Allow user to define whitespace pattern for outlines (#4305)

tests/entrypoints/test_guided_processors.py

@@ -57,7 +57,9 @@ def test_guided_logits_processors():
     """Basic unit test for RegexLogitsProcessor and JSONLogitsProcessor."""
     tokenizer = AutoTokenizer.from_pretrained('HuggingFaceH4/zephyr-7b-beta')
     regex_LP = RegexLogitsProcessor(TEST_REGEX, tokenizer)
-    json_LP = JSONLogitsProcessor(TEST_SCHEMA, tokenizer)
+    json_LP = JSONLogitsProcessor(TEST_SCHEMA,
+                                  tokenizer,
+                                  whitespace_pattern=None)
 
     regex_LP.init_state()
     token_ids = tokenizer.encode(

vllm/entrypoints/openai/protocol.py

@@ -146,6 +146,11 @@ class ChatCompletionRequest(OpenAIBaseModel):
             "If specified, will override the default guided decoding backend "
             "of the server for this specific request. If set, must be either "
             "'outlines' / 'lm-format-enforcer'"))
+    guided_whitespace_pattern: Optional[str] = Field(
+        default=None,
+        description=(
+            "If specified, will override the default whitespace pattern "
+            "for guided json decoding."))
 
     # doc: end-chat-completion-extra-params
 
@@ -285,6 +290,11 @@ class CompletionRequest(OpenAIBaseModel):
             "If specified, will override the default guided decoding backend "
             "of the server for this specific request. If set, must be one of "
             "'outlines' / 'lm-format-enforcer'"))
+    guided_whitespace_pattern: Optional[str] = Field(
+        default=None,
+        description=(
+            "If specified, will override the default whitespace pattern "
+            "for guided json decoding."))
 
     # doc: end-completion-extra-params
 

vllm/model_executor/guided_decoding/outlines_decoding.py

@@ -74,7 +74,8 @@ async def get_outlines_guided_decoding_logits_processor(
 
     result = await loop.run_in_executor(global_thread_pool,
                                         _get_cached_logits_processor, guide,
-                                        tokenizer, mode)
+                                        tokenizer, mode,
+                                        request.guided_whitespace_pattern)
 
     logits_processor = copy(result)
     # reset logits processor's internal state
@@ -117,9 +118,10 @@ def _get_guide_and_mode(
 @lru_cache(maxsize=32)
 def _get_cached_logits_processor(guide: str,
                                  tokenizer: PreTrainedTokenizerBase,
-                                 mode: GuidedDecodingMode):
+                                 mode: GuidedDecodingMode,
+                                 whitespace_pattern: Union[str, None]):
     if mode == GuidedDecodingMode.JSON:
-        return JSONLogitsProcessor(guide, tokenizer)
+        return JSONLogitsProcessor(guide, tokenizer, whitespace_pattern)
     elif mode == GuidedDecodingMode.REGEX or mode == GuidedDecodingMode.CHOICE:
         return RegexLogitsProcessor(guide, tokenizer)
     elif mode == GuidedDecodingMode.GRAMMAR:

vllm/model_executor/guided_decoding/outlines_logits_processors.py

@@ -18,7 +18,7 @@ import json
 import math
 from collections import defaultdict
 from functools import lru_cache
-from typing import Callable, DefaultDict, Dict, List, Optional, Union
+from typing import Callable, DefaultDict, Dict, List, Union
 
 import torch
 from outlines.fsm.fsm import CFGFSM, FSM, RegexFSM
@@ -80,10 +80,9 @@ class RegexLogitsProcessor(BaseLogitsProcessor):
 
 class JSONLogitsProcessor(RegexLogitsProcessor):
 
-    def __init__(self,
-                 schema: Union[str, Dict, BaseModel],
+    def __init__(self, schema: Union[str, Dict, BaseModel],
                  tokenizer: PreTrainedTokenizerBase,
-                 whitespace_pattern: Optional[str] = None):
+                 whitespace_pattern: Union[str, None]):
         """Compile the FSM that drives the JSON-guided generation.
 
         Parameters