Skip to content

vllm.v1.engine.processor

Processor

Source code in vllm/v1/engine/processor.py
class Processor:

    def __init__(
        self,
        vllm_config: VllmConfig,
        tokenizer: TokenizerGroup,
        mm_registry: MultiModalRegistry = MULTIMODAL_REGISTRY,
    ):

        self.vllm_config = vllm_config
        self.model_config = vllm_config.model_config
        self.cache_config = vllm_config.cache_config
        self.lora_config = vllm_config.lora_config
        self.decoding_config = vllm_config.decoding_config
        self.tokenizer = tokenizer

        self.generation_config_fields = (
            self.model_config.try_get_generation_config())
        self.input_preprocessor = InputPreprocessor(self.model_config,
                                                    self.tokenizer,
                                                    mm_registry)

        self.mm_input_cache_client = MirroredProcessingCache(self.model_config)

        # Multi-modal hasher (for images)
        self.use_hash = self.mm_input_cache_client.use_cache or \
            self.cache_config.enable_prefix_caching

    @property
    def mm_registry(self):
        return self.input_preprocessor.mm_registry

    def _validate_logprobs(
        self,
        params: SamplingParams,
    ) -> None:
        max_logprobs = self.model_config.max_logprobs
        # Validate sample logprobs.
        if params.logprobs and params.logprobs > max_logprobs:
            raise ValueError(
                f"Requested sample logprobs of {params.logprobs}, "
                f"which is greater than max allowed: {max_logprobs}")

        # Validate prompt logprobs.
        if params.prompt_logprobs and params.prompt_logprobs > max_logprobs:
            raise ValueError(
                f"Requested prompt logprobs of {params.prompt_logprobs}, "
                f"which is greater than max allowed: {max_logprobs}")

    def _validate_sampling_params(
        self,
        params: SamplingParams,
        lora_request: Optional[LoRARequest],
    ) -> None:
        self._validate_structured_output(params)
        self._validate_logit_bias(params)

        if params.allowed_token_ids is None:
            return
        if not params.allowed_token_ids:
            raise ValueError("allowed_token_ids is not None and empty!")
        tokenizer = self.tokenizer.get_lora_tokenizer(lora_request)
        vocab_size = len(tokenizer)
        if not all(0 <= tid < vocab_size for tid in params.allowed_token_ids):
            raise ValueError(
                "allowed_token_ids contains out-of-vocab token id!")

    def _validate_logit_bias(
        self,
        params: SamplingParams,
    ) -> None:
        """Validate logit_bias token IDs are within vocabulary range."""
        if not params.logit_bias:
            return

        vocab_size = self.model_config.get_vocab_size()
        invalid_token_ids = []

        for token_id in params.logit_bias:
            if token_id < 0 or token_id >= vocab_size:
                invalid_token_ids.append(token_id)

        if invalid_token_ids:
            raise ValueError(
                f"token_id(s) {invalid_token_ids} in logit_bias contain "
                f"out-of-vocab token ids. Vocabulary size: {vocab_size}")

    def _validate_supported_sampling_params(
        self,
        params: SamplingParams,
    ) -> None:
        # Best of not yet supported.
        if params.best_of is not None and params.best_of > 1:
            raise ValueError("vLLM V1 does not yet support best_of.")
        # Logits processors not supported.
        if params.logits_processors:
            raise ValueError("vLLM V1 does not support per request "
                             "user provided logits processors.")

    def _validate_params(
        self,
        params: Union[SamplingParams, PoolingParams],
        lora_request: Optional[LoRARequest],
    ):
        """
        Validate supported SamplingParam.
        Should raise ValueError if unsupported for API Server.
        """

        if isinstance(params, PoolingParams):
            return

        self._validate_logprobs(params)
        self._validate_sampling_params(params, lora_request)
        self._validate_supported_sampling_params(params)

    def _validate_lora(self, lora_request: Optional[LoRARequest]) -> None:
        if lora_request is not None and not self.lora_config:
            raise ValueError(f"Got lora_request {lora_request} but LoRA is "
                             "not enabled!")

    def _validate_structured_output(self, params: SamplingParams) -> None:
        if not params.guided_decoding or not self.decoding_config:
            return

        if self.model_config.skip_tokenizer_init and params.guided_decoding:
            raise ValueError(
                "Structured outputs requires a tokenizer so it can't be used with 'skip_tokenizer_init'"  # noqa: E501
            )

        engine_level_backend = self.decoding_config.backend
        if params.guided_decoding.backend:
            # Request-level backend selection is not supported in V1.
            # The values may differ if `params` is reused and was set
            # to a specific backend based on `auto` behavior in a previous
            # request. We remember that it was set as a result of `auto`
            # using the `_auto` option set on the backend in the params.
            if (params.guided_decoding.backend != engine_level_backend
                    and not (engine_level_backend == "auto"
                             and params.guided_decoding.backend_was_auto)):
                raise ValueError(
                    "Request-level structured output backend selection is no "
                    "longer supported. The request specified "
                    f"'{params.guided_decoding.backend}', but vLLM was "
                    f"initialised with '{engine_level_backend}'. This error "
                    "can be resolved by removing backend selection from the "
                    "request.")
        else:
            params.guided_decoding.backend = engine_level_backend

        # Request content validation
        if (isinstance(params.guided_decoding.choice, list)
                and not params.guided_decoding.choice):
            # It is invalid for choice to be an empty list
            raise ValueError(f"Choice '{params.guided_decoding.choice}' "
                             "cannot be an empty list")

        if engine_level_backend.startswith("xgrammar"):
            # xgrammar with no fallback
            validate_xgrammar_grammar(params)
        elif engine_level_backend.startswith("guidance"):
            # TODO: ideally we would have the LLTokenizer here as Lark syntax
            # allows <|special_token|> and similar, see
            # https://github.com/guidance-ai/llguidance/blob/main/docs/syntax.md#special-tokens
            # Without tokenizer these are disallowed in grammars.
            validate_guidance_grammar(params, tokenizer=None)
        else:
            # NOTE: engine_level_backend must be "auto" here, because we have
            # checked supported_backends above.
            # "auto" is an opt-in to opinionated behavior where we try to
            # choose a backend based on request contents. This is not the
            # default as it is less predictable and subject to change
            # between releases as feature support changes.
            try:
                validate_xgrammar_grammar(params)
                params.guided_decoding.backend = "xgrammar"
            except ValueError:
                # The request either failed validation
                # or includes some jsonschema feature(s) that
                # are not supported in xgrammar. Fall back to guidance.
                validate_guidance_grammar(params, tokenizer=None)
                params.guided_decoding.backend = "guidance"
            # Remember that this backend was set automatically
            params.guided_decoding.backend_was_auto = True

    def process_inputs(
        self,
        request_id: str,
        prompt: PromptType,
        params: Union[SamplingParams, PoolingParams],
        arrival_time: Optional[float] = None,
        lora_request: Optional[LoRARequest] = None,
        tokenization_kwargs: Optional[dict[str, Any]] = None,
        trace_headers: Optional[Mapping[str, str]] = None,
        prompt_adapter_request: Optional[PromptAdapterRequest] = None,
        priority: int = 0,
        data_parallel_rank: Optional[int] = None,
    ) -> tuple[Optional[str], EngineCoreRequest]:

        # TODO(woosuk): Support pooling models.
        # TODO(woosuk): Support encoder-decoder models.
        self._validate_lora(lora_request)
        self._validate_params(params, lora_request)
        if trace_headers is not None:
            raise ValueError("V1 does not support tracing yet.")
        if prompt_adapter_request is not None:
            raise ValueError("V1 does not support prompt_adapter_request.")

        data_parallel_size = self.vllm_config.parallel_config.data_parallel_size
        if data_parallel_rank is not None and not (0 <= data_parallel_rank <
                                                   data_parallel_size):
            raise ValueError(f"data_parallel_rank {data_parallel_rank} "
                             f"is out of range [0, {data_parallel_size}).")

        if arrival_time is None:
            arrival_time = time.time()

        # Process inputs, which includes:
        # 1. Tokenize text prompt, with LoRA request if one exists.
        # 2. For multimodal models with a merged preprocessor, preprocess
        #   multimodal data and expand prompt token ids accordingly.
        # 3. Apply prompt adapter to prompt token ids if one exists.
        processed_inputs: ProcessorInputs = self.input_preprocessor.preprocess(
            prompt,
            tokenization_kwargs=tokenization_kwargs,
            lora_request=lora_request,
            prompt_adapter_request=prompt_adapter_request,
            return_mm_hashes=self.use_hash,
        )
        from vllm.platforms import current_platform
        current_platform.validate_request(
            prompt=prompt,
            params=params,
            processed_inputs=processed_inputs,
        )
        eos_token_id = self.input_preprocessor.get_eos_token_id(lora_request)

        self._validate_model_inputs(processed_inputs, lora_request)

        encoder_inputs, decoder_inputs = split_enc_dec_inputs(processed_inputs)

        # TODO: Impl encoder-decoder
        if encoder_inputs is not None:
            raise NotImplementedError

        sampling_params = None
        pooling_params = None
        if isinstance(params, SamplingParams):
            # TODO: can we avoid cloning here in multiproc case?
            sampling_params = params.clone()
            # If unset max tokens, then generate up to the max_model_len.
            if sampling_params.max_tokens is None:
                sampling_params.max_tokens = (
                    self.model_config.max_model_len -
                    len(decoder_inputs["prompt_token_ids"]))
            sampling_params.update_from_generation_config(
                self.generation_config_fields, eos_token_id)
            sampling_params.update_from_tokenizer(
                self.tokenizer.get_lora_tokenizer(lora_request))
        else:
            pooling_params = params.clone()

        # Multimodal related.
        sorted_mm_inputs: Optional[Sequence[Optional[MultiModalKwargs]]] = None
        sorted_mm_positions: Optional[list[PlaceholderRange]] = None
        sorted_mm_hashes: Optional[list[str]] = None
        if decoder_inputs["type"] == "multimodal":
            decoder_mm_inputs = decoder_inputs["mm_kwargs"]

            # Merge and flatten multimodal placeholders, hashes and inputs
            # from dictionaries to lists, and sort them by each item's position
            # in the input sequence.
            (
                sorted_item_modalities,
                sorted_mm_positions,
                sorted_mm_hashes,
            ) = merge_and_sort_multimodal_metadata(
                decoder_inputs["mm_placeholders"],
                decoder_inputs["mm_hashes"] if self.use_hash else None,
            )

            # The output of merged multi-modal processor (`decoder_mm_inputs`)
            # is a single MultiModalKwargs for all items from all modalities.
            # This code flattens kwargs for individual items in a list and
            # sorts them by each item's position in the input sequence if there
            # are multiple modalities.
            unique_modalities = set(sorted_item_modalities)
            if len(unique_modalities) > 1:
                orig_sorted_mm_inputs = []
                used_indices = {modality: 0 for modality in unique_modalities}

                for modality in sorted_item_modalities:
                    items = decoder_mm_inputs.get_items(modality)
                    item = items[used_indices[modality]]

                    orig_sorted_mm_inputs.append(
                        MultiModalKwargs.from_items([item]))
                    used_indices[modality] += 1
            else:
                orig_sorted_mm_inputs = [
                    MultiModalKwargs.from_items([item]) for item in
                    decoder_mm_inputs.get_items(sorted_item_modalities[0])
                ]

            if sorted_mm_hashes is not None:
                sorted_mm_inputs = self.mm_input_cache_client.get_and_update_p0(
                    orig_sorted_mm_inputs, sorted_mm_hashes)
            else:
                sorted_mm_inputs = orig_sorted_mm_inputs

        return decoder_inputs.get("prompt"), EngineCoreRequest(
            request_id=request_id,
            prompt_token_ids=decoder_inputs["prompt_token_ids"],
            mm_inputs=sorted_mm_inputs,
            mm_hashes=sorted_mm_hashes,
            mm_placeholders=sorted_mm_positions,
            sampling_params=sampling_params,
            pooling_params=pooling_params,
            eos_token_id=eos_token_id,
            arrival_time=arrival_time,
            lora_request=lora_request,
            cache_salt=decoder_inputs.get("cache_salt"),
            priority=priority,
            data_parallel_rank=data_parallel_rank,
        )

    def _validate_model_inputs(self,
                               inputs: ProcessorInputs,
                               lora_request: Optional[LoRARequest] = None):
        encoder_inputs, decoder_inputs = split_enc_dec_inputs(inputs)

        if encoder_inputs is not None:
            self._validate_model_input(encoder_inputs,
                                       lora_request,
                                       prompt_type="encoder")

        self._validate_model_input(decoder_inputs,
                                   lora_request,
                                   prompt_type="decoder")

    def _validate_model_input(
        self,
        prompt_inputs: SingletonInputs,
        lora_request: Optional[LoRARequest],
        *,
        prompt_type: Literal["encoder", "decoder"],
    ):
        model_config = self.model_config
        tokenizer = self.tokenizer.get_lora_tokenizer(lora_request)

        prompt_ids = prompt_inputs["prompt_token_ids"]
        if not prompt_ids:
            if prompt_type == "encoder" and model_config.is_multimodal_model:
                pass  # Mllama may have empty encoder inputs for text-only data
            else:
                raise ValueError(f"The {prompt_type} prompt cannot be empty")

        max_input_id = max(prompt_ids, default=0)
        if max_input_id > tokenizer.max_token_id:
            raise ValueError(f"Token id {max_input_id} is out of vocabulary")

        max_prompt_len = self.model_config.max_model_len
        if len(prompt_ids) > max_prompt_len:
            if prompt_type == "encoder" and model_config.is_multimodal_model:
                mm_registry = self.input_preprocessor.mm_registry
                mm_processor = mm_registry.create_processor(
                    model_config,
                    tokenizer=tokenizer,
                )
                assert isinstance(mm_processor, EncDecMultiModalProcessor)

                if mm_processor.pad_dummy_encoder_prompt:
                    return  # Skip encoder length check for Whisper

            if model_config.is_multimodal_model:
                suggestion = (
                    "Make sure that `max_model_len` is no smaller than the "
                    "number of text tokens plus multimodal tokens. For image "
                    "inputs, the number of image tokens depends on the number "
                    "of images, and possibly their aspect ratios as well.")
            else:
                suggestion = (
                    "Make sure that `max_model_len` is no smaller than the "
                    "number of text tokens.")

            raise ValueError(
                f"The {prompt_type} prompt (length {len(prompt_ids)}) is "
                f"longer than the maximum model length of {max_prompt_len}. "
                f"{suggestion}")

cache_config instance-attribute

cache_config = cache_config

decoding_config instance-attribute

decoding_config = decoding_config

generation_config_fields instance-attribute

generation_config_fields = try_get_generation_config()

input_preprocessor instance-attribute

input_preprocessor = InputPreprocessor(
    model_config, tokenizer, mm_registry
)

lora_config instance-attribute

lora_config = lora_config

mm_input_cache_client instance-attribute

mm_input_cache_client = MirroredProcessingCache(
    model_config
)

mm_registry property

mm_registry

model_config instance-attribute

model_config = model_config

tokenizer instance-attribute

tokenizer = tokenizer

use_hash instance-attribute

use_hash = use_cache or enable_prefix_caching

vllm_config instance-attribute

vllm_config = vllm_config

__init__

__init__(
    vllm_config: VllmConfig,
    tokenizer: TokenizerGroup,
    mm_registry: MultiModalRegistry = MULTIMODAL_REGISTRY,
)
Source code in vllm/v1/engine/processor.py
def __init__(
    self,
    vllm_config: VllmConfig,
    tokenizer: TokenizerGroup,
    mm_registry: MultiModalRegistry = MULTIMODAL_REGISTRY,
):

    self.vllm_config = vllm_config
    self.model_config = vllm_config.model_config
    self.cache_config = vllm_config.cache_config
    self.lora_config = vllm_config.lora_config
    self.decoding_config = vllm_config.decoding_config
    self.tokenizer = tokenizer

    self.generation_config_fields = (
        self.model_config.try_get_generation_config())
    self.input_preprocessor = InputPreprocessor(self.model_config,
                                                self.tokenizer,
                                                mm_registry)

    self.mm_input_cache_client = MirroredProcessingCache(self.model_config)

    # Multi-modal hasher (for images)
    self.use_hash = self.mm_input_cache_client.use_cache or \
        self.cache_config.enable_prefix_caching

_validate_logit_bias

_validate_logit_bias(params: SamplingParams) -> None

Validate logit_bias token IDs are within vocabulary range.

Source code in vllm/v1/engine/processor.py
def _validate_logit_bias(
    self,
    params: SamplingParams,
) -> None:
    """Validate logit_bias token IDs are within vocabulary range."""
    if not params.logit_bias:
        return

    vocab_size = self.model_config.get_vocab_size()
    invalid_token_ids = []

    for token_id in params.logit_bias:
        if token_id < 0 or token_id >= vocab_size:
            invalid_token_ids.append(token_id)

    if invalid_token_ids:
        raise ValueError(
            f"token_id(s) {invalid_token_ids} in logit_bias contain "
            f"out-of-vocab token ids. Vocabulary size: {vocab_size}")

_validate_logprobs

_validate_logprobs(params: SamplingParams) -> None
Source code in vllm/v1/engine/processor.py
def _validate_logprobs(
    self,
    params: SamplingParams,
) -> None:
    max_logprobs = self.model_config.max_logprobs
    # Validate sample logprobs.
    if params.logprobs and params.logprobs > max_logprobs:
        raise ValueError(
            f"Requested sample logprobs of {params.logprobs}, "
            f"which is greater than max allowed: {max_logprobs}")

    # Validate prompt logprobs.
    if params.prompt_logprobs and params.prompt_logprobs > max_logprobs:
        raise ValueError(
            f"Requested prompt logprobs of {params.prompt_logprobs}, "
            f"which is greater than max allowed: {max_logprobs}")

_validate_lora

_validate_lora(lora_request: Optional[LoRARequest]) -> None
Source code in vllm/v1/engine/processor.py
def _validate_lora(self, lora_request: Optional[LoRARequest]) -> None:
    if lora_request is not None and not self.lora_config:
        raise ValueError(f"Got lora_request {lora_request} but LoRA is "
                         "not enabled!")

_validate_model_input

_validate_model_input(
    prompt_inputs: SingletonInputs,
    lora_request: Optional[LoRARequest],
    *,
    prompt_type: Literal["encoder", "decoder"],
)
Source code in vllm/v1/engine/processor.py
def _validate_model_input(
    self,
    prompt_inputs: SingletonInputs,
    lora_request: Optional[LoRARequest],
    *,
    prompt_type: Literal["encoder", "decoder"],
):
    model_config = self.model_config
    tokenizer = self.tokenizer.get_lora_tokenizer(lora_request)

    prompt_ids = prompt_inputs["prompt_token_ids"]
    if not prompt_ids:
        if prompt_type == "encoder" and model_config.is_multimodal_model:
            pass  # Mllama may have empty encoder inputs for text-only data
        else:
            raise ValueError(f"The {prompt_type} prompt cannot be empty")

    max_input_id = max(prompt_ids, default=0)
    if max_input_id > tokenizer.max_token_id:
        raise ValueError(f"Token id {max_input_id} is out of vocabulary")

    max_prompt_len = self.model_config.max_model_len
    if len(prompt_ids) > max_prompt_len:
        if prompt_type == "encoder" and model_config.is_multimodal_model:
            mm_registry = self.input_preprocessor.mm_registry
            mm_processor = mm_registry.create_processor(
                model_config,
                tokenizer=tokenizer,
            )
            assert isinstance(mm_processor, EncDecMultiModalProcessor)

            if mm_processor.pad_dummy_encoder_prompt:
                return  # Skip encoder length check for Whisper

        if model_config.is_multimodal_model:
            suggestion = (
                "Make sure that `max_model_len` is no smaller than the "
                "number of text tokens plus multimodal tokens. For image "
                "inputs, the number of image tokens depends on the number "
                "of images, and possibly their aspect ratios as well.")
        else:
            suggestion = (
                "Make sure that `max_model_len` is no smaller than the "
                "number of text tokens.")

        raise ValueError(
            f"The {prompt_type} prompt (length {len(prompt_ids)}) is "
            f"longer than the maximum model length of {max_prompt_len}. "
            f"{suggestion}")

_validate_model_inputs

_validate_model_inputs(
    inputs: ProcessorInputs,
    lora_request: Optional[LoRARequest] = None,
)
Source code in vllm/v1/engine/processor.py
def _validate_model_inputs(self,
                           inputs: ProcessorInputs,
                           lora_request: Optional[LoRARequest] = None):
    encoder_inputs, decoder_inputs = split_enc_dec_inputs(inputs)

    if encoder_inputs is not None:
        self._validate_model_input(encoder_inputs,
                                   lora_request,
                                   prompt_type="encoder")

    self._validate_model_input(decoder_inputs,
                               lora_request,
                               prompt_type="decoder")

_validate_params

_validate_params(
    params: Union[SamplingParams, PoolingParams],
    lora_request: Optional[LoRARequest],
)

Validate supported SamplingParam. Should raise ValueError if unsupported for API Server.

Source code in vllm/v1/engine/processor.py
def _validate_params(
    self,
    params: Union[SamplingParams, PoolingParams],
    lora_request: Optional[LoRARequest],
):
    """
    Validate supported SamplingParam.
    Should raise ValueError if unsupported for API Server.
    """

    if isinstance(params, PoolingParams):
        return

    self._validate_logprobs(params)
    self._validate_sampling_params(params, lora_request)
    self._validate_supported_sampling_params(params)

_validate_sampling_params

_validate_sampling_params(
    params: SamplingParams,
    lora_request: Optional[LoRARequest],
) -> None
Source code in vllm/v1/engine/processor.py
def _validate_sampling_params(
    self,
    params: SamplingParams,
    lora_request: Optional[LoRARequest],
) -> None:
    self._validate_structured_output(params)
    self._validate_logit_bias(params)

    if params.allowed_token_ids is None:
        return
    if not params.allowed_token_ids:
        raise ValueError("allowed_token_ids is not None and empty!")
    tokenizer = self.tokenizer.get_lora_tokenizer(lora_request)
    vocab_size = len(tokenizer)
    if not all(0 <= tid < vocab_size for tid in params.allowed_token_ids):
        raise ValueError(
            "allowed_token_ids contains out-of-vocab token id!")

_validate_structured_output

_validate_structured_output(params: SamplingParams) -> None
Source code in vllm/v1/engine/processor.py
def _validate_structured_output(self, params: SamplingParams) -> None:
    if not params.guided_decoding or not self.decoding_config:
        return

    if self.model_config.skip_tokenizer_init and params.guided_decoding:
        raise ValueError(
            "Structured outputs requires a tokenizer so it can't be used with 'skip_tokenizer_init'"  # noqa: E501
        )

    engine_level_backend = self.decoding_config.backend
    if params.guided_decoding.backend:
        # Request-level backend selection is not supported in V1.
        # The values may differ if `params` is reused and was set
        # to a specific backend based on `auto` behavior in a previous
        # request. We remember that it was set as a result of `auto`
        # using the `_auto` option set on the backend in the params.
        if (params.guided_decoding.backend != engine_level_backend
                and not (engine_level_backend == "auto"
                         and params.guided_decoding.backend_was_auto)):
            raise ValueError(
                "Request-level structured output backend selection is no "
                "longer supported. The request specified "
                f"'{params.guided_decoding.backend}', but vLLM was "
                f"initialised with '{engine_level_backend}'. This error "
                "can be resolved by removing backend selection from the "
                "request.")
    else:
        params.guided_decoding.backend = engine_level_backend

    # Request content validation
    if (isinstance(params.guided_decoding.choice, list)
            and not params.guided_decoding.choice):
        # It is invalid for choice to be an empty list
        raise ValueError(f"Choice '{params.guided_decoding.choice}' "
                         "cannot be an empty list")

    if engine_level_backend.startswith("xgrammar"):
        # xgrammar with no fallback
        validate_xgrammar_grammar(params)
    elif engine_level_backend.startswith("guidance"):
        # TODO: ideally we would have the LLTokenizer here as Lark syntax
        # allows <|special_token|> and similar, see
        # https://github.com/guidance-ai/llguidance/blob/main/docs/syntax.md#special-tokens
        # Without tokenizer these are disallowed in grammars.
        validate_guidance_grammar(params, tokenizer=None)
    else:
        # NOTE: engine_level_backend must be "auto" here, because we have
        # checked supported_backends above.
        # "auto" is an opt-in to opinionated behavior where we try to
        # choose a backend based on request contents. This is not the
        # default as it is less predictable and subject to change
        # between releases as feature support changes.
        try:
            validate_xgrammar_grammar(params)
            params.guided_decoding.backend = "xgrammar"
        except ValueError:
            # The request either failed validation
            # or includes some jsonschema feature(s) that
            # are not supported in xgrammar. Fall back to guidance.
            validate_guidance_grammar(params, tokenizer=None)
            params.guided_decoding.backend = "guidance"
        # Remember that this backend was set automatically
        params.guided_decoding.backend_was_auto = True

_validate_supported_sampling_params

_validate_supported_sampling_params(
    params: SamplingParams,
) -> None
Source code in vllm/v1/engine/processor.py
def _validate_supported_sampling_params(
    self,
    params: SamplingParams,
) -> None:
    # Best of not yet supported.
    if params.best_of is not None and params.best_of > 1:
        raise ValueError("vLLM V1 does not yet support best_of.")
    # Logits processors not supported.
    if params.logits_processors:
        raise ValueError("vLLM V1 does not support per request "
                         "user provided logits processors.")

process_inputs

process_inputs(
    request_id: str,
    prompt: PromptType,
    params: Union[SamplingParams, PoolingParams],
    arrival_time: Optional[float] = None,
    lora_request: Optional[LoRARequest] = None,
    tokenization_kwargs: Optional[dict[str, Any]] = None,
    trace_headers: Optional[Mapping[str, str]] = None,
    prompt_adapter_request: Optional[
        PromptAdapterRequest
    ] = None,
    priority: int = 0,
    data_parallel_rank: Optional[int] = None,
) -> tuple[Optional[str], EngineCoreRequest]
Source code in vllm/v1/engine/processor.py
def process_inputs(
    self,
    request_id: str,
    prompt: PromptType,
    params: Union[SamplingParams, PoolingParams],
    arrival_time: Optional[float] = None,
    lora_request: Optional[LoRARequest] = None,
    tokenization_kwargs: Optional[dict[str, Any]] = None,
    trace_headers: Optional[Mapping[str, str]] = None,
    prompt_adapter_request: Optional[PromptAdapterRequest] = None,
    priority: int = 0,
    data_parallel_rank: Optional[int] = None,
) -> tuple[Optional[str], EngineCoreRequest]:

    # TODO(woosuk): Support pooling models.
    # TODO(woosuk): Support encoder-decoder models.
    self._validate_lora(lora_request)
    self._validate_params(params, lora_request)
    if trace_headers is not None:
        raise ValueError("V1 does not support tracing yet.")
    if prompt_adapter_request is not None:
        raise ValueError("V1 does not support prompt_adapter_request.")

    data_parallel_size = self.vllm_config.parallel_config.data_parallel_size
    if data_parallel_rank is not None and not (0 <= data_parallel_rank <
                                               data_parallel_size):
        raise ValueError(f"data_parallel_rank {data_parallel_rank} "
                         f"is out of range [0, {data_parallel_size}).")

    if arrival_time is None:
        arrival_time = time.time()

    # Process inputs, which includes:
    # 1. Tokenize text prompt, with LoRA request if one exists.
    # 2. For multimodal models with a merged preprocessor, preprocess
    #   multimodal data and expand prompt token ids accordingly.
    # 3. Apply prompt adapter to prompt token ids if one exists.
    processed_inputs: ProcessorInputs = self.input_preprocessor.preprocess(
        prompt,
        tokenization_kwargs=tokenization_kwargs,
        lora_request=lora_request,
        prompt_adapter_request=prompt_adapter_request,
        return_mm_hashes=self.use_hash,
    )
    from vllm.platforms import current_platform
    current_platform.validate_request(
        prompt=prompt,
        params=params,
        processed_inputs=processed_inputs,
    )
    eos_token_id = self.input_preprocessor.get_eos_token_id(lora_request)

    self._validate_model_inputs(processed_inputs, lora_request)

    encoder_inputs, decoder_inputs = split_enc_dec_inputs(processed_inputs)

    # TODO: Impl encoder-decoder
    if encoder_inputs is not None:
        raise NotImplementedError

    sampling_params = None
    pooling_params = None
    if isinstance(params, SamplingParams):
        # TODO: can we avoid cloning here in multiproc case?
        sampling_params = params.clone()
        # If unset max tokens, then generate up to the max_model_len.
        if sampling_params.max_tokens is None:
            sampling_params.max_tokens = (
                self.model_config.max_model_len -
                len(decoder_inputs["prompt_token_ids"]))
        sampling_params.update_from_generation_config(
            self.generation_config_fields, eos_token_id)
        sampling_params.update_from_tokenizer(
            self.tokenizer.get_lora_tokenizer(lora_request))
    else:
        pooling_params = params.clone()

    # Multimodal related.
    sorted_mm_inputs: Optional[Sequence[Optional[MultiModalKwargs]]] = None
    sorted_mm_positions: Optional[list[PlaceholderRange]] = None
    sorted_mm_hashes: Optional[list[str]] = None
    if decoder_inputs["type"] == "multimodal":
        decoder_mm_inputs = decoder_inputs["mm_kwargs"]

        # Merge and flatten multimodal placeholders, hashes and inputs
        # from dictionaries to lists, and sort them by each item's position
        # in the input sequence.
        (
            sorted_item_modalities,
            sorted_mm_positions,
            sorted_mm_hashes,
        ) = merge_and_sort_multimodal_metadata(
            decoder_inputs["mm_placeholders"],
            decoder_inputs["mm_hashes"] if self.use_hash else None,
        )

        # The output of merged multi-modal processor (`decoder_mm_inputs`)
        # is a single MultiModalKwargs for all items from all modalities.
        # This code flattens kwargs for individual items in a list and
        # sorts them by each item's position in the input sequence if there
        # are multiple modalities.
        unique_modalities = set(sorted_item_modalities)
        if len(unique_modalities) > 1:
            orig_sorted_mm_inputs = []
            used_indices = {modality: 0 for modality in unique_modalities}

            for modality in sorted_item_modalities:
                items = decoder_mm_inputs.get_items(modality)
                item = items[used_indices[modality]]

                orig_sorted_mm_inputs.append(
                    MultiModalKwargs.from_items([item]))
                used_indices[modality] += 1
        else:
            orig_sorted_mm_inputs = [
                MultiModalKwargs.from_items([item]) for item in
                decoder_mm_inputs.get_items(sorted_item_modalities[0])
            ]

        if sorted_mm_hashes is not None:
            sorted_mm_inputs = self.mm_input_cache_client.get_and_update_p0(
                orig_sorted_mm_inputs, sorted_mm_hashes)
        else:
            sorted_mm_inputs = orig_sorted_mm_inputs

    return decoder_inputs.get("prompt"), EngineCoreRequest(
        request_id=request_id,
        prompt_token_ids=decoder_inputs["prompt_token_ids"],
        mm_inputs=sorted_mm_inputs,
        mm_hashes=sorted_mm_hashes,
        mm_placeholders=sorted_mm_positions,
        sampling_params=sampling_params,
        pooling_params=pooling_params,
        eos_token_id=eos_token_id,
        arrival_time=arrival_time,
        lora_request=lora_request,
        cache_salt=decoder_inputs.get("cache_salt"),
        priority=priority,
        data_parallel_rank=data_parallel_rank,
    )