[Dataset]: Iterate through benchmark dataset once (#48)

issue link: #44

### Summary:
* `--max-requests` CLI parameter now supports the `dataset` value.
* `MaxRequestsType(ParamType)` is used as a custom `click` param type to
validate input data
* `RequestGenerator(ABC)` now includes the abstract `__len__` that
corresponds to the length of the dataset if it is supported.
* Unit tests are added
    * Smoke tests are added
* `guidellm/utils/text.py` is fixed. There is no reason to check if the
file start with the `'http'` string. Basically this is a Bug since you
never read a text file properly because of old `if/else` condition.

---------

Co-authored-by: Dmytro Parfeniuk <parfeniukinik@gmail.com>

Author: parfeniukink

pyproject.toml

@@ -104,6 +104,10 @@ exclude = ["venv", ".tox"]
 # Check: https://mypy.readthedocs.io/en/latest/config_file.html#import-discovery
 follow_imports = 'silent'
 
+[[tool.mypy.overrides]]
+module = ["datasets.*"]
+ignore_missing_imports=true
+
 
 [tool.ruff]
 line-length = 88
@@ -122,6 +126,8 @@ ignore = [
     "ISC001",
     "TCH002",
     "PLW1514", # allow Path.open without encoding
+    "RET505", # allow `else` blocks
+    "RET506" # allow `else` blocks
 
 ]
 select = [

src/guidellm/backend/openai.py

@@ -111,6 +111,7 @@ async def make_request(
             stream=True,
             **request_args,
         )
+
         token_count = 0
         async for chunk in stream:
             choice = chunk.choices[0]

src/guidellm/executor/profile_generator.py

@@ -1,7 +1,8 @@
-from typing import Any, Dict, Literal, Optional, Sequence, Union, get_args
+from typing import Any, Dict, List, Literal, Optional, Sequence, Union, get_args
 
 import numpy as np
 from loguru import logger
+from numpy._typing import NDArray
 from pydantic import Field
 
 from guidellm.config import settings
@@ -190,12 +191,14 @@ def next(self, current_report: TextGenerationBenchmarkReport) -> Optional[Profil
         elif self.mode == "sweep":
             profile = self.create_sweep_profile(
                 self.generated_count,
-                sync_benchmark=current_report.benchmarks[0]
-                if current_report.benchmarks
-                else None,
-                throughput_benchmark=current_report.benchmarks[1]
-                if len(current_report.benchmarks) > 1
-                else None,
+                sync_benchmark=(
+                    current_report.benchmarks[0] if current_report.benchmarks else None
+                ),
+                throughput_benchmark=(
+                    current_report.benchmarks[1]
+                    if len(current_report.benchmarks) > 1
+                    else None
+                ),
             )
         else:
             err = ValueError(f"Invalid mode: {self.mode}")
@@ -333,11 +336,15 @@ def create_sweep_profile(
 
         min_rate = sync_benchmark.completed_request_rate
         max_rate = throughput_benchmark.completed_request_rate
-        intermediate_rates = list(
+        intermediate_rates: List[NDArray] = list(
             np.linspace(min_rate, max_rate, settings.num_sweep_profiles + 1)
         )[1:]
 
         return Profile(
             load_gen_mode="constant",
-            load_gen_rate=intermediate_rates[index - 2],
+            load_gen_rate=(
+                float(load_gen_rate)
+                if (load_gen_rate := intermediate_rates[index - 2])
+                else 1.0  # the fallback value
+            ),
         )

src/guidellm/main.py

@@ -1,5 +1,5 @@
 import asyncio
-from typing import Literal, Optional, get_args
+from typing import Literal, Optional, Union, get_args
 
 import click
 from loguru import logger
@@ -13,7 +13,7 @@
     TransformersDatasetRequestGenerator,
 )
 from guidellm.request.base import RequestGenerator
-from guidellm.utils import BenchmarkReportProgress
+from guidellm.utils import BenchmarkReportProgress, cli_params
 
 __all__ = ["generate_benchmark_report"]
 
@@ -120,7 +120,7 @@
 )
 @click.option(
     "--max-requests",
-    type=int,
+    type=cli_params.MAX_REQUESTS,
     default=None,
     help=(
         "The maximum number of requests for each benchmark run. "
@@ -161,7 +161,7 @@ def generate_benchmark_report_cli(
     rate_type: ProfileGenerationMode,
     rate: Optional[float],
     max_seconds: Optional[int],
-    max_requests: Optional[int],
+    max_requests: Union[Literal["dataset"], int, None],
     output_path: str,
     enable_continuous_refresh: bool,
 ):
@@ -194,7 +194,7 @@ def generate_benchmark_report(
     rate_type: ProfileGenerationMode,
     rate: Optional[float],
     max_seconds: Optional[int],
-    max_requests: Optional[int],
+    max_requests: Union[Literal["dataset"], int, None],
     output_path: str,
     cont_refresh_table: bool,
 ) -> GuidanceReport:
@@ -256,13 +256,18 @@ def generate_benchmark_report(
     else:
         raise ValueError(f"Unknown data type: {data_type}")
 
+    if data_type == "emulated" and max_requests == "dataset":
+        raise ValueError("Cannot use 'dataset' for emulated data")
+
     # Create executor
     executor = Executor(
         backend=backend_inst,
         request_generator=request_generator,
         mode=rate_type,
         rate=rate if rate_type in ("constant", "poisson") else None,
-        max_number=max_requests,
+        max_number=(
+            len(request_generator) if max_requests == "dataset" else max_requests
+        ),
         max_duration=max_seconds,
     )
 

src/guidellm/request/base.py

@@ -105,6 +105,21 @@ def __iter__(self) -> Iterator[TextGenerationRequest]:
             while not self._stop_event.is_set():
                 yield self.create_item()
 
+    @abstractmethod
+    def __len__(self) -> int:
+        """
+        Abstract method to get the length of the collection to be generated.
+        """
+
+    @abstractmethod
+    def create_item(self) -> TextGenerationRequest:
+        """
+        Abstract method to create a new result request item.
+
+        :return: A new result request.
+        :rtype: TextGenerationRequest
+        """
+
     @property
     def type_(self) -> str:
         """
@@ -155,15 +170,6 @@ def async_queue_size(self) -> int:
         """
         return self._async_queue_size
 
-    @abstractmethod
-    def create_item(self) -> TextGenerationRequest:
-        """
-        Abstract method to create a new result request item.
-
-        :return: A new result request.
-        :rtype: TextGenerationRequest
-        """
-
     def stop(self):
         """
         Stop the background task that populates the queue.

src/guidellm/request/emulated.py

@@ -339,6 +339,12 @@ def __init__(
             async_queue_size=async_queue_size,
         )
 
+    def __len__(self) -> int:
+        raise NotImplementedError(
+            "Can't get the length of the emulated dataset. "
+            "Check the `--data-type` CLI parameter."
+        )
+
     def create_item(self) -> TextGenerationRequest:
         """
         Create a new text generation request item from the data.

src/guidellm/request/file.py

@@ -54,6 +54,13 @@ def __init__(
             async_queue_size=async_queue_size,
         )
 
+    def __len__(self) -> int:
+        """
+        Return the number of text lines.
+        """
+
+        return len(self._data)
+
     def create_item(self) -> TextGenerationRequest:
         """
         Create a new result request item from the data.

src/guidellm/request/transformers.py

@@ -1,12 +1,7 @@
 from pathlib import Path
 from typing import Optional, Union
 
-from datasets import (  # type: ignore  # noqa: PGH003
-    Dataset,
-    DatasetDict,
-    IterableDataset,
-    IterableDatasetDict,
-)
+from datasets import Dataset, DatasetDict, IterableDataset, IterableDatasetDict
 from loguru import logger
 from transformers import PreTrainedTokenizer  # type: ignore  # noqa: PGH003
 
@@ -57,7 +52,9 @@ def __init__(
         self._column = column
         self._kwargs = kwargs
 
-        self._hf_dataset = load_transformers_dataset(dataset, split=split, **kwargs)
+        self._hf_dataset: Union[Dataset, IterableDataset] = load_transformers_dataset(
+            dataset, split=split, **kwargs
+        )
         self._hf_column = resolve_transformers_dataset_column(
             self._hf_dataset, column=column
         )
@@ -73,6 +70,12 @@ def __init__(
             async_queue_size=async_queue_size,
         )
 
+    def __len__(self) -> int:
+        if not isinstance(self._hf_dataset, Dataset):
+            raise ValueError("Can't get dataset size for IterableDataset object")
+        else:
+            return len(self._hf_dataset)
+
     def create_item(self) -> TextGenerationRequest:
         """
         Create a new result request item from the dataset.

src/guidellm/utils/cli_params.py

@@ -0,0 +1,34 @@
+"""
+This module includes custom CLI parameters for the `click` package.
+"""
+
+from typing import Any, Optional
+
+from click import Context, Parameter, ParamType
+
+__all__ = ["MAX_REQUESTS"]
+
+
+class MaxRequestsType(ParamType):
+    """
+    Catch the `dataset` string parameter to determine the behavior of the Scheduler.
+    """
+
+    name = "max_requests"
+
+    def convert(
+        self, value: Any, param: Optional[Parameter], ctx: Optional[Context]
+    ) -> Any:
+        if isinstance(value, int):
+            return value
+
+        try:
+            return int(value)
+        except ValueError:
+            if value == "dataset":
+                return value
+            else:
+                self.fail(f"{value} is not a valid integer or 'dataset'", param, ctx)
+
+
+MAX_REQUESTS = MaxRequestsType()

src/guidellm/utils/progress.py

@@ -139,6 +139,7 @@ def update_benchmark(
         :type req_per_sec: float
         :raises ValueError: If trying to update a completed benchmark.
         """
+
         if self.benchmark_tasks_completed[index]:
             err = ValueError(f"Benchmark {index} already completed")
             logger.error("Error updating benchmark: {}", err)
@@ -162,9 +163,11 @@ def update_benchmark(
             total=completed_total,
             completed=completed_count if not completed else completed_total,
             req_per_sec=(f"{req_per_sec:.2f}" if req_per_sec else "#.##"),
-            start_time_str=datetime.fromtimestamp(start_time).strftime("%H:%M:%S")
-            if start_time
-            else "--:--:--",
+            start_time_str=(
+                datetime.fromtimestamp(start_time).strftime("%H:%M:%S")
+                if start_time
+                else "--:--:--"
+            ),
         )
         logger.debug(
             "Updated benchmark task at index {}: {}% complete",