
+    async for chunk in client.aio.models.generate_content_stream(
+        model=settings.GEMINI_MODEL,
+        contents=contents,
+        config=config,
+    ):
+        if chunk.text:
+            yield chunk.text