demo-code-search/code_search/index/helper.py

147 lines
5.4 KiB
Python

from abc import abstractmethod
from typing import Union, List, Optional
from sentence_transformers import SentenceTransformer
from transformers import AutoTokenizer, AutoModel
import numpy as np
import torch
import re
from code_search.model.unixcoder import UniXcoder
class BaseEmbeddingsProvider:
@abstractmethod
def embed_code(
self, code: Optional[str] = None, docstring: Optional[str] = None
) -> np.array:
"""Converts code and/or docstring to vector"""
class AutoModelEmbeddingsProvider(BaseEmbeddingsProvider):
def __init__(
self,
model_name: str = "microsoft/codebert-base",
tokenizer_name: Optional[str] = None,
max_tokens: int = 512,
):
if tokenizer_name is None:
tokenizer_name = model_name
self.tokenizer = AutoTokenizer.from_pretrained(tokenizer_name)
self.model = AutoModel.from_pretrained(model_name)
self.max_tokens = max_tokens
self.model_name = model_name
def embed_code(
self, code: Optional[str] = None, docstring: Optional[str] = None
) -> np.array:
token_ids = self.get_token_ids(code, docstring)[:512]
context_embeddings = (
self.model(torch.tensor(token_ids)[None, :])[0].squeeze().detach().numpy()
)
if 1 == len(context_embeddings.shape):
return context_embeddings
return np.mean(context_embeddings, axis=0)
def get_token_ids(
self, code: Optional[str] = None, docstring: Optional[str] = None
) -> Union[int, List[int]]:
tokens = self.get_tokens(code, docstring)
tokens_ids = self.tokenizer.convert_tokens_to_ids(tokens)
return tokens_ids
def get_tokens(
self, code: Optional[str] = None, docstring: Optional[str] = None
) -> List[str]:
# Maximum number of tokens has to include the separators used by CodeBERT
max_tokens = self.max_tokens - 3
code_tokens = []
if code is not None:
code_tokens = self.tokenizer.tokenize(
code, max_length=max_tokens, truncation=True
)
docstring_tokens = []
if docstring is not None:
docstring_tokens = self.tokenizer.tokenize(
docstring, max_length=max_tokens, truncation=True
)
# If both code and docstring is provided, we need to cut off some
# tokens above the limit. Here there preference is to remove the code
# as it should be longer in general.
n_code_tokens, n_doc_tokens = (
min(len(code_tokens), max_tokens),
min(len(docstring_tokens), max_tokens),
)
n_code_tokens -= n_doc_tokens
# Build all the tokens using some possible separators. The separators
# are aligned to CodeBERT model, but if a selected transformer does not
# have them, everything should also work.
tokens = []
if hasattr(self.tokenizer, "cls_token"):
tokens.append(self.tokenizer.cls_token)
tokens.extend(code_tokens[:n_code_tokens])
if hasattr(self.tokenizer, "sep_token"):
tokens.append(self.tokenizer.sep_token)
tokens.extend(docstring_tokens[:n_doc_tokens])
if hasattr(self.tokenizer, "eos_token"):
tokens.append(self.tokenizer.eos_token)
return tokens
def __str__(self):
return self.model_name
class UniXcoderEmbeddingsProvider(BaseEmbeddingsProvider):
def __init__(self, device: Optional[str] = None):
default_device = "cuda" if torch.cuda.is_available() else "cpu"
self.device = torch.device(default_device if device is None else device)
self.model = UniXcoder("microsoft/unixcoder-base")
self.model.to(self.device)
self.model_name = "microsoft/unixcoder-base"
def embed_code(
self, code: Optional[str] = None, docstring: Optional[str] = None
) -> np.array:
tokens_ids = self.model.tokenize(
[f"{docstring or ''} {code or ''}"], max_length=512, mode="<encoder-only>"
)
source_ids = torch.tensor(tokens_ids).to(self.device)
_, func_embedding = self.model(source_ids)
vector = func_embedding.detach().cpu().numpy()[0]
return vector
class SentenceTransformerEmbeddingsProvider(BaseEmbeddingsProvider):
camel_case_regex = re.compile(r"([a-z\s])([A-Z])")
underscore_regex = re.compile(r"([a-z])_([a-z])")
special_chars_regex = re.compile(r"\(|\)|\{|\}|\<|\>|\[|\]|\&|::|;")
method_call_regex = re.compile(r"\.([a-z])")
multiple_white_char_regex = re.compile(r"\s{2,}")
def __init__(self, sentence_transformer_name: str):
self.model = SentenceTransformer(sentence_transformer_name)
self.model_name = sentence_transformer_name
def embed_code(
self, code: Optional[str] = None, docstring: Optional[str] = None
) -> np.array:
inputs = []
if docstring is not None:
inputs.append(docstring)
if code is not None:
inputs.append(code)
return self.model.encode(self._preprocess_text(" ".join(inputs)))
def _preprocess_text(self, text: str) -> str:
text = self.camel_case_regex.sub("\\1 \\2", text)
text = self.underscore_regex.sub("\\1 \\2", text)
text = self.special_chars_regex.sub(" ", text)
text = self.method_call_regex.sub(" \\1", text)
text = self.multiple_white_char_regex.sub(" ", text)
return text