add reranker

This commit is contained in:
PeterGriffinJin
2025-04-08 00:37:39 +00:00
parent 04d4152575
commit e23b879116
4 changed files with 330 additions and 29 deletions

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@@ -0,0 +1,161 @@
import argparse
from collections import defaultdict
from typing import Optional
from dataclasses import dataclass, field
from sentence_transformers import CrossEncoder
import torch
from transformers import HfArgumentParser
import numpy as np
import uvicorn
from fastapi import FastAPI
from pydantic import BaseModel
class BaseCrossEncoder:
def __init__(self, model, batch_size=32, device="cuda"):
self.model = model
self.batch_size = batch_size
self.model.to(device)
def _passage_to_string(self, doc_item):
if "document" not in doc_item:
content = doc_item['contents']
else:
content = doc_item['document']['contents']
title = content.split("\n")[0]
text = "\n".join(content.split("\n")[1:])
return f"(Title: {title}) {text}"
def rerank(self,
queries: list[str],
documents: list[list[dict]]):
"""
Assume documents is a list of list of dicts, where each dict is a document with keys "id" and "contents".
This asumption is made to be consistent with the output of the retrieval server.
"""
assert len(queries) == len(documents)
pairs = []
qids = []
for qid, query in enumerate(queries):
for document in documents:
for doc_item in document:
doc = self._passage_to_string(doc_item)
pairs.append((query, doc))
qids.append(qid)
scores = self._predict(pairs)
query_to_doc_scores = defaultdict(list)
assert len(scores) == len(pairs) == len(qids)
for i in range(len(pairs)):
query, doc = pairs[i]
score = scores[i]
qid = qids[i]
query_to_doc_scores[qid].append((doc, score))
sorted_query_to_doc_scores = {}
for query, doc_scores in query_to_doc_scores.items():
sorted_query_to_doc_scores[query] = sorted(doc_scores, key=lambda x: x[1], reverse=True)
return sorted_query_to_doc_scores
def _predict(self, pairs: list[tuple[str, str]]):
raise NotImplementedError
@classmethod
def load(cls, model_name_or_path, **kwargs):
raise NotImplementedError
class SentenceTransformerCrossEncoder(BaseCrossEncoder):
def __init__(self, model, batch_size=32, device="cuda"):
super().__init__(model, batch_size, device)
def _predict(self, pairs: list[tuple[str, str]]):
scores = self.model.predict(pairs, batch_size=self.batch_size)
scores = scores.tolist() if isinstance(scores, torch.Tensor) or isinstance(scores, np.ndarray) else scores
return scores
@classmethod
def load(cls, model_name_or_path, **kwargs):
model = CrossEncoder(model_name_or_path)
return cls(model, **kwargs)
class RerankRequest(BaseModel):
queries: list[str]
documents: list[list[dict]]
rerank_topk: Optional[int] = None
return_scores: bool = False
@dataclass
class RerankerArguments:
max_length: int = field(default=512)
rerank_topk: int = field(default=3)
rerank_model_name_or_path: str = field(default="cross-encoder/ms-marco-MiniLM-L12-v2")
batch_size: int = field(default=32)
reranker_type: str = field(default="sentence_transformer")
def get_reranker(config):
if config.reranker_type == "sentence_transformer":
return SentenceTransformerCrossEncoder.load(
config.rerank_model_name_or_path,
batch_size=config.batch_size,
device="cuda" if torch.cuda.is_available() else "cpu"
)
else:
raise ValueError(f"Unknown reranker type: {config.reranker_type}")
app = FastAPI()
@app.post("/rerank")
def rerank_endpoint(request: RerankRequest):
"""
Endpoint that accepts queries and performs retrieval.
Input format:
{
"queries": ["What is Python?", "Tell me about neural networks."],
"documents": [[doc_item_1, ..., doc_item_k], [doc_item_1, ..., doc_item_k]],
"rerank_topk": 3,
"return_scores": true
}
"""
if not request.rerank_topk:
request.rerank_topk = config.rerank_topk # fallback to default
# Perform batch re reranking
# doc_scores already sorted by score
query_to_doc_scores = reranker.rerank(request.queries, request.documents)
# Format response
resp = []
for _, doc_scores in query_to_doc_scores.items():
doc_scores = doc_scores[:request.rerank_topk]
if request.return_scores:
combined = []
for doc, score in doc_scores:
combined.append({"document": doc, "score": score})
resp.append(combined)
else:
resp.append([doc for doc, _ in doc_scores])
return {"result": resp}
if __name__ == "__main__":
# 1) Build a config (could also parse from arguments).
# In real usage, you'd parse your CLI arguments or environment variables.
parser = HfArgumentParser((RerankerArguments))
config = parser.parse_args_into_dataclasses()[0]
# 2) Instantiate a global retriever so it is loaded once and reused.
reranker = get_reranker(config)
# 3) Launch the server. By default, it listens on http://127.0.0.1:8000
uvicorn.run(app, host="0.0.0.0", port=6980)

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@@ -0,0 +1,123 @@
# pip install -U sentence-transformers
import os
import re
import argparse
from dataclasses import dataclass, field
from typing import List, Optional
from collections import defaultdict
import torch
import numpy as np
from fastapi import FastAPI
from pydantic import BaseModel
from sentence_transformers import CrossEncoder
from retrieval_server import get_retriever, Config as RetrieverConfig
from rerank_server import SentenceTransformerCrossEncoder
app = FastAPI()
def convert_title_format(text):
# Use regex to extract the title and the content
match = re.match(r'\(Title:\s*([^)]+)\)\s*(.+)', text, re.DOTALL)
if match:
title, content = match.groups()
return f'\"{title}\"\n{content}'
else:
return text
# ----------- Combined Request Schema -----------
class SearchRequest(BaseModel):
queries: List[str]
topk_retrieval: Optional[int] = 10
topk_rerank: Optional[int] = 3
return_scores: bool = False
# ----------- Reranker Config Schema -----------
@dataclass
class RerankerArguments:
max_length: int = field(default=512)
rerank_topk: int = field(default=3)
rerank_model_name_or_path: str = field(default="cross-encoder/ms-marco-MiniLM-L12-v2")
batch_size: int = field(default=32)
reranker_type: str = field(default="sentence_transformer")
def get_reranker(config):
if config.reranker_type == "sentence_transformer":
return SentenceTransformerCrossEncoder.load(
config.rerank_model_name_or_path,
batch_size=config.batch_size,
device="cuda" if torch.cuda.is_available() else "cpu"
)
else:
raise ValueError(f"Unknown reranker type: {config.reranker_type}")
# ----------- Endpoint -----------
@app.post("/retrieve")
def search_endpoint(request: SearchRequest):
# Step 1: Retrieve documents
retrieved_docs = retriever.batch_search(
query_list=request.queries,
num=request.topk_retrieval,
return_score=False
)
# Step 2: Rerank
reranked = reranker.rerank(request.queries, retrieved_docs)
# Step 3: Format response
response = []
for i, doc_scores in reranked.items():
doc_scores = doc_scores[:request.topk_rerank]
if request.return_scores:
combined = []
for doc, score in doc_scores:
combined.append({"document": convert_title_format(doc), "score": score})
response.append(combined)
else:
response.append([convert_title_format(doc) for doc, _ in doc_scores])
return {"result": response}
if __name__ == "__main__":
parser = argparse.ArgumentParser(description="Launch the local faiss retriever.")
# retriever
parser.add_argument("--index_path", type=str, default="/home/peterjin/mnt/index/wiki-18/e5_Flat.index", help="Corpus indexing file.")
parser.add_argument("--corpus_path", type=str, default="/home/peterjin/mnt/data/retrieval-corpus/wiki-18.jsonl", help="Local corpus file.")
parser.add_argument("--retrieval_topk", type=int, default=10, help="Number of retrieved passages for one query.")
parser.add_argument("--retriever_name", type=str, default="e5", help="Name of the retriever model.")
parser.add_argument("--retriever_model", type=str, default="intfloat/e5-base-v2", help="Path of the retriever model.")
parser.add_argument('--faiss_gpu', action='store_true', help='Use GPU for computation')
# reranker
parser.add_argument("--reranking_topk", type=int, default=3, help="Number of reranked passages for one query.")
parser.add_argument("--reranker_model", type=str, default="cross-encoder/ms-marco-MiniLM-L12-v2", help="Path of the reranker model.")
parser.add_argument("--reranker_batch_size", type=int, default=32, help="Batch size for the reranker inference.")
args = parser.parse_args()
# ----------- Load Retriever and Reranker -----------
retriever_config = RetrieverConfig(
retrieval_method = args.retriever_name,
index_path=args.index_path,
corpus_path=args.corpus_path,
retrieval_topk=args.retrieval_topk,
faiss_gpu=args.faiss_gpu,
retrieval_model_path=args.retriever_model,
retrieval_pooling_method="mean",
retrieval_query_max_length=256,
retrieval_use_fp16=True,
retrieval_batch_size=512,
)
retriever = get_retriever(retriever_config)
reranker_config = RerankerArguments(
rerank_topk = args.reranking_topk,
rerank_model_name_or_path = args.reranker_model,
batch_size = args.reranker_batch_size,
)
reranker = get_reranker(reranker_config)
import uvicorn
uvicorn.run(app, host="0.0.0.0", port=8000)

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@@ -15,17 +15,6 @@ import uvicorn
from fastapi import FastAPI
from pydantic import BaseModel
parser = argparse.ArgumentParser(description="Launch the local faiss retriever.")
parser.add_argument("--index_path", type=str, default="/home/peterjin/mnt/index/wiki-18/e5_Flat.index", help="Corpus indexing file.")
parser.add_argument("--corpus_path", type=str, default="/home/peterjin/mnt/data/retrieval-corpus/wiki-18.jsonl", help="Local corpus file.")
parser.add_argument("--topk", type=int, default=3, help="Number of retrieved passages for one query.")
parser.add_argument("--retriever_name", type=str, default="e5", help="Name of the retriever model.")
parser.add_argument("--retriever_model", type=str, default="intfloat/e5-base-v2", help="Path of the retriever model.")
parser.add_argument('--faiss_gpu', action='store_true', help='Use GPU for computation')
args = parser.parse_args()
def load_corpus(corpus_path: str):
corpus = datasets.load_dataset(
'json',
@@ -334,24 +323,6 @@ class QueryRequest(BaseModel):
app = FastAPI()
# 1) Build a config (could also parse from arguments).
# In real usage, you'd parse your CLI arguments or environment variables.
config = Config(
retrieval_method = args.retriever_name, # or "dense"
index_path=args.index_path,
corpus_path=args.corpus_path,
retrieval_topk=args.topk,
faiss_gpu=args.faiss_gpu,
retrieval_model_path=args.retriever_model,
retrieval_pooling_method="mean",
retrieval_query_max_length=256,
retrieval_use_fp16=True,
retrieval_batch_size=512,
)
# 2) Instantiate a global retriever so it is loaded once and reused.
retriever = get_retriever(config)
@app.post("/retrieve")
def retrieve_endpoint(request: QueryRequest):
"""
@@ -388,5 +359,34 @@ def retrieve_endpoint(request: QueryRequest):
if __name__ == "__main__":
parser = argparse.ArgumentParser(description="Launch the local faiss retriever.")
parser.add_argument("--index_path", type=str, default="/home/peterjin/mnt/index/wiki-18/e5_Flat.index", help="Corpus indexing file.")
parser.add_argument("--corpus_path", type=str, default="/home/peterjin/mnt/data/retrieval-corpus/wiki-18.jsonl", help="Local corpus file.")
parser.add_argument("--topk", type=int, default=3, help="Number of retrieved passages for one query.")
parser.add_argument("--retriever_name", type=str, default="e5", help="Name of the retriever model.")
parser.add_argument("--retriever_model", type=str, default="intfloat/e5-base-v2", help="Path of the retriever model.")
parser.add_argument('--faiss_gpu', action='store_true', help='Use GPU for computation')
args = parser.parse_args()
# 1) Build a config (could also parse from arguments).
# In real usage, you'd parse your CLI arguments or environment variables.
config = Config(
retrieval_method = args.retriever_name, # or "dense"
index_path=args.index_path,
corpus_path=args.corpus_path,
retrieval_topk=args.topk,
faiss_gpu=args.faiss_gpu,
retrieval_model_path=args.retriever_model,
retrieval_pooling_method="mean",
retrieval_query_max_length=256,
retrieval_use_fp16=True,
retrieval_batch_size=512,
)
# 2) Instantiate a global retriever so it is loaded once and reused.
retriever = get_retriever(config)
# 3) Launch the server. By default, it listens on http://127.0.0.1:8000
uvicorn.run(app, host="0.0.0.0", port=8000)