refine the benchmark eval UX (#156)

## What does this PR do?
Refine the benchmark eval CLI to have a better user experience to run
benchmark eval on some standard benchmarks.

The benchmarks need to be defined as resource in the distro template

improvements include:
- user don't need to pass in arbitrary eval-task-config, they only need
to pass in the list of benchmarks they'd like to eval, the model id to
be evaluated on and the output dir to store the eval results
- output aggregate results to the output file. aggregate results are
typically what user care most


## Test Plan
spin up a llama stack server with eval benchmarks defined
run `llama-stack-client --endpoint xxxx eval run-benchmark
"meta-reference-simpleqa" --model_id "meta-llama/Llama-3.1-8B-Instruct"
--output_dir "/home/markchen1015/" --num_examples 5`

return 
<img width="1284" alt="Screenshot 2025-02-20 at 4 29 35 PM"
src="https://github.com/user-attachments/assets/624e0b59-fcbf-46b8-b2cf-2a36bba9aee5"
/>


what are inside the output file

<img width="1436" alt="Screenshot 2025-02-20 at 4 30 08 PM"
src="https://github.com/user-attachments/assets/d0a370ff-df98-4fbf-93ba-78104838d02b"
/>


<img width="1444" alt="Screenshot 2025-02-20 at 4 17 05 PM"
src="https://github.com/user-attachments/assets/7da65c03-cc03-48f3-be70-1489a9430f18"
/>

Author: SLR722

src/llama_stack_client/lib/cli/eval/run_benchmark.py

@@ -13,15 +13,22 @@
 from tqdm.rich import tqdm
 
 from ..common.utils import create_bar_chart
+from .utils import (
+    aggregate_accuracy,
+    aggregate_average,
+    aggregate_categorical_count,
+    aggregate_median,
+)
 
 
 @click.command("run-benchmark")
-@click.argument("eval-task-ids", nargs=-1, required=True)
+@click.argument("benchmark-ids", nargs=-1, required=True)
 @click.option(
-    "--eval-task-config",
+    "--model-id",
     required=True,
-    help="Path to the eval task config file in JSON format",
-    type=click.Path(exists=True),
+    help="model id to run the benchmark eval on",
+    default=None,
+    type=str,
 )
 @click.option(
     "--output-dir",
@@ -35,6 +42,34 @@
     default=None,
     type=int,
 )
+@click.option(
+    "--temperature",
+    required=False,
+    help="temperature in the sampling params to run generation",
+    default=0.0,
+    type=float,
+)
+@click.option(
+    "--max-tokens",
+    required=False,
+    help="max-tokens in the sampling params to run generation",
+    default=4096,
+    type=int,
+)
+@click.option(
+    "--top-p",
+    required=False,
+    help="top-p in the sampling params to run generation",
+    default=0.9,
+    type=float,
+)
+@click.option(
+    "--repeat-penalty",
+    required=False,
+    help="repeat-penalty in the sampling params to run generation",
+    default=1.0,
+    type=float,
+)
 @click.option(
     "--visualize",
     is_flag=True,
@@ -44,36 +79,50 @@
 @click.pass_context
 def run_benchmark(
     ctx,
-    eval_task_ids: tuple[str, ...],
-    eval_task_config: str,
+    benchmark_ids: tuple[str, ...],
+    model_id: str,
     output_dir: str,
     num_examples: Optional[int],
+    temperature: float,
+    max_tokens: int,
+    top_p: float,
+    repeat_penalty: float,
     visualize: bool,
 ):
     """Run a evaluation benchmark task"""
 
     client = ctx.obj["client"]
 
-    for eval_task_id in eval_task_ids:
-        eval_task = client.eval_tasks.retrieve(name=eval_task_id)
-        scoring_functions = eval_task.scoring_functions
-        dataset_id = eval_task.dataset_id
+    for benchmark_id in benchmark_ids:
+        benchmark = client.benchmarks.retrieve(benchmark_id=benchmark_id)
+        scoring_functions = benchmark.scoring_functions
+        dataset_id = benchmark.dataset_id
 
         rows = client.datasetio.get_rows_paginated(
-            dataset_id=dataset_id, rows_in_page=-1 if num_examples is None else num_examples
+            dataset_id=dataset_id,
+            rows_in_page=-1 if num_examples is None else num_examples,
         )
 
-        with open(eval_task_config, "r") as f:
-            eval_task_config = json.load(f)
-
         output_res = {}
 
-        for r in tqdm(rows.rows):
-            eval_res = client.eval.evaluate_rows(
-                task_id=eval_task_id,
+        for i, r in enumerate(tqdm(rows.rows)):
+            eval_res = client.eval.evaluate_rows_alpha(
+                benchmark_id=benchmark_id,
                 input_rows=[r],
                 scoring_functions=scoring_functions,
-                task_config=eval_task_config,
+                task_config={
+                    "type": "benchmark",
+                    "eval_candidate": {
+                        "type": "model",
+                        "model": model_id,
+                        "sampling_params": {
+                            "temperature": temperature,
+                            "max_tokens": max_tokens,
+                            "top_p": top_p,
+                            "repeat_penalty": repeat_penalty,
+                        },
+                    },
+                },
             )
             for k in r.keys():
                 if k not in output_res:
@@ -90,20 +139,55 @@ def run_benchmark(
                     output_res[scoring_fn] = []
                 output_res[scoring_fn].append(eval_res.scores[scoring_fn].score_rows[0])
 
+                aggregation_functions = client.scoring_functions.retrieve(
+                    scoring_fn_id=scoring_fn
+                ).params.aggregation_functions
+
+                # only output the aggregation result for the last row
+                if i == len(rows.rows) - 1:
+                    for aggregation_function in aggregation_functions:
+                        scoring_results = output_res[scoring_fn]
+                        if aggregation_function == "categorical_count":
+                            output_res[scoring_fn].append(aggregate_categorical_count(scoring_results))
+                        elif aggregation_function == "average":
+                            output_res[scoring_fn].append(aggregate_average(scoring_results))
+                        elif aggregation_function == "median":
+                            output_res[scoring_fn].append(aggregate_median(scoring_results))
+                        elif aggregation_function == "accuracy":
+                            output_res[scoring_fn].append(aggregate_accuracy(scoring_results))
+                        else:
+                            raise NotImplementedError(
+                                f"Aggregation function {aggregation_function} is not supported yet"
+                            )
+
         # Create output directory if it doesn't exist
         os.makedirs(output_dir, exist_ok=True)
         # Save results to JSON file
-        output_file = os.path.join(output_dir, f"{eval_task_id}_results.json")
+        output_file = os.path.join(output_dir, f"{benchmark_id}_results.json")
         with open(output_file, "w") as f:
             json.dump(output_res, f, indent=2)
 
         rprint(f"[green]✓[/green] Results saved to: [blue]{output_file}[/blue]!\n")
 
         if visualize:
             for scoring_fn in scoring_functions:
-                res = output_res[scoring_fn]
-                assert len(res) > 0 and "score" in res[0]
-                scores = [str(r["score"]) for r in res]
-                unique_scores = sorted(list(set(scores)))
-                counts = [scores.count(s) for s in unique_scores]
-                create_bar_chart(counts, unique_scores, title=f"{scoring_fn}")
+                aggregation_functions = client.scoring_functions.retrieve(
+                    scoring_fn_id=scoring_fn
+                ).params.aggregation_functions
+
+                for aggregation_function in aggregation_functions:
+                    res = output_res[scoring_fn]
+                    assert len(res) > 0 and "score" in res[0]
+                    if aggregation_function == "categorical_count":
+                        scores = [str(r["score"]) for r in res]
+                        unique_scores = sorted(list(set(scores)))
+                        counts = [scores.count(s) for s in unique_scores]
+                        create_bar_chart(
+                            counts,
+                            unique_scores,
+                            title=f"{scoring_fn}-{aggregation_function}",
+                        )
+                    else:
+                        raise NotImplementedError(
+                            f"Aggregation function {aggregation_function} ius not supported for visualization yet"
+                        )

src/llama_stack_client/lib/cli/eval/utils.py

@@ -0,0 +1,45 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the terms described in the LICENSE file in
+# the root directory of this source tree.
+
+from typing import Any, Dict, List, Union
+
+
+def aggregate_categorical_count(
+    scoring_results: List[Dict[str, Union[bool, float, str, List[object], object, None]]],
+) -> Dict[str, Any]:
+    scores = [str(r["score"]) for r in scoring_results]
+    unique_scores = sorted(list(set(scores)))
+    return {"categorical_count": {s: scores.count(s) for s in unique_scores}}
+
+
+def aggregate_average(
+    scoring_results: List[Dict[str, Union[bool, float, str, List[object], object, None]]],
+) -> Dict[str, Any]:
+    return {
+        "average": sum(result["score"] for result in scoring_results if result["score"] is not None)
+        / len([_ for _ in scoring_results if _["score"] is not None]),
+    }
+
+
+def aggregate_median(
+    scoring_results: List[Dict[str, Union[bool, float, str, List[object], object, None]]],
+) -> Dict[str, Any]:
+    scores = [r["score"] for r in scoring_results if r["score"] is not None]
+    median = statistics.median(scores) if scores else None
+    return {"median": median}
+
+
+def aggregate_accuracy(
+    scoring_results: List[Dict[str, Union[bool, float, str, List[object], object, None]]],
+) -> Dict[str, Any]:
+    num_correct = sum(result["score"] for result in scoring_results)
+    avg_score = num_correct / len(scoring_results)
+
+    return {
+        "accuracy": avg_score,
+        "num_correct": num_correct,
+        "num_total": len(scoring_results),
+    }