Redis 向量存储
本笔记本介绍了如何开始使用 Redis 向量存储。
Redis 是一种流行的开源内存数据结构存储,可以用作数据库、缓存、消息代理和队列。它现在包含向量相似性搜索功能,使其适合用作向量存储。
什么是 Redis?
大多数开发人员都熟悉 Redis
。从本质上讲,Redis
是键值系列的 NoSQL 数据库,可用作缓存、消息代理、流处理和主数据库。开发人员选择 Redis
是因为它速度快、拥有庞大的客户端库生态系统,并且已被主要企业部署多年。
在这些传统用例的基础上,Redis
提供了额外的功能,例如搜索和查询功能,允许用户在 Redis
中创建二级索引结构。这使得 Redis
能够成为向量数据库,并且拥有缓存的速度。
Redis 作为向量数据库
Redis
使用压缩的倒排索引进行快速索引,且内存占用量低。它还支持许多高级功能,例如
- 索引 Redis 哈希和
JSON
中的多个字段 - 向量相似性搜索(使用
HNSW
(ANN) 或FLAT
(KNN)) - 向量范围搜索(例如,查找查询向量半径内的所有向量)
- 增量索引,且不会损失性能
- 文档排名(使用 tf-idf,可选用户提供的权重)
- 字段加权
- 带有
AND
、OR
和NOT
运算符的复杂布尔查询 - 前缀匹配、模糊匹配和精确短语查询
- 支持 双音素语音匹配
- 自动完成建议(带有模糊前缀建议)
- 在 多种语言 中基于词干的查询扩展(使用 Snowball)
- 支持中文分词和查询(使用 Friso)
- 数值过滤器和范围
- 使用 Redis 地理空间索引进行地理空间搜索
- 强大的聚合引擎
- 支持所有
utf-8
编码的文本 - 检索完整文档、选定的字段或仅检索文档 ID
- 排序结果(例如,按创建日期)
客户端
由于 Redis
不仅仅是一个向量数据库,因此除了 LangChain
集成之外,通常还有需要使用 Redis
客户端的用例。您可以使用任何标准的 Redis
客户端库来运行搜索和查询命令,但最好使用包装了搜索和查询 API 的库。以下是一些示例,但您可以在此处找到更多客户端库。
项目 | 语言 | 许可证 | 作者 | 星星数 |
---|---|---|---|---|
jedis | Java | MIT | Redis | |
redisvl | Python | MIT | Redis | |
redis-py | Python | MIT | Redis | |
node-redis | Node.js | MIT | Redis | |
nredisstack | .NET | MIT | Redis |
部署选项
有多种方法可以使用 RediSearch 部署 Redis。最简单的入门方法是使用 Docker,但还有许多潜在的部署选项,例如
- Redis Cloud
- Docker (Redis Stack)
- 云市场:AWS Marketplace、Google Marketplace 或 Azure Marketplace
- 本地部署:Redis Enterprise Software
- Kubernetes:Kubernetes 上的 Redis Enterprise Software
Redis 连接 URL 方案
有效的 Redis URL 方案为
redis://
- 连接到 Redis 独立版,未加密rediss://
- 连接到 Redis 独立版,使用 TLS 加密redis+sentinel://
- 通过 Redis Sentinel 连接到 Redis 服务器,未加密rediss+sentinel://
- 通过 Redis Sentinel 连接到 Redis 服务器,所有连接均使用 TLS 加密
有关其他连接参数的更多信息,请参阅redis-py 文档。
设置
要使用 RedisVectorStore,您需要安装 langchain-redis
合作软件包,以及本笔记本中使用的其他软件包。
%pip install -qU langchain-redis langchain-huggingface sentence-transformers scikit-learn
Note: you may need to restart the kernel to use updated packages.
凭据
Redis 连接凭据作为 Redis 连接 URL 的一部分传递。Redis 连接 URL 用途广泛,可以适应各种 Redis 服务器拓扑结构和身份验证方法。这些 URL 遵循特定格式,其中包括连接协议、身份验证详细信息、主机、端口和数据库信息。Redis 连接 URL 的基本结构为
[protocol]://[auth]@[host]:[port]/[database]
其中
- 协议可以是用于标准连接的 redis,用于 SSL/TLS 连接的 rediss 或用于 Sentinel 连接的 redis+sentinel。
- auth 包括用户名和密码(如果适用)。
- host 是 Redis 服务器主机名或 IP 地址。
- port 是 Redis 服务器端口。
- database 是 Redis 数据库编号。
Redis 连接 URL 支持多种配置,包括
- 独立 Redis 服务器(带或不带身份验证)
- Redis Sentinel 设置
- SSL/TLS 加密连接
- 不同的身份验证方法(仅密码或用户名-密码)
以下是不同配置的 Redis 连接 URL 示例
# connection to redis standalone at localhost, db 0, no password
redis_url = "redis://127.0.0.1:6379"
# connection to host "redis" port 7379 with db 2 and password "secret" (old style authentication scheme without username / pre 6.x)
redis_url = "redis://:secret@redis:7379/2"
# connection to host redis on default port with user "joe", pass "secret" using redis version 6+ ACLs
redis_url = "redis://joe:secret@redis/0"
# connection to sentinel at localhost with default group mymaster and db 0, no password
redis_url = "redis+sentinel://127.0.0.1:26379"
# connection to sentinel at host redis with default port 26379 and user "joe" with password "secret" with default group mymaster and db 0
redis_url = "redis+sentinel://joe:secret@redis"
# connection to sentinel, no auth with sentinel monitoring group "zone-1" and database 2
redis_url = "redis+sentinel://redis:26379/zone-1/2"
# connection to redis standalone at localhost, db 0, no password but with TLS support
redis_url = "rediss://127.0.0.1:6379"
# connection to redis sentinel at localhost and default port, db 0, no password
# but with TLS support for booth Sentinel and Redis server
redis_url = "rediss+sentinel://127.0.0.1"
使用 Docker 启动 Redis 实例
要将 Redis 与 LangChain 一起使用,您需要一个正在运行的 Redis 实例。您可以使用 Docker 通过以下方式启动一个:
docker run -d -p 6379:6379 redis/redis-stack:latest
在此示例中,我们将使用本地 Redis 实例。如果您使用的是远程实例,则需要相应地修改 Redis URL。
import os
REDIS_URL = os.getenv("REDIS_URL", "redis://127.0.0.1:6379")
print(f"Connecting to Redis at: {REDIS_URL}")
Connecting to Redis at: redis://redis:6379
如果您想自动跟踪模型调用,还可以通过取消注释以下内容来设置您的LangSmith API 密钥
# os.environ["LANGSMITH_API_KEY"] = getpass.getpass("Enter your LangSmith API key: ")
# os.environ["LANGSMITH_TRACING"] = "true"
让我们通过 ping 它来检查 Redis 是否已启动并运行
import redis
redis_client = redis.from_url(REDIS_URL)
redis_client.ping()
True
示例数据
20 newsgroups 数据集包含大约 20 个主题的 18000 个新闻组帖子。我们将使用一个子集进行演示,并专注于两个类别:“alt.atheism” 和 “sci.space”
from langchain.docstore.document import Document
from sklearn.datasets import fetch_20newsgroups
categories = ["alt.atheism", "sci.space"]
newsgroups = fetch_20newsgroups(
subset="train", categories=categories, shuffle=True, random_state=42
)
# Use only the first 250 documents
texts = newsgroups.data[:250]
metadata = [
{"category": newsgroups.target_names[target]} for target in newsgroups.target[:250]
]
len(texts)
250
初始化
RedisVectorStore 实例可以通过多种方式初始化
RedisVectorStore.__init__
- 直接初始化RedisVectorStore.from_texts
- 从文本列表初始化(可选地带有元数据)RedisVectorStore.from_documents
- 从langchain_core.documents.Document
对象列表初始化RedisVectorStore.from_existing_index
- 从现有 Redis 索引初始化
下面我们将使用 RedisVectorStore.__init__
方法,使用 RedisConfig
实例。
pip install -qU langchain-openai
import getpass
import os
if not os.environ.get("OPENAI_API_KEY"):
os.environ["OPENAI_API_KEY"] = getpass.getpass("Enter API key for OpenAI: ")
from langchain_openai import OpenAIEmbeddings
embeddings = OpenAIEmbeddings(model="text-embedding-3-large")
我们将使用 SentenceTransformer 模型来创建嵌入。此模型在本地运行,不需要 API 密钥。
from langchain_redis import RedisConfig, RedisVectorStore
config = RedisConfig(
index_name="newsgroups",
redis_url=REDIS_URL,
metadata_schema=[
{"name": "category", "type": "tag"},
],
)
vector_store = RedisVectorStore(embeddings, config=config)
管理向量存储
向向量存储添加项
ids = vector_store.add_texts(texts, metadata)
print(ids[0:10])
['newsgroups:f1e788ee61fe410daa8ef941dd166223', 'newsgroups:80b39032181f4299a359a9aaed6e2401', 'newsgroups:99a3efc1883647afba53d115b49e6e92', 'newsgroups:503a6c07cd71418eb71e11b42589efd7', 'newsgroups:7351210e32d1427bbb3c7426cf93a44f', 'newsgroups:4e79fdf67abe471b8ee98ba0e8a1a055', 'newsgroups:03559a1d574e4f9ca0479d7b3891402e', 'newsgroups:9a1c2a7879b8409a805db72feac03580', 'newsgroups:3578a1e129f5435f9743cf803413f37a', 'newsgroups:9f68baf4d6b04f1683d6b871ce8ad92d']
让我们检查第一个文档
texts[0], metadata[0]
('From: [email protected] (Bill Conner)\nSubject: Re: Not the Omni!\nNntp-Posting-Host: okcforum.osrhe.edu\nOrganization: Okcforum Unix Users Group\nX-Newsreader: TIN [version 1.1 PL6]\nLines: 18\n\nCharley Wingate ([email protected]) wrote:\n: \n: >> Please enlighten me. How is omnipotence contradictory?\n: \n: >By definition, all that can occur in the universe is governed by the rules\n: >of nature. Thus god cannot break them. Anything that god does must be allowed\n: >in the rules somewhere. Therefore, omnipotence CANNOT exist! It contradicts\n: >the rules of nature.\n: \n: Obviously, an omnipotent god can change the rules.\n\nWhen you say, "By definition", what exactly is being defined;\ncertainly not omnipotence. You seem to be saying that the "rules of\nnature" are pre-existant somehow, that they not only define nature but\nactually cause it. If that\'s what you mean I\'d like to hear your\nfurther thoughts on the question.\n\nBill\n',
{'category': 'alt.atheism'})
从向量存储删除项
# Delete documents by passing one or more keys/ids
vector_store.index.drop_keys(ids[0])
1
检查创建的索引
一旦构造了 Redis
VectorStore 对象,如果 Redis 中尚不存在索引,则会在 Redis 中创建一个索引。可以使用 rvl
和 redis-cli
命令行工具检查该索引。如果您在上面安装了 redisvl
,则可以使用 rvl
命令行工具来检查索引。
# assumes you're running Redis locally (use --host, --port, --password, --username, to change this)
!rvl index listall --port 6379
[32m17:54:50[0m [34m[RedisVL][0m [1;30mINFO[0m Using Redis address from environment variable, REDIS_URL
[32m17:54:50[0m [34m[RedisVL][0m [1;30mINFO[0m Indices:
[32m17:54:50[0m [34m[RedisVL][0m [1;30mINFO[0m 1. newsgroups
Redis
VectorStore 实现将尝试为通过 from_texts
、from_texts_return_keys
和 from_documents
方法传递的任何元数据生成索引架构(用于筛选的字段)。这样,无论传递什么元数据,都将索引到 Redis 搜索索引中,从而允许对这些字段进行筛选。
下面我们展示了从上面定义的元数据中创建的字段
!rvl index info -i newsgroups --port 6379
[32m17:54:50[0m [34m[RedisVL][0m [1;30mINFO[0m Using Redis address from environment variable, REDIS_URL
Index Information:
╭──────────────┬────────────────┬────────────────┬─────────────────┬────────────╮
│ Index Name │ Storage Type │ Prefixes │ Index Options │ Indexing │
├──────────────┼────────────────┼────────────────┼─────────────────┼────────────┤
│ newsgroups │ HASH │ ['newsgroups'] │ [] │ 0 │
╰──────────────┴────────────────┴────────────────┴─────────────────┴────────────╯
Index Fields:
╭───────────┬─────────────┬────────┬────────────────┬────────────────┬────────────────┬────────────────┬────────────────┬────────────────┬─────────────────┬────────────────╮
│ Name │ Attribute │ Type │ Field Option │ Option Value │ Field Option │ Option Value │ Field Option │ Option Value │ Field Option │ Option Value │
├───────────┼─────────────┼────────┼────────────────┼────────────────┼────────────────┼────────────────┼────────────────┼────────────────┼─────────────────┼────────────────┤
│ text │ text │ TEXT │ WEIGHT │ 1 │ │ │ │ │ │ │
│ embedding │ embedding │ VECTOR │ algorithm │ FLAT │ data_type │ FLOAT32 │ dim │ 768 │ distance_metric │ COSINE │
│ category │ category │ TAG │ SEPARATOR │ | │ │ │ │ │ │ │
╰───────────┴─────────────┴────────┴────────────────┴────────────────┴────────────────┴────────────────┴────────────────┴────────────────┴─────────────────┴────────────────╯
!rvl stats -i newsgroups --port 6379
[32m17:54:51[0m [34m[RedisVL][0m [1;30mINFO[0m Using Redis address from environment variable, REDIS_URL
Statistics:
╭─────────────────────────────┬────────────╮
│ Stat Key │ Value │
├─────────────────────────────┼────────────┤
│ num_docs │ 249 │
│ num_terms │ 16178 │
│ max_doc_id │ 250 │
│ num_records │ 50394 │
│ percent_indexed │ 1 │
│ hash_indexing_failures │ 0 │
│ number_of_uses │ 2 │
│ bytes_per_record_avg │ 38.2743 │
│ doc_table_size_mb │ 0.0263586 │
│ inverted_sz_mb │ 1.83944 │
│ key_table_size_mb │ 0.00932026 │
│ offset_bits_per_record_avg │ 10.6699 │
│ offset_vectors_sz_mb │ 0.089057 │
│ offsets_per_term_avg │ 1.38937 │
│ records_per_doc_avg │ 202.386 │
│ sortable_values_size_mb │ 0 │
│ total_indexing_time │ 72.444 │
│ total_inverted_index_blocks │ 16207 │
│ vector_index_sz_mb │ 3.01776 │
╰─────────────────────────────┴────────────╯
查询向量存储
一旦创建了向量存储并添加了相关文档,您很可能希望在链或代理的运行期间查询它。
直接查询
可以按如下方式执行简单的相似性搜索
query = "Tell me about space exploration"
results = vector_store.similarity_search(query, k=2)
print("Simple Similarity Search Results:")
for doc in results:
print(f"Content: {doc.page_content[:100]}...")
print(f"Metadata: {doc.metadata}")
print()
Simple Similarity Search Results:
Content: From: [email protected] (Terry Ford)
Subject: A flawed propulsion system: Space Shuttle
X-Ad...
Metadata: {'category': 'sci.space'}
Content: From: [email protected]
Subject: Space Design Movies?
Article-I.D.: aurora.1993Apr23.124722.1
...
Metadata: {'category': 'sci.space'}
如果您想执行相似性搜索并接收相应的分数,可以运行
# Similarity search with score and filter
scored_results = vector_store.similarity_search_with_score(query, k=2)
print("Similarity Search with Score Results:")
for doc, score in scored_results:
print(f"Content: {doc.page_content[:100]}...")
print(f"Metadata: {doc.metadata}")
print(f"Score: {score}")
print()
Similarity Search with Score Results:
Content: From: [email protected] (Terry Ford)
Subject: A flawed propulsion system: Space Shuttle
X-Ad...
Metadata: {'category': 'sci.space'}
Score: 0.569670975208
Content: From: [email protected]
Subject: Space Design Movies?
Article-I.D.: aurora.1993Apr23.124722.1
...
Metadata: {'category': 'sci.space'}
Score: 0.590400338173
通过转换为检索器进行查询
您还可以将向量存储转换为检索器,以便在链中更轻松地使用。
retriever = vector_store.as_retriever(search_type="similarity", search_kwargs={"k": 2})
retriever.invoke("What planet in the solar system has the largest number of moons?")
[Document(metadata={'category': 'sci.space'}, page_content='Subject: Re: Comet in Temporary Orbit Around Jupiter?\nFrom: Robert Coe <[email protected]>\nDistribution: world\nOrganization: 1776 Enterprises, Sudbury MA\nLines: 23\n\[email protected] writes:\n\n> >> Also, perihelions of Gehrels3 were:\n> >> \n> >> April 1973 83 jupiter radii\n> >> August 1970 ~3 jupiter radii\n> > \n> > Where 1 Jupiter radius = 71,000 km = 44,000 mi = 0.0005 AU. So the\n> > 1970 figure seems unlikely to actually be anything but a perijove.\n> > Is that the case for the 1973 figure as well?\n> > -- \n> Sorry, _perijoves_...I\'m not used to talking this language.\n\nHmmmm.... The prefix "peri-" is Greek, not Latin, so it\'s usually used\nwith the Greek form of the name of the body being orbited. (That\'s why\nit\'s "perihelion" rather than "perisol", "perigee" rather than "periterr",\nand "pericynthion" rather than "perilune".) So for Jupiter I\'d expect it\nto be something like "perizeon".) :^)\n\n ___ _ - Bob\n /__) _ / / ) _ _\n(_/__) (_)_(_) (___(_)_(/_______________________________________ [email protected]\nRobert K. Coe ** 14 Churchill St, Sudbury, Massachusetts 01776 ** 508-443-3265\n'),
Document(metadata={'category': 'sci.space'}, page_content='From: [email protected] (Dillon Pyron)\nSubject: Re: Why not give $1 billion to first year-long moon residents?\nLines: 42\nNntp-Posting-Host: skndiv.dseg.ti.com\nReply-To: [email protected]\nOrganization: TI/DSEG VAX Support\n\n\nIn article <[email protected]>, [email protected] (Peter Schaefer) writes:\n>In article <[email protected]>, [email protected] writes:\n>|> In article <[email protected]>, [email protected] (Gene Wright) writes:\n>|> > With the continuin talk about the "End of the Space Age" and complaints \n>|> > by government over the large cost, why not try something I read about \n>|> > that might just work.\n>|> > \n>|> > Announce that a reward of $1 billion would go to the first corporation \n>|> > who successfully keeps at least 1 person alive on the moon for a year. \n>|> > Then you\'d see some of the inexpensive but not popular technologies begin \n>|> > to be developed. THere\'d be a different kind of space race then!\n>|> > \n>|> > --\n>|> > [email protected] (Gene Wright)\n>|> > theporch.raider.net 615/297-7951 The MacInteresteds of Nashville\n>|> ====\n>|> If that were true, I\'d go for it.. I have a few friends who we could pool our\n>|> resources and do it.. Maybe make it a prize kind of liek the "Solar Car Race"\n>|> in Australia..\n>|> Anybody game for a contest!\n>|> \n>|> ==\n>|> Michael Adams, [email protected] -- I\'m not high, just jacked\n>\n>\n>Oh gee, a billion dollars! That\'d be just about enough to cover the cost of the\n>feasability study! Happy, Happy, JOY! JOY!\n>\n\nFeasability study?? What a wimp!! While you are studying, others would be\ndoing. Too damn many engineers doing way too little engineering.\n\n"He who sits on his arse sits on his fortune" - Sir Richard Francis Burton\n--\nDillon Pyron | The opinions expressed are those of the\nTI/DSEG Lewisville VAX Support | sender unless otherwise stated.\n(214)462-3556 (when I\'m here) |\n(214)492-4656 (when I\'m home) |Texans: Vote NO on Robin Hood. We need\[email protected] |solutions, not gestures.\nPADI DM-54909 |\n\n')]
用于检索增强生成
有关如何使用此向量存储进行检索增强生成 (RAG) 的指南,请参阅以下部分
Redis 特定功能
Redis 为向量搜索提供了一些独特的功能
使用元数据过滤的相似性搜索
我们可以根据元数据过滤搜索结果
from redisvl.query.filter import Tag
query = "Tell me about space exploration"
# Create a RedisVL filter expression
filter_condition = Tag("category") == "sci.space"
filtered_results = vector_store.similarity_search(query, k=2, filter=filter_condition)
print("Filtered Similarity Search Results:")
for doc in filtered_results:
print(f"Content: {doc.page_content[:100]}...")
print(f"Metadata: {doc.metadata}")
print()
Filtered Similarity Search Results:
Content: From: [email protected] (Terry Ford)
Subject: A flawed propulsion system: Space Shuttle
X-Ad...
Metadata: {'category': 'sci.space'}
Content: From: [email protected]
Subject: Space Design Movies?
Article-I.D.: aurora.1993Apr23.124722.1
...
Metadata: {'category': 'sci.space'}
最大边际相关性搜索
最大边际相关性搜索有助于获得多样化的结果
# Maximum marginal relevance search with filter
mmr_results = vector_store.max_marginal_relevance_search(
query, k=2, fetch_k=10, filter=filter_condition
)
print("Maximum Marginal Relevance Search Results:")
for doc in mmr_results:
print(f"Content: {doc.page_content[:100]}...")
print(f"Metadata: {doc.metadata}")
print()
Maximum Marginal Relevance Search Results:
Content: From: [email protected] (Terry Ford)
Subject: A flawed propulsion system: Space Shuttle
X-Ad...
Metadata: {'category': 'sci.space'}
Content: From: [email protected] (Michael Moroney)
Subject: Re: Vulcan? (No, not the guy with the ears!)
...
Metadata: {'category': 'sci.space'}
链的使用
以下代码展示了如何在简单的 RAG 链中使用向量存储作为检索器
pip install -qU langchain-openai
import getpass
import os
if not os.environ.get("OPENAI_API_KEY"):
os.environ["OPENAI_API_KEY"] = getpass.getpass("Enter API key for OpenAI: ")
from langchain_openai import ChatOpenAI
llm = ChatOpenAI(model="gpt-4o-mini")
from langchain_core.output_parsers import StrOutputParser
from langchain_core.prompts import ChatPromptTemplate
from langchain_core.runnables import RunnablePassthrough
# Prompt
prompt = ChatPromptTemplate.from_messages(
[
(
"human",
"""You are an assistant for question-answering tasks. Use the following pieces of retrieved context to answer the question. If you don't know the answer, just say that you don't know. Use three sentences maximum and keep the answer concise.
Question: {question}
Context: {context}
Answer:""",
),
]
)
def format_docs(docs):
return "\n\n".join(doc.page_content for doc in docs)
rag_chain = (
{"context": retriever | format_docs, "question": RunnablePassthrough()}
| prompt
| llm
| StrOutputParser()
)
rag_chain.invoke("Describe the Space Shuttle program?")
'The Space Shuttle program was a NASA initiative that enabled reusable spacecraft to transport astronauts and cargo to and from low Earth orbit. It conducted a variety of missions, including satellite deployment, scientific research, and assembly of the International Space Station, and typically carried a crew of five astronauts. Although it achieved many successes, the program faced criticism for its safety concerns and the complexity of its propulsion system.'
连接到现有索引
为了在使用 Redis
VectorStore 时索引相同的元数据。你需要传入相同的 index_schema
,可以是 YAML 文件的路径,也可以是字典。以下展示了如何从索引获取 schema 并连接到现有索引。
# write the schema to a yaml file
vector_store.index.schema.to_yaml("redis_schema.yaml")
# now we can connect to our existing index as follows
new_rdvs = RedisVectorStore(
embeddings,
redis_url=REDIS_URL,
schema_path="redis_schema.yaml",
)
results = new_rdvs.similarity_search("Space Shuttle Propulsion System", k=3)
print(results[0])
18:19:58 redisvl.index.index INFO Index already exists, not overwriting.
page_content='From: [email protected] (Terry Ford)
Subject: A flawed propulsion system: Space Shuttle
X-Added: Forwarded by Space Digest
Organization: [via International Space University]
Original-Sender: [email protected]
Distribution: sci
Lines: 13
For an essay, I am writing about the space shuttle and a need for a better
propulsion system. Through research, I have found that it is rather clumsy
(i.e. all the checks/tests before launch), the safety hazards ("sitting
on a hydrogen bomb"), etc.. If you have any beefs about the current
space shuttle program Re: propulsion, please send me your ideas.
Thanks a lot.
--
Terry Ford [[email protected]]
Nepean, Ontario, Canada.
' metadata={'category': 'sci.space'}
# compare the two schemas to verify they are the same
new_rdvs.index.schema == vector_store.index.schema
True
清理向量存储
# Clear vector store
vector_store.index.delete(drop=True)
API 参考
有关所有 RedisVectorStore 功能和配置的详细文档,请访问 API 参考:https://python.langchain.ac.cn/api_reference/redis/vectorstores/langchain_redis.vectorstores.RedisVectorStore.html