Support v1/responses and use harmony in serving_chat (#8837)

Signed-off-by: Xinyuan Tong <justinning0323@outlook.com>
Signed-off-by: Xinyuan Tong <xinyuantong.cs@gmail.com>
Co-authored-by: Xinyuan Tong <justinning0323@outlook.com>
Co-authored-by: Xinyuan Tong <xinyuantong.cs@gmail.com>

python/sglang/srt/function_call/harmony_tool_parser.py

@@ -0,0 +1,130 @@
+# Copyright 2023-2024 SGLang Team
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# ==============================================================================
+"""Harmony tool call parser for processing tool calls in harmony models."""
+
+import uuid
+from typing import List, Optional, Tuple
+
+from sglang.srt.entrypoints.openai.protocol import (
+    ChatMessage,
+    FunctionResponse,
+    ToolCall,
+)
+
+
+class HarmonyToolCallParser:
+    """Parser for extracting tool calls from harmony model outputs."""
+
+    def extract_tool_calls_from_message(self, msg) -> Optional[ToolCall]:
+        """
+        Extract tool call from a single message if it's a tool call.
+
+        Args:
+            msg: The harmony message
+
+        Returns:
+            ToolCall if the message is a tool call, None otherwise
+        """
+        if (
+            msg.channel == "commentary"
+            and msg.recipient
+            and msg.recipient.startswith("functions.")
+        ):
+            function_name = msg.recipient.split(".")[-1]
+            arguments = msg.content[0].text if msg.content else "{}"
+
+            return ToolCall(
+                id=f"call_{uuid.uuid4().hex[:24]}",
+                function=FunctionResponse(
+                    name=function_name,
+                    arguments=arguments,
+                ),
+            )
+        return None
+
+    def process_streaming_chunk(
+        self,
+        harmony_parser,
+        index: int,
+        tool_call_trackers: dict,
+        stream_buffers: dict,
+    ) -> Tuple[Optional[dict], bool, Optional[str]]:
+        """
+        Process a streaming chunk for tool calls.
+
+        Args:
+            harmony_parser: The harmony parser instance
+            index: The choice index
+            tool_call_trackers: Dict tracking tool calls per choice
+            stream_buffers: Dict for buffering content
+
+        Returns:
+            Tuple of (tool_call_data, is_tool_call, delta)
+        """
+        # Check if we're in a tool call
+        is_tool_call = (
+            harmony_parser.current_channel == "commentary"
+            and harmony_parser.current_recipient
+            and harmony_parser.current_recipient.startswith("functions.")
+        )
+
+        delta = harmony_parser.last_content_delta or ""
+        tool_call_data = None
+
+        if is_tool_call:
+            # Handle tool call streaming
+            function_name = harmony_parser.current_recipient.split(".")[-1]
+
+            # Track tool call indices per choice
+            if index not in tool_call_trackers:
+                tool_call_trackers[index] = {"count": 0, "current_function": None}
+
+            # Check if we just started a new tool call
+            tool_call_tracker = tool_call_trackers[index]
+            if tool_call_tracker["current_function"] != function_name:
+                # New tool call started
+                tool_call_tracker["current_function"] = function_name
+                tool_call_index = tool_call_tracker["count"]
+                tool_call_tracker["count"] += 1
+
+                # Store the tool call index for this function
+                tool_call_key = f"{index}_{function_name}"
+                stream_buffers[tool_call_key] = {
+                    "index": tool_call_index,
+                    "content": "",
+                }
+
+                tool_call_data = {
+                    "id": f"call_{uuid.uuid4().hex[:24]}",
+                    "index": tool_call_index,
+                    "function_name": function_name,
+                    "arguments": delta,
+                    "is_first_chunk": True,
+                }
+            else:
+                # Subsequent chunks for the same tool call
+                tool_call_key = f"{index}_{function_name}"
+                tool_call_index = stream_buffers[tool_call_key]["index"]
+
+                tool_call_data = {
+                    "id": None,
+                    "index": tool_call_index,
+                    "function_name": None,
+                    "arguments": delta,
+                    "is_first_chunk": False,
+                }
+
+            stream_buffers[tool_call_key]["content"] += delta
+
+        return tool_call_data, is_tool_call, delta