Source code for langchain_community.utilities.google_scholar
"""调用谷歌学术搜索的工具。"""
from typing import Dict, Optional
from langchain_core.pydantic_v1 import BaseModel, Extra, root_validator
from langchain_core.utils import get_from_dict_or_env
[docs]class GoogleScholarAPIWrapper(BaseModel):
"""包装器用于Google Scholar API
您可以通过在以下网址注册来创建serpapi密钥:https://serpapi.com/users/sign_up。
该包装器使用serpapi python包:
https://serpapi.com/integrations/python#search-google-scholar
要使用,您应该设置环境变量``SERP_API_KEY``
为您的API密钥,或将`serp_api_key`作为命名参数传递给构造函数。
属性:
top_k_results:从google-scholar查询中返回的结果数量。
默认情况下返回前10个结果。
hl:属性定义用于Google Scholar搜索的语言。
这是一个两字母的语言代码。
(例如,en表示英语,es表示西班牙语,fr表示法语)。请访问
Google语言页面查看支持的Google语言的完整列表:
https://serpapi.com/google-languages
lr:属性定义要限制搜索的一个或多个语言。
它使用lang_{两字母语言代码}来指定语言
并使用|作为分隔符。(例如,lang_fr|lang_de将仅搜索法语
和德语页面)。请访问Google lr语言页面查看完整的
支持语言列表:https://serpapi.com/google-lr-languages
示例:
.. code-block:: python
from langchain_community.utilities import GoogleScholarAPIWrapper
google_scholar = GoogleScholarAPIWrapper()
google_scholar.run('langchain')"""
top_k_results: int = 10
hl: str = "en"
lr: str = "lang_en"
serp_api_key: Optional[str] = None
class Config:
"""此pydantic对象的配置。"""
extra = Extra.forbid
@root_validator()
def validate_environment(cls, values: Dict) -> Dict:
"""验证环境中是否存在API密钥和Python包。"""
serp_api_key = get_from_dict_or_env(values, "serp_api_key", "SERP_API_KEY")
values["SERP_API_KEY"] = serp_api_key
try:
from serpapi import GoogleScholarSearch
except ImportError:
raise ImportError(
"google-search-results is not installed. "
"Please install it with `pip install google-search-results"
">=2.4.2`"
)
GoogleScholarSearch.SERP_API_KEY = serp_api_key
values["google_scholar_engine"] = GoogleScholarSearch
return values
[docs] def run(self, query: str) -> str:
"""通过GoogleSearchScholar运行查询并解析结果。"""
total_results = []
page = 0
while page < max((self.top_k_results - 20), 1):
# We are getting 20 results from every page
# which is the max in order to reduce the number of API CALLS.
# 0 is the first page of results, 20 is the 2nd page of results,
# 40 is the 3rd page of results, etc.
results = (
self.google_scholar_engine( # type: ignore
{
"q": query,
"start": page,
"hl": self.hl,
"num": min(
self.top_k_results, 20
), # if top_k_result is less than 20.
"lr": self.lr,
}
)
.get_dict()
.get("organic_results", [])
)
total_results.extend(results)
if not results: # No need to search for more pages if current page
# has returned no results
break
page += 20
if (
self.top_k_results % 20 != 0 and page > 20 and total_results
): # From the last page we would only need top_k_results%20 results
# if k is not divisible by 20.
results = (
self.google_scholar_engine( # type: ignore
{
"q": query,
"start": page,
"num": self.top_k_results % 20,
"hl": self.hl,
"lr": self.lr,
}
)
.get_dict()
.get("organic_results", [])
)
total_results.extend(results)
if not total_results:
return "No good Google Scholar Result was found"
docs = [
f"Title: {result.get('title','')}\n"
f"Authors: {','.join([author.get('name') for author in result.get('publication_info',{}).get('authors',[])])}\n" # noqa: E501
f"Summary: {result.get('publication_info',{}).get('summary','')}\n"
f"Total-Citations: {result.get('inline_links',{}).get('cited_by',{}).get('total','')}" # noqa: E501
for result in total_results
]
return "\n\n".join(docs)