feat(Tool Calling): Support required and specific function mode (#6550)

python/sglang/srt/function_call/utils.py

@@ -0,0 +1,35 @@
+import json
+from json import JSONDecodeError, JSONDecoder
+from typing import Any, Tuple
+
+import partial_json_parser
+from partial_json_parser.core.options import Allow
+
+
+def _find_common_prefix(s1: str, s2: str) -> str:
+    prefix = ""
+    min_length = min(len(s1), len(s2))
+    for i in range(0, min_length):
+        if s1[i] == s2[i]:
+            prefix += s1[i]
+        else:
+            break
+    return prefix
+
+
+def _partial_json_loads(input_str: str, flags: Allow) -> Tuple[Any, int]:
+    try:
+        return (partial_json_parser.loads(input_str, flags), len(input_str))
+    except JSONDecodeError as e:
+        if "Extra data" in e.msg:
+            dec = JSONDecoder()
+            return dec.raw_decode(input_str)
+        raise
+
+
+def _is_complete_json(input_str: str) -> bool:
+    try:
+        json.loads(input_str)
+        return True
+    except JSONDecodeError:
+        return False