Source code for langchain_community.utilities.wikipedia
"""调用维基百科的工具。"""
import logging
from typing import Any, Dict, Iterator, List, Optional
from langchain_core.documents import Document
from langchain_core.pydantic_v1 import BaseModel, root_validator
logger = logging.getLogger(__name__)
WIKIPEDIA_MAX_QUERY_LENGTH = 300
[docs]class WikipediaAPIWrapper(BaseModel):
"""封装了WikipediaAPI。
要使用,您应该已经安装了``wikipedia`` python包。
此封装将使用Wikipedia API 进行搜索和获取页面摘要。默认情况下,它将返回前k个结果的页面摘要。
通过doc_content_chars_max限制文档内容。"""
wiki_client: Any #: :meta private:
top_k_results: int = 3
lang: str = "en"
load_all_available_meta: bool = False
doc_content_chars_max: int = 4000
@root_validator()
def validate_environment(cls, values: Dict) -> Dict:
"""验证Python包是否存在于环境中。"""
try:
import wikipedia
wikipedia.set_lang(values["lang"])
values["wiki_client"] = wikipedia
except ImportError:
raise ImportError(
"Could not import wikipedia python package. "
"Please install it with `pip install wikipedia`."
)
return values
[docs] def run(self, query: str) -> str:
"""运行维基百科搜索并获取页面摘要。"""
page_titles = self.wiki_client.search(
query[:WIKIPEDIA_MAX_QUERY_LENGTH], results=self.top_k_results
)
summaries = []
for page_title in page_titles[: self.top_k_results]:
if wiki_page := self._fetch_page(page_title):
if summary := self._formatted_page_summary(page_title, wiki_page):
summaries.append(summary)
if not summaries:
return "No good Wikipedia Search Result was found"
return "\n\n".join(summaries)[: self.doc_content_chars_max]
@staticmethod
def _formatted_page_summary(page_title: str, wiki_page: Any) -> Optional[str]:
return f"Page: {page_title}\nSummary: {wiki_page.summary}"
def _page_to_document(self, page_title: str, wiki_page: Any) -> Document:
main_meta = {
"title": page_title,
"summary": wiki_page.summary,
"source": wiki_page.url,
}
add_meta = (
{
"categories": wiki_page.categories,
"page_url": wiki_page.url,
"image_urls": wiki_page.images,
"related_titles": wiki_page.links,
"parent_id": wiki_page.parent_id,
"references": wiki_page.references,
"revision_id": wiki_page.revision_id,
"sections": wiki_page.sections,
}
if self.load_all_available_meta
else {}
)
doc = Document(
page_content=wiki_page.content[: self.doc_content_chars_max],
metadata={
**main_meta,
**add_meta,
},
)
return doc
def _fetch_page(self, page: str) -> Optional[str]:
try:
return self.wiki_client.page(title=page, auto_suggest=False)
except (
self.wiki_client.exceptions.PageError,
self.wiki_client.exceptions.DisambiguationError,
):
return None
[docs] def load(self, query: str) -> List[Document]:
"""运行维基百科搜索并获取文章文本以及元信息。
参见
返回:文档列表。
"""
return list(self.lazy_load(query))
[docs] def lazy_load(self, query: str) -> Iterator[Document]:
"""运行维基百科搜索并获取文章文本以及元信息。
参见
返回:文档列表。
"""
page_titles = self.wiki_client.search(
query[:WIKIPEDIA_MAX_QUERY_LENGTH], results=self.top_k_results
)
for page_title in page_titles[: self.top_k_results]:
if wiki_page := self._fetch_page(page_title):
if doc := self._page_to_document(page_title, wiki_page):
yield doc