add missing messages endpoint

routstr/upstream/base.py

@@ -1098,6 +1098,174 @@ class BaseUpstreamProvider:
                     },
                 )
 
+    async def handle_streaming_messages_completion(
+        self, response: httpx.Response, key: ApiKey, max_cost_for_model: int
+    ) -> StreamingResponse:
+        async def stream_with_cost(
+            max_cost_for_model: int,
+        ) -> AsyncGenerator[bytes, None]:
+            stored_chunks: list[bytes] = []
+            usage_finalized: bool = False
+            last_model_seen: str | None = None
+            input_tokens: int = 0
+            output_tokens: int = 0
+
+            async def finalize_without_usage() -> bytes | None:
+                nonlocal usage_finalized
+                if usage_finalized:
+                    return None
+                async with create_session() as new_session:
+                    fresh_key = await new_session.get(key.__class__, key.hashed_key)
+                    if not fresh_key:
+                        usage_finalized = True
+                        return None
+                    try:
+                        fallback: dict = {
+                            "model": last_model_seen or "unknown",
+                            "usage": None,
+                        }
+                        cost_data = await adjust_payment_for_tokens(
+                            fresh_key, fallback, new_session, max_cost_for_model
+                        )
+                        usage_finalized = True
+                        return f"event: cost\ndata: {json.dumps({'cost': cost_data})}\n\n".encode()
+                    except Exception:
+                        usage_finalized = True
+                        return None
+
+            try:
+                async for chunk in response.aiter_bytes():
+                    stored_chunks.append(chunk)
+                    try:
+                        decoded_chunk = chunk.decode("utf-8", errors="ignore")
+                        for line in decoded_chunk.split("\n"):
+                            if line.startswith("data: "):
+                                try:
+                                    data = json.loads(line[6:])
+                                    if isinstance(data, dict):
+                                        msg = data.get("message", {})
+                                        if msg and msg.get("model"):
+                                            last_model_seen = str(msg.get("model"))
+
+                                        if usage := msg.get("usage"):
+                                            input_tokens += usage.get("input_tokens", 0)
+                                            output_tokens += usage.get(
+                                                "output_tokens", 0
+                                            )
+
+                                        if usage := data.get("usage"):
+                                            input_tokens += usage.get("input_tokens", 0)
+                                            output_tokens += usage.get(
+                                                "output_tokens", 0
+                                            )
+                                except json.JSONDecodeError:
+                                    pass
+                    except Exception:
+                        pass
+
+                    yield chunk
+
+                usage_data = {
+                    "input_tokens": input_tokens,
+                    "output_tokens": output_tokens,
+                }
+
+                if input_tokens > 0 or output_tokens > 0:
+                    async with create_session() as new_session:
+                        fresh_key = await new_session.get(key.__class__, key.hashed_key)
+                        if fresh_key:
+                            try:
+                                combined_data = {
+                                    "model": last_model_seen or "unknown",
+                                    "usage": usage_data,
+                                }
+                                cost_data = await adjust_payment_for_tokens(
+                                    fresh_key,
+                                    combined_data,
+                                    new_session,
+                                    max_cost_for_model,
+                                )
+                                usage_finalized = True
+                                yield f"event: cost\ndata: {json.dumps({'cost': cost_data})}\n\n".encode()
+                            except Exception:
+                                pass
+
+                if not usage_finalized:
+                    maybe_cost_event = await finalize_without_usage()
+                    if maybe_cost_event is not None:
+                        yield maybe_cost_event
+
+            except httpx.ReadError:
+                if not usage_finalized:
+                    await finalize_without_usage()
+                # Upstream dropped the connection mid-stream; response already started, swallow silently
+            except Exception:
+                if not usage_finalized:
+                    await finalize_without_usage()
+                raise
+            finally:
+                if not usage_finalized:
+                    await finalize_without_usage()
+
+        response_headers = dict(response.headers)
+        response_headers.pop("content-encoding", None)
+        response_headers.pop("content-length", None)
+
+        return StreamingResponse(
+            stream_with_cost(max_cost_for_model),
+            status_code=response.status_code,
+            headers=response_headers,
+        )
+
+    async def handle_non_streaming_messages_completion(
+        self,
+        response: httpx.Response,
+        key: ApiKey,
+        session: AsyncSession,
+        deducted_max_cost: int,
+        path: str,
+    ) -> Response:
+        try:
+            content = await response.aread()
+            response_json = json.loads(content)
+
+            if path.endswith("count_tokens") and "usage" not in response_json:
+                input_tokens = response_json.get("input_tokens", 0)
+                response_json["usage"] = {"input_tokens": input_tokens}
+
+            cost_data = await adjust_payment_for_tokens(
+                key, response_json, session, deducted_max_cost
+            )
+            response_json["cost"] = cost_data
+
+            allowed_headers = {
+                "content-type",
+                "cache-control",
+                "date",
+                "vary",
+                "access-control-allow-origin",
+                "access-control-allow-methods",
+                "access-control-allow-headers",
+                "access-control-allow-credentials",
+                "access-control-expose-headers",
+                "access-control-max-age",
+            }
+
+            response_headers = {
+                k: v
+                for k, v in response.headers.items()
+                if k.lower() in allowed_headers
+            }
+
+            return Response(
+                content=json.dumps(response_json).encode(),
+                status_code=response.status_code,
+                headers=response_headers,
+                media_type="application/json",
+            )
+        except Exception:
+            raise
+
     async def forward_request(
         self,
         request: Request,
@@ -1197,7 +1365,54 @@ class BaseUpstreamProvider:
                     await client.aclose()
                 return mapped_error
 
-            if path.endswith("chat/completions") or path.endswith("embeddings"):
+            if (
+                path.endswith("chat/completions")
+                or path.endswith("embeddings")
+                or path.endswith("messages")
+                or path.endswith("messages/count_tokens")
+            ):
+                if path.endswith("messages"):
+                    client_wants_streaming = False
+                    if request_body:
+                        try:
+                            request_data = json.loads(request_body)
+                            client_wants_streaming = request_data.get("stream", False)
+                        except json.JSONDecodeError:
+                            pass
+
+                    content_type = response.headers.get("content-type", "")
+                    upstream_is_streaming = "text/event-stream" in content_type
+                    is_streaming = client_wants_streaming and upstream_is_streaming
+
+                    if is_streaming and response.status_code == 200:
+                        result = await self.handle_streaming_messages_completion(
+                            response, key, max_cost_for_model
+                        )
+                        background_tasks = BackgroundTasks()
+                        background_tasks.add_task(response.aclose)
+                        background_tasks.add_task(client.aclose)
+                        result.background = background_tasks
+                        return result
+
+                    if response.status_code == 200:
+                        try:
+                            return await self.handle_non_streaming_messages_completion(
+                                response, key, session, max_cost_for_model, path
+                            )
+                        finally:
+                            await response.aclose()
+                            await client.aclose()
+
+                if path.endswith("messages/count_tokens"):
+                    if response.status_code == 200:
+                        try:
+                            return await self.handle_non_streaming_messages_completion(
+                                response, key, session, max_cost_for_model, path
+                            )
+                        finally:
+                            await response.aclose()
+                            await client.aclose()
+
                 if path.endswith("chat/completions"):
                     client_wants_streaming = False
                     if request_body:
@@ -1825,11 +2040,25 @@ class BaseUpstreamProvider:
             if line.startswith("data: "):
                 try:
                     data_json = json.loads(line[6:])
+                    # OpenAI format: usage and model at top level
                     if "usage" in data_json:
                         usage_data = data_json["usage"]
-                        model = data_json.get("model")
+                        model = data_json.get("model") or model
                     elif "model" in data_json and not model:
                         model = data_json["model"]
+                    # Anthropic format: model and input usage inside "message" key
+                    if "message" in data_json:
+                        msg = data_json["message"]
+                        if not model and msg.get("model"):
+                            model = msg["model"]
+                        if msg.get("usage") and not usage_data:
+                            usage_data = msg["usage"]
+                        elif msg.get("usage") and usage_data:
+                            # Merge: message_start has input_tokens, message_delta has output_tokens
+                            merged = dict(usage_data)
+                            for k, v in msg["usage"].items():
+                                merged[k] = merged.get(k, 0) + v
+                            usage_data = merged
                 except json.JSONDecodeError:
                     continue
 
@@ -2262,9 +2491,14 @@ class BaseUpstreamProvider:
                     error_response.headers["X-Cashu"] = refund_token
                     return error_response
 
-                if path.endswith("chat/completions") or path.endswith("embeddings"):
+                if (
+                    path.endswith("chat/completions")
+                    or path.endswith("embeddings")
+                    or path.endswith("messages")
+                    or path.endswith("messages/count_tokens")
+                ):
                     logger.debug(
-                        "Processing completion/embeddings response",
+                        "Processing completion/embeddings/messages response",
                         extra={"path": path, "amount": amount, "unit": unit},
                     )