[Feature] Add support for RAG evaluation (#1154)

Co-authored-by: Deven Patel <deven298@yahoo.com>
Co-authored-by: Deshraj Yadav <deshrajdry@gmail.com>

embedchain/app.py

@@ -1,13 +1,15 @@
 import ast
+import concurrent.futures
 import json
 import logging
 import os
 import sqlite3
 import uuid
-from typing import Any, Optional
+from typing import Any, Optional, Union
 
 import requests
 import yaml
+from tqdm import tqdm
 
 from embedchain.cache import (Config, ExactMatchEvaluation,
                               SearchDistanceEvaluation, cache,
@@ -18,11 +20,15 @@ from embedchain.constants import SQLITE_PATH
 from embedchain.embedchain import EmbedChain
 from embedchain.embedder.base import BaseEmbedder
 from embedchain.embedder.openai import OpenAIEmbedder
+from embedchain.eval.base import BaseMetric
+from embedchain.eval.metrics import (AnswerRelevance, ContextRelevance,
+                                     Groundedness)
 from embedchain.factory import EmbedderFactory, LlmFactory, VectorDBFactory
 from embedchain.helpers.json_serializable import register_deserializable
 from embedchain.llm.base import BaseLlm
 from embedchain.llm.openai import OpenAILlm
 from embedchain.telemetry.posthog import AnonymousTelemetry
+from embedchain.utils.eval import EvalData, EvalMetric
 from embedchain.utils.misc import validate_config
 from embedchain.vectordb.base import BaseVectorDB
 from embedchain.vectordb.chroma import ChromaDB
@@ -455,3 +461,103 @@ class App(EmbedChain):
             chunker=chunker_config_data,
             cache_config=cache_config,
         )
+
+    def _eval(self, dataset: list[EvalData], metric: Union[BaseMetric, str]):
+        """
+        Evaluate the app on a dataset for a given metric.
+        """
+        metric_str = metric.name if isinstance(metric, BaseMetric) else metric
+        eval_class_map = {
+            EvalMetric.CONTEXT_RELEVANCY.value: ContextRelevance,
+            EvalMetric.ANSWER_RELEVANCY.value: AnswerRelevance,
+            EvalMetric.GROUNDEDNESS.value: Groundedness,
+        }
+
+        if metric_str in eval_class_map:
+            return eval_class_map[metric_str]().evaluate(dataset)
+
+        # Handle the case for custom metrics
+        if isinstance(metric, BaseMetric):
+            return metric.evaluate(dataset)
+        else:
+            raise ValueError(f"Invalid metric: {metric}")
+
+    def evaluate(
+        self,
+        questions: Union[str, list[str]],
+        metrics: Optional[list[Union[BaseMetric, str]]] = None,
+        num_workers: int = 4,
+    ):
+        """
+        Evaluate the app on a question.
+
+        param: questions: A question or a list of questions to evaluate.
+        type: questions: Union[str, list[str]]
+        param: metrics: A list of metrics to evaluate. Defaults to all metrics.
+        type: metrics: Optional[list[Union[BaseMetric, str]]]
+        param: num_workers: Number of workers to use for parallel processing.
+        type: num_workers: int
+        return: A dictionary containing the evaluation results.
+        rtype: dict
+        """
+        if "OPENAI_API_KEY" not in os.environ:
+            raise ValueError("Please set the OPENAI_API_KEY environment variable with permission to use `gpt4` model.")
+
+        queries, answers, contexts = [], [], []
+        if isinstance(questions, list):
+            with concurrent.futures.ThreadPoolExecutor(max_workers=num_workers) as executor:
+                future_to_data = {executor.submit(self.query, q, citations=True): q for q in questions}
+                for future in tqdm(
+                    concurrent.futures.as_completed(future_to_data),
+                    total=len(future_to_data),
+                    desc="Getting answer and contexts for questions",
+                ):
+                    question = future_to_data[future]
+                    queries.append(question)
+                    answer, context = future.result()
+                    answers.append(answer)
+                    contexts.append(list(map(lambda x: x[0], context)))
+        else:
+            answer, context = self.query(questions, citations=True)
+            queries = [questions]
+            answers = [answer]
+            contexts = [list(map(lambda x: x[0], context))]
+
+        metrics = metrics or [
+            EvalMetric.CONTEXT_RELEVANCY.value,
+            EvalMetric.ANSWER_RELEVANCY.value,
+            EvalMetric.GROUNDEDNESS.value,
+        ]
+
+        logging.info(f"Collecting data from {len(queries)} questions for evaluation...")
+        dataset = []
+        for q, a, c in zip(queries, answers, contexts):
+            dataset.append(EvalData(question=q, answer=a, contexts=c))
+
+        logging.info(f"Evaluating {len(dataset)} data points...")
+        result = {}
+        with concurrent.futures.ThreadPoolExecutor(max_workers=num_workers) as executor:
+            future_to_metric = {executor.submit(self._eval, dataset, metric): metric for metric in metrics}
+            for future in tqdm(
+                concurrent.futures.as_completed(future_to_metric),
+                total=len(future_to_metric),
+                desc="Evaluating metrics",
+            ):
+                metric = future_to_metric[future]
+                if isinstance(metric, BaseMetric):
+                    result[metric.name] = future.result()
+                else:
+                    result[metric] = future.result()
+
+        if self.config.collect_metrics:
+            telemetry_props = self._telemetry_props
+            metrics_names = []
+            for metric in metrics:
+                if isinstance(metric, BaseMetric):
+                    metrics_names.append(metric.name)
+                else:
+                    metrics_names.append(metric)
+            telemetry_props["metrics"] = metrics_names
+            self.telemetry.capture(event_name="evaluate", properties=telemetry_props)
+
+        return result