[V0 Deprecation] Remove Prompt Adapters (#20588)

Signed-off-by: mgoin <mgoin64@gmail.com>

vllm/engine/arg_utils.py

@@ -30,9 +30,9 @@ from vllm.config import (BlockSize, CacheConfig, CacheDType, CompilationConfig,
                          LogprobsMode, LoRAConfig, ModelConfig, ModelDType,
                          ModelImpl, MultiModalConfig, ObservabilityConfig,
                          ParallelConfig, PoolerConfig, PrefixCachingHashAlgo,
-                         PromptAdapterConfig, SchedulerConfig, SchedulerPolicy,
-                         SpeculativeConfig, TaskOption, TokenizerMode,
-                         VllmConfig, get_attr_docs, get_field)
+                         SchedulerConfig, SchedulerPolicy, SpeculativeConfig,
+                         TaskOption, TokenizerMode, VllmConfig, get_attr_docs,
+                         get_field)
 from vllm.logger import init_logger
 from vllm.platforms import CpuArchEnum, current_platform
 from vllm.plugins import load_general_plugins
@@ -358,11 +358,6 @@ class EngineArgs:
     max_cpu_loras: Optional[int] = LoRAConfig.max_cpu_loras
     lora_dtype: Optional[Union[str, torch.dtype]] = LoRAConfig.lora_dtype
     lora_extra_vocab_size: int = LoRAConfig.lora_extra_vocab_size
-    # PromptAdapter fields
-    enable_prompt_adapter: bool = False
-    max_prompt_adapters: int = PromptAdapterConfig.max_prompt_adapters
-    max_prompt_adapter_token: int = \
-        PromptAdapterConfig.max_prompt_adapter_token
 
     num_scheduler_steps: int = SchedulerConfig.num_scheduler_steps
     multi_step_stream_outputs: bool = SchedulerConfig.multi_step_stream_outputs
@@ -437,6 +432,8 @@ class EngineArgs:
         ParallelConfig.enable_multimodal_encoder_data_parallel
 
     async_scheduling: bool = SchedulerConfig.async_scheduling
+    # DEPRECATED
+    enable_prompt_adapter: bool = False
 
     def __post_init__(self):
         # support `EngineArgs(compilation_config={...})`
@@ -729,23 +726,6 @@ class EngineArgs:
         lora_group.add_argument("--default-mm-loras",
                                 **lora_kwargs["default_mm_loras"])
 
-        # PromptAdapter related configs
-        prompt_adapter_kwargs = get_kwargs(PromptAdapterConfig)
-        prompt_adapter_group = parser.add_argument_group(
-            title="PromptAdapterConfig",
-            description=PromptAdapterConfig.__doc__,
-        )
-        prompt_adapter_group.add_argument(
-            "--enable-prompt-adapter",
-            action=argparse.BooleanOptionalAction,
-            help="If True, enable handling of PromptAdapters.")
-        prompt_adapter_group.add_argument(
-            "--max-prompt-adapters",
-            **prompt_adapter_kwargs["max_prompt_adapters"])
-        prompt_adapter_group.add_argument(
-            "--max-prompt-adapter-token",
-            **prompt_adapter_kwargs["max_prompt_adapter_token"])
-
         # Speculative arguments
         speculative_group = parser.add_argument_group(
             title="SpeculativeConfig",
@@ -850,6 +830,12 @@ class EngineArgs:
         parser.add_argument('--disable-log-stats',
                             action='store_true',
                             help='Disable logging statistics.')
+        parser.add_argument('--enable-prompt-adapter',
+                            action='store_true',
+                            deprecated=True,
+                            help='[DEPRECATED] Prompt adapter has been '
+                            'removed. Setting this flag to True or False'
+                            ' has no effect on vLLM behavior.')
 
         return parser
 
@@ -1234,11 +1220,6 @@ class EngineArgs:
 
         load_config = self.create_load_config()
 
-        prompt_adapter_config = PromptAdapterConfig(
-            max_prompt_adapters=self.max_prompt_adapters,
-            max_prompt_adapter_token=self.max_prompt_adapter_token) \
-                                        if self.enable_prompt_adapter else None
-
         decoding_config = DecodingConfig(
             backend=self.guided_decoding_backend,
             disable_fallback=self.guided_decoding_disable_fallback,
@@ -1266,7 +1247,6 @@ class EngineArgs:
             load_config=load_config,
             decoding_config=decoding_config,
             observability_config=observability_config,
-            prompt_adapter_config=prompt_adapter_config,
             compilation_config=self.compilation_config,
             kv_transfer_config=self.kv_transfer_config,
             kv_events_config=self.kv_events_config,
@@ -1342,12 +1322,6 @@ class EngineArgs:
                                    recommend_to_remove=False)
                 return False
 
-        # No Prompt Adapter so far.
-        if self.enable_prompt_adapter:
-            _raise_or_fallback(feature_name="--enable-prompt-adapter",
-                               recommend_to_remove=False)
-            return False
-
         # No text embedding inputs so far.
         if self.enable_prompt_embeds:
             _raise_or_fallback(feature_name="--enable-prompt-embeds",
@@ -1469,7 +1443,6 @@ class EngineArgs:
 
                 if (is_gpu and not use_sliding_window and not use_spec_decode
                         and not self.enable_lora
-                        and not self.enable_prompt_adapter
                         and model_config.runner_type != "pooling"):
                     self.enable_chunked_prefill = True
                     logger.warning(