langchain/templates/rag-supabase/README.md

133 lines
4.2 KiB
Markdown

# rag_supabase
This template performs RAG with Supabase.
[Supabase](https://supabase.com/docs) is an open-source Firebase alternative. It is built on top of [PostgreSQL](https://en.wikipedia.org/wiki/PostgreSQL), a free and open-source relational database management system (RDBMS) and uses [pgvector](https://github.com/pgvector/pgvector) to store embeddings within your tables.
## Environment Setup
Set the `OPENAI_API_KEY` environment variable to access the OpenAI models.
To get your `OPENAI_API_KEY`, navigate to [API keys](https://platform.openai.com/account/api-keys) on your OpenAI account and create a new secret key.
To find your `SUPABASE_URL` and `SUPABASE_SERVICE_KEY`, head to your Supabase project's [API settings](https://supabase.com/dashboard/project/_/settings/api).
- `SUPABASE_URL` corresponds to the Project URL
- `SUPABASE_SERVICE_KEY` corresponds to the `service_role` API key
```shell
export SUPABASE_URL=
export SUPABASE_SERVICE_KEY=
export OPENAI_API_KEY=
```
## Setup Supabase Database
Use these steps to setup your Supabase database if you haven't already.
1. Head over to https://database.new to provision your Supabase database.
2. In the studio, jump to the [SQL editor](https://supabase.com/dashboard/project/_/sql/new) and run the following script to enable `pgvector` and setup your database as a vector store:
```sql
-- Enable the pgvector extension to work with embedding vectors
create extension if not exists vector;
-- Create a table to store your documents
create table
documents (
id uuid primary key,
content text, -- corresponds to Document.pageContent
metadata jsonb, -- corresponds to Document.metadata
embedding vector (1536) -- 1536 works for OpenAI embeddings, change as needed
);
-- Create a function to search for documents
create function match_documents (
query_embedding vector (1536),
filter jsonb default '{}'
) returns table (
id uuid,
content text,
metadata jsonb,
similarity float
) language plpgsql as $$
#variable_conflict use_column
begin
return query
select
id,
content,
metadata,
1 - (documents.embedding <=> query_embedding) as similarity
from documents
where metadata @> filter
order by documents.embedding <=> query_embedding;
end;
$$;
```
## Setup Environment Variables
Since we are using [`SupabaseVectorStore`](https://python.langchain.com/docs/integrations/vectorstores/supabase) and [`OpenAIEmbeddings`](https://python.langchain.com/docs/integrations/text_embedding/openai), we need to load their API keys.
## Usage
First, install the LangChain CLI:
```shell
pip install -U langchain-cli
```
To create a new LangChain project and install this as the only package, you can do:
```shell
langchain app new my-app --package rag-supabase
```
If you want to add this to an existing project, you can just run:
```shell
langchain app add rag-supabase
```
And add the following code to your `server.py` file:
```python
from rag_supabase.chain import chain as rag_supabase_chain
add_routes(app, rag_supabase_chain, path="/rag-supabase")
```
(Optional) Let's now configure LangSmith.
LangSmith will help us trace, monitor and debug LangChain applications.
You can sign up for LangSmith [here](https://smith.langchain.com/).
If you don't have access, you can skip this section
```shell
export LANGCHAIN_TRACING_V2=true
export LANGCHAIN_API_KEY=<your-api-key>
export LANGCHAIN_PROJECT=<your-project> # if not specified, defaults to "default"
```
If you are inside this directory, then you can spin up a LangServe instance directly by:
```shell
langchain serve
```
This will start the FastAPI app with a server is running locally at
[http://localhost:8000](http://localhost:8000)
We can see all templates at [http://127.0.0.1:8000/docs](http://127.0.0.1:8000/docs)
We can access the playground at [http://127.0.0.1:8000/rag-supabase/playground](http://127.0.0.1:8000/rag-supabase/playground)
We can access the template from code with:
```python
from langserve.client import RemoteRunnable
runnable = RemoteRunnable("http://localhost:8000/rag-supabase")
```
TODO: Add details about setting up the Supabase database