inference.py

import abc
import os
from typing import Any, Dict, List, Literal, Optional, Union

from tqdm import tqdm

from .artifact import Artifact
from .deprecation_utils import deprecation
from .logging_utils import get_logger
from .operator import PackageRequirementsMixin


class InferenceEngine(abc.ABC, Artifact):
    """Abstract base class for inference."""

    @abc.abstractmethod
    def _infer(self, dataset):
        """Perform inference on the input dataset."""
        pass

    def infer(self, dataset) -> str:
        """Verifies instances of a dataset and performs inference."""
        [self.verify_instance(instance) for instance in dataset]
        return self._infer(dataset)

    @deprecation(version="2.0.0")
    def _set_inference_parameters(self):
        """Sets inference parameters of an instance based on 'parameters' attribute (if given)."""
        if hasattr(self, "parameters") and self.parameters is not None:
            get_logger().warning(
                f"The 'parameters' attribute of '{self.get_pretty_print_name()}' "
                f"is deprecated. Please pass inference parameters directly to the "
                f"inference engine instance instead."
            )

            for param, param_dict_val in self.parameters.to_dict(
                [self.parameters]
            ).items():
                param_inst_val = getattr(self, param)
                if param_inst_val is None:
                    setattr(self, param, param_dict_val)


class LogProbInferenceEngine(abc.ABC, Artifact):
    """Abstract base class for inference with log probs."""

    @abc.abstractmethod
    def _infer_log_probs(self, dataset):
        """Perform inference on the input dataset that returns log probs."""
        pass

    def infer_log_probs(self, dataset) -> List[Dict]:
        """Verifies instances of a dataset and performs inference that returns log probabilities of top tokens.

        For each instance , returns a list of top tokens per position.
        [ "top_tokens": [ { "text": ..., "logprob": ...} , ... ]

        """
        [self.verify_instance(instance) for instance in dataset]
        return self._infer_log_probs(dataset)


class HFPipelineBasedInferenceEngine(InferenceEngine, PackageRequirementsMixin):
    model_name: str
    max_new_tokens: int
    use_fp16: bool = True
    lazy_load: bool = False

    _requirements_list = {
        "transformers": "Install huggingface package using 'pip install --upgrade transformers"
    }

    def _prepare_pipeline(self):
        import torch
        from transformers import AutoConfig, pipeline

        model_args: Dict[str, Any] = (
            {"torch_dtype": torch.float16} if self.use_fp16 else {}
        )
        model_args.update({"max_new_tokens": self.max_new_tokens})

        device = torch.device(
            "mps"
            if torch.backends.mps.is_available()
            else 0
            if torch.cuda.is_available()
            else "cpu"
        )
        # We do this, because in some cases, using device:auto will offload some weights to the cpu
        # (even though the model might *just* fit to a single gpu), even if there is a gpu available, and this will
        # cause an error because the data is always on the gpu
        if torch.cuda.device_count() > 1:
            assert device == torch.device(0)
            model_args.update({"device_map": "auto"})
        else:
            model_args.update({"device": device})

        task = (
            "text2text-generation"
            if AutoConfig.from_pretrained(
                self.model_name, trust_remote_code=True
            ).is_encoder_decoder
            else "text-generation"
        )

        if task == "text-generation":
            model_args.update({"return_full_text": False})

        self.model = pipeline(
            model=self.model_name, trust_remote_code=True, **model_args
        )

    def prepare(self):
        if not self.lazy_load:
            self._prepare_pipeline()

    def is_pipeline_initialized(self):
        return hasattr(self, "model") and self.model is not None

    def _infer(self, dataset):
        if not self.is_pipeline_initialized():
            self._prepare_pipeline()

        outputs = []
        for output in self.model([instance["source"] for instance in dataset]):
            if isinstance(output, list):
                output = output[0]
            outputs.append(output["generated_text"])
        return outputs


class MockInferenceEngine(InferenceEngine):
    model_name: str

    def prepare(self):
        return

    def _infer(self, dataset):
        return ["[[10]]" for instance in dataset]


class IbmGenAiInferenceEngineParamsMixin(Artifact):
    beam_width: Optional[int] = None
    decoding_method: Optional[Literal["greedy", "sample"]] = None
    include_stop_sequence: Optional[bool] = None
    length_penalty: Any = None
    max_new_tokens: Optional[int] = None
    min_new_tokens: Optional[int] = None
    random_seed: Optional[int] = None
    repetition_penalty: Optional[float] = None
    return_options: Any = None
    stop_sequences: Optional[List[str]] = None
    temperature: Optional[float] = None
    time_limit: Optional[int] = None
    top_k: Optional[int] = None
    top_p: Optional[float] = None
    truncate_input_tokens: Optional[int] = None
    typical_p: Optional[float] = None


@deprecation(version="2.0.0", alternative=IbmGenAiInferenceEngineParamsMixin)
class IbmGenAiInferenceEngineParams(Artifact):
    beam_width: Optional[int] = None
    decoding_method: Optional[Literal["greedy", "sample"]] = None
    include_stop_sequence: Optional[bool] = None
    length_penalty: Any = None
    max_new_tokens: Optional[int] = None
    min_new_tokens: Optional[int] = None
    random_seed: Optional[int] = None
    repetition_penalty: Optional[float] = None
    return_options: Any = None
    stop_sequences: Optional[List[str]] = None
    temperature: Optional[float] = None
    time_limit: Optional[int] = None
    top_k: Optional[int] = None
    top_p: Optional[float] = None
    truncate_input_tokens: Optional[int] = None
    typical_p: Optional[float] = None


class IbmGenAiInferenceEngine(
    InferenceEngine, IbmGenAiInferenceEngineParamsMixin, PackageRequirementsMixin
):
    label: str = "ibm_genai"
    model_name: str
    _requirements_list = {
        "genai": "Install ibm-genai package using 'pip install --upgrade ibm-generative-ai"
    }
    data_classification_policy = ["public", "proprietary"]
    parameters: Optional[IbmGenAiInferenceEngineParams] = None

    def prepare(self):
        from genai import Client, Credentials

        api_key_env_var_name = "GENAI_KEY"
        api_key = os.environ.get(api_key_env_var_name)
        assert api_key is not None, (
            f"Error while trying to run IbmGenAiInferenceEngine."
            f" Please set the environment param '{api_key_env_var_name}'."
        )
        credentials = Credentials(api_key=api_key)
        self.client = Client(credentials=credentials)

        self._set_inference_parameters()

    def _infer(self, dataset):
        from genai.schema import TextGenerationParameters

        genai_params = TextGenerationParameters(
            **self.to_dict([IbmGenAiInferenceEngineParamsMixin])
        )

        return [
            response.results[0].generated_text
            for response in self.client.text.generation.create(
                model_id=self.model_name,
                inputs=[instance["source"] for instance in dataset],
                parameters=genai_params,
            )
        ]


class OpenAiInferenceEngineParamsMixin(Artifact):
    frequency_penalty: Optional[float] = None
    presence_penalty: Optional[float] = None
    max_tokens: Optional[int] = None
    seed: Optional[int] = None
    stop: Union[Optional[str], List[str]] = None
    temperature: Optional[float] = None
    top_p: Optional[float] = None
    top_logprobs: Optional[int] = 20
    logit_bias: Optional[Dict[str, int]] = None
    logprobs: Optional[bool] = None
    n: Optional[int] = None
    parallel_tool_calls: bool = None
    service_tier: Optional[Literal["auto", "default"]] = None


@deprecation(version="2.0.0", alternative=OpenAiInferenceEngineParamsMixin)
class OpenAiInferenceEngineParams(Artifact):
    frequency_penalty: Optional[float] = None
    presence_penalty: Optional[float] = None
    max_tokens: Optional[int] = None
    seed: Optional[int] = None
    stop: Union[Optional[str], List[str]] = None
    temperature: Optional[float] = None
    top_p: Optional[float] = None
    top_logprobs: Optional[int] = 20
    logit_bias: Optional[Dict[str, int]] = None
    logprobs: Optional[bool] = None
    n: Optional[int] = None
    parallel_tool_calls: bool = None
    service_tier: Optional[Literal["auto", "default"]] = None


class OpenAiInferenceEngine(
    InferenceEngine,
    LogProbInferenceEngine,
    OpenAiInferenceEngineParamsMixin,
    PackageRequirementsMixin,
):
    label: str = "openai"
    model_name: str
    _requirements_list = {
        "openai": "Install openai package using 'pip install --upgrade openai"
    }
    data_classification_policy = ["public"]
    parameters: Optional[OpenAiInferenceEngineParams] = None

    def prepare(self):
        from openai import OpenAI

        api_key_env_var_name = "OPENAI_API_KEY"
        api_key = os.environ.get(api_key_env_var_name)
        assert api_key is not None, (
            f"Error while trying to run OpenAiInferenceEngine."
            f" Please set the environment param '{api_key_env_var_name}'."
        )

        self.client = OpenAI(api_key=api_key)

        self._set_inference_parameters()

    def _infer(self, dataset):
        outputs = []
        for instance in tqdm(dataset, desc="Inferring with openAI API"):
            response = self.client.chat.completions.create(
                messages=[
                    # {
                    #     "role": "system",
                    #     "content": self.system_prompt,
                    # },
                    {
                        "role": "user",
                        "content": instance["source"],
                    }
                ],
                model=self.model_name,
                **self.to_dict([OpenAiInferenceEngineParamsMixin]),
            )
            output = response.choices[0].message.content

            outputs.append(output)

        return outputs

    def _infer_log_probs(self, dataset):
        outputs = []
        for instance in tqdm(dataset, desc="Inferring with openAI API"):
            response = self.client.chat.completions.create(
                messages=[
                    # {
                    #     "role": "system",
                    #     "content": self.system_prompt,
                    # },
                    {
                        "role": "user",
                        "content": instance["source"],
                    }
                ],
                model=self.model_name,
                **self.to_dict([OpenAiInferenceEngineParamsMixin]),
            )
            top_logprobs_response = response.choices[0].logprobs.content
            output = [
                {
                    "top_tokens": [
                        {"text": obj.token, "logprob": obj.logprob}
                        for obj in generated_token.top_logprobs
                    ]
                }
                for generated_token in top_logprobs_response
            ]
            outputs.append(output)
        return outputs


class WMLInferenceEngineParamsMixin(Artifact):
    decoding_method: Optional[Literal["greedy", "sample"]] = None
    length_penalty: Optional[Dict[str, Union[int, float]]] = None
    temperature: Optional[float] = None
    top_p: Optional[float] = None
    top_k: Optional[int] = None
    random_seed: Optional[int] = None
    repetition_penalty: Optional[float] = None
    min_new_tokens: Optional[int] = None
    max_new_tokens: Optional[int] = None
    stop_sequences: Optional[List[str]] = None
    time_limit: Optional[int] = None
    truncate_input_tokens: Optional[int] = None
    prompt_variables: Optional[Dict[str, Any]] = None
    return_options: Optional[Dict[str, bool]] = None


@deprecation(version="2.0.0", alternative=WMLInferenceEngineParamsMixin)
class WMLInferenceEngineParams(Artifact):
    decoding_method: Optional[Literal["greedy", "sample"]] = None
    length_penalty: Optional[Dict[str, Union[int, float]]] = None
    temperature: Optional[float] = None
    top_p: Optional[float] = None
    top_k: Optional[int] = None
    random_seed: Optional[int] = None
    repetition_penalty: Optional[float] = None
    min_new_tokens: Optional[int] = None
    max_new_tokens: Optional[int] = None
    stop_sequences: Optional[List[str]] = None
    time_limit: Optional[int] = None
    truncate_input_tokens: Optional[int] = None
    prompt_variables: Optional[Dict[str, Any]] = None
    return_options: Optional[Dict[str, bool]] = None


class WMLInferenceEngine(
    InferenceEngine, WMLInferenceEngineParamsMixin, PackageRequirementsMixin
):
    """Runs inference using ibm-watsonx-ai.

    Attributes:
        client: By default, it is created by a class instance but can be directly
            provided instead as an instance of 'ibm_watsonx_ai.client.APIClient'.
        credentials: By default, it is created by a class instance which tries to retrieve
            proper environment variables ("WML_URL", "WML_PROJECT_ID", "WML_APIKEY").
            However, either a dictionary with the following keys: "url", "apikey",
            "project_id", or an instance of 'ibm_watsonx_ai.credentials.Credentials'
            can be directly provided instead.
        model_name (str, optional): ID of a model to be used for inference. Mutually
            exclusive with 'deployment_id'.
        deployment_id (str, optional): Deployment ID of a tuned model to be used for
            inference. Mutually exclusive with 'model_name'.
        parameters (WMLInferenceEngineParams, optional): Instance of WMLInferenceEngineParams
            which defines inference parameters and their values. Deprecated attribute, please
            pass respective parameters directly to the WMLInferenceEngine class instead.

    Examples:
        from .api import load_dataset

        wml_credentials = {
            "url": "some_url", "project_id": "some_id", "api_key": "some_key"
        }
        model_name = "google/flan-t5-xxl"
        wml_inference = WMLInferenceEngine(
            credentials=wml_credentials,
            model_name=model_name,
            data_classification_policy=["public"],
            top_p=0.5,
            random_seed=123,
        )

        dataset = load_dataset(
            dataset_query="card=cards.argument_topic,template_card_index=0,loader_limit=5"
        )
        results = wml_inference.infer(dataset["test"])
    """

    client: Any = None
    credentials: Any = None
    model_name: Optional[str] = None
    deployment_id: Optional[str] = None
    label: str = "wml"
    _requirements_list = {
        "ibm_watsonx_ai": "Install ibm-watsonx-ai package using 'pip install --upgrade ibm-watsonx-ai'. "
        "It is advised to have Python version >=3.10 installed, as at lower version this package "
        "may cause conflicts with other installed packages."
    }
    data_classification_policy = ["proprietary"]
    parameters: Optional[WMLInferenceEngineParams] = None

    @staticmethod
    def _read_wml_credentials_from_env() -> Dict[str, str]:
        credentials = {}
        for env_var_name in ["WML_URL", "WML_PROJECT_ID", "WML_APIKEY"]:
            env_var = os.environ.get(env_var_name)
            assert env_var, (
                f"Error while trying to run 'WMLInferenceEngine'. "
                f"Please set the env variable: '{env_var_name}', or "
                f"directly provide an instance of ibm-watsonx-ai 'Credentials' "
                f"to the engine."
            )

            name = env_var_name.lower().replace("wml_", "")
            credentials[name] = env_var

        return credentials

    def _initialize_wml_client(self):
        from ibm_watsonx_ai.client import APIClient

        if self.credentials is None:
            self.credentials = self._read_wml_credentials_from_env()

        client = APIClient(credentials=self.credentials)
        client.set.default_project(self.credentials["project_id"])
        return client

    def prepare(self):
        if self.client is None:
            self.client = self._initialize_wml_client()

        self._set_inference_parameters()

    def verify(self):
        assert (
            self.model_name
            or self.deployment_id
            and not (self.model_name and self.deployment_id)
        ), "Either 'model_name' or 'deployment_id' must be specified, but not both at the same time."
        super().verify()

    def _infer(self, dataset):
        from ibm_watsonx_ai.foundation_models import ModelInference

        model = ModelInference(
            model_id=self.model_name,
            deployment_id=self.deployment_id,
            api_client=self.client,
        )

        return [
            model.generate_text(
                prompt=instance["source"],
                params=self.to_dict([WMLInferenceEngineParamsMixin], keep_empty=False),
            )
            for instance in dataset
        ]