[Frontend][4/N] Improve all pooling task | Add plugin pooling task (#26973)

Signed-off-by: wang.yuqi <noooop@126.com>
Signed-off-by: Christian Pinto <christian.pinto@ibm.com>
Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>
Co-authored-by: Christian Pinto <christian.pinto@ibm.com>

vllm/plugins/io_processors/interface.py

@@ -9,6 +9,8 @@ from vllm.config import VllmConfig
 from vllm.entrypoints.openai.protocol import IOProcessorResponse
 from vllm.inputs.data import PromptType
 from vllm.outputs import PoolingRequestOutput
+from vllm.pooling_params import PoolingParams
+from vllm.sampling_params import SamplingParams
 
 IOProcessorInput = TypeVar("IOProcessorInput")
 IOProcessorOutput = TypeVar("IOProcessorOutput")
@@ -63,6 +65,11 @@ class IOProcessor(ABC, Generic[IOProcessorInput, IOProcessorOutput]):
     def parse_request(self, request: Any) -> IOProcessorInput:
         raise NotImplementedError
 
+    def validate_or_generate_params(
+        self, params: SamplingParams | PoolingParams | None = None
+    ) -> SamplingParams | PoolingParams:
+        return params or PoolingParams()
+
     @abstractmethod
     def output_to_response(
         self, plugin_output: IOProcessorOutput