mirror of
https://github.com/hwchase17/langchain
synced 2024-11-02 09:40:22 +00:00
125 lines
4.2 KiB
Python
125 lines
4.2 KiB
Python
"""Util that calls Wikipedia."""
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import logging
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from typing import Any, Dict, Iterator, List, Optional
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from langchain_core.documents import Document
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from langchain_core.pydantic_v1 import BaseModel, root_validator
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logger = logging.getLogger(__name__)
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WIKIPEDIA_MAX_QUERY_LENGTH = 300
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class WikipediaAPIWrapper(BaseModel):
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"""Wrapper around WikipediaAPI.
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To use, you should have the ``wikipedia`` python package installed.
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This wrapper will use the Wikipedia API to conduct searches and
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fetch page summaries. By default, it will return the page summaries
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of the top-k results.
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It limits the Document content by doc_content_chars_max.
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"""
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wiki_client: Any #: :meta private:
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top_k_results: int = 3
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lang: str = "en"
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load_all_available_meta: bool = False
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doc_content_chars_max: int = 4000
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@root_validator()
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def validate_environment(cls, values: Dict) -> Dict:
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"""Validate that the python package exists in environment."""
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try:
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import wikipedia
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wikipedia.set_lang(values["lang"])
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values["wiki_client"] = wikipedia
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except ImportError:
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raise ImportError(
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"Could not import wikipedia python package. "
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"Please install it with `pip install wikipedia`."
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)
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return values
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def run(self, query: str) -> str:
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"""Run Wikipedia search and get page summaries."""
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page_titles = self.wiki_client.search(
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query[:WIKIPEDIA_MAX_QUERY_LENGTH], results=self.top_k_results
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)
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summaries = []
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for page_title in page_titles[: self.top_k_results]:
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if wiki_page := self._fetch_page(page_title):
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if summary := self._formatted_page_summary(page_title, wiki_page):
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summaries.append(summary)
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if not summaries:
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return "No good Wikipedia Search Result was found"
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return "\n\n".join(summaries)[: self.doc_content_chars_max]
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@staticmethod
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def _formatted_page_summary(page_title: str, wiki_page: Any) -> Optional[str]:
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return f"Page: {page_title}\nSummary: {wiki_page.summary}"
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def _page_to_document(self, page_title: str, wiki_page: Any) -> Document:
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main_meta = {
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"title": page_title,
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"summary": wiki_page.summary,
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"source": wiki_page.url,
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}
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add_meta = (
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{
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"categories": wiki_page.categories,
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"page_url": wiki_page.url,
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"image_urls": wiki_page.images,
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"related_titles": wiki_page.links,
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"parent_id": wiki_page.parent_id,
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"references": wiki_page.references,
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"revision_id": wiki_page.revision_id,
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"sections": wiki_page.sections,
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}
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if self.load_all_available_meta
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else {}
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)
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doc = Document(
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page_content=wiki_page.content[: self.doc_content_chars_max],
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metadata={
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**main_meta,
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**add_meta,
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},
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)
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return doc
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def _fetch_page(self, page: str) -> Optional[str]:
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try:
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return self.wiki_client.page(title=page, auto_suggest=False)
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except (
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self.wiki_client.exceptions.PageError,
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self.wiki_client.exceptions.DisambiguationError,
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):
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return None
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def load(self, query: str) -> List[Document]:
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"""
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Run Wikipedia search and get the article text plus the meta information.
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See
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Returns: a list of documents.
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"""
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return list(self.lazy_load(query))
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def lazy_load(self, query: str) -> Iterator[Document]:
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"""
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Run Wikipedia search and get the article text plus the meta information.
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See
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Returns: a list of documents.
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"""
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page_titles = self.wiki_client.search(
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query[:WIKIPEDIA_MAX_QUERY_LENGTH], results=self.top_k_results
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)
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for page_title in page_titles[: self.top_k_results]:
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if wiki_page := self._fetch_page(page_title):
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if doc := self._page_to_document(page_title, wiki_page):
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yield doc
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