anything-llm/server/utils/vectorDbProviders/chroma/index.js
2023-06-08 18:58:26 -07:00

316 lines
11 KiB
JavaScript

const { ChromaClient, OpenAIEmbeddingFunction } = require("chromadb");
const { Chroma: ChromaStore } = require("langchain/vectorstores/chroma");
const { OpenAI } = require("langchain/llms/openai");
const { ChatOpenAI } = require("langchain/chat_models/openai");
const { VectorDBQAChain } = require("langchain/chains");
const { OpenAIEmbeddings } = require("langchain/embeddings/openai");
const { RecursiveCharacterTextSplitter } = require("langchain/text_splitter");
const { storeVectorResult, cachedVectorInformation } = require("../../files");
const { Configuration, OpenAIApi } = require("openai");
const { v4: uuidv4 } = require("uuid");
const { toChunks, curateSources } = require("../../helpers");
const Chroma = {
name: "Chroma",
connect: async function () {
if (process.env.VECTOR_DB !== "chroma")
throw new Error("Chroma::Invalid ENV settings");
const client = new ChromaClient({
path: process.env.CHROMA_ENDPOINT, // if not set will fallback to localhost:8000
});
const isAlive = await client.heartbeat();
if (!isAlive)
throw new Error(
"ChromaDB::Invalid Heartbeat received - is the instance online?"
);
return { client };
},
heartbeat: async function () {
const { client } = await this.connect();
return { heartbeat: await client.heartbeat() };
},
totalIndicies: async function () {
const { client } = await this.connect();
const collections = await client.listCollections();
var totalVectors = 0;
for (const collectionObj of collections) {
const collection = await client
.getCollection({ name: collectionObj.name })
.catch(() => null);
if (!collection) continue;
totalVectors += await collection.count();
}
return totalVectors;
},
embeddingFunc: function () {
return new OpenAIEmbeddingFunction({
openai_api_key: process.env.OPEN_AI_KEY,
});
},
embedder: function () {
return new OpenAIEmbeddings({ openAIApiKey: process.env.OPEN_AI_KEY });
},
openai: function () {
const config = new Configuration({ apiKey: process.env.OPEN_AI_KEY });
const openai = new OpenAIApi(config);
return openai;
},
llm: function () {
const model = process.env.OPEN_MODEL_PREF || "gpt-3.5-turbo";
return new OpenAI({
openAIApiKey: process.env.OPEN_AI_KEY,
temperature: 0.7,
modelName: model,
});
},
embedChunk: async function (openai, textChunk) {
const {
data: { data },
} = await openai.createEmbedding({
model: "text-embedding-ada-002",
input: textChunk,
});
return data.length > 0 && data[0].hasOwnProperty("embedding")
? data[0].embedding
: null;
},
namespace: async function (client, namespace = null) {
if (!namespace) throw new Error("No namespace value provided.");
const collection = await client
.getCollection({ name: namespace })
.catch(() => null);
if (!collection) return null;
return {
...collection,
vectorCount: await collection.count(),
};
},
hasNamespace: async function (namespace = null) {
if (!namespace) return false;
const { client } = await this.connect();
return await this.namespaceExists(client, namespace);
},
namespaceExists: async function (client, namespace = null) {
if (!namespace) throw new Error("No namespace value provided.");
const collection = await client
.getCollection({ name: namespace })
.catch((e) => {
console.error("ChromaDB::namespaceExists", e.message);
return null;
});
return !!collection;
},
deleteVectorsInNamespace: async function (client, namespace = null) {
await client.deleteCollection({ name: namespace });
return true;
},
addDocumentToNamespace: async function (
namespace,
documentData = {},
fullFilePath = null
) {
const { DocumentVectors } = require("../../../models/vectors");
try {
const { pageContent, docId, ...metadata } = documentData;
if (!pageContent || pageContent.length == 0) return false;
console.log("Adding new vectorized document into namespace", namespace);
const cacheResult = await cachedVectorInformation(fullFilePath);
if (cacheResult.exists) {
const { client } = await this.connect();
const collection = await client.getOrCreateCollection({
name: namespace,
metadata: { "hnsw:space": "cosine" },
embeddingFunction: this.embeddingFunc(),
});
const { chunks } = cacheResult;
const documentVectors = [];
for (const chunk of chunks) {
const submission = {
ids: [],
embeddings: [],
metadatas: [],
documents: [],
};
// Before sending to Chroma and saving the records to our db
// we need to assign the id of each chunk that is stored in the cached file.
chunk.forEach((chunk) => {
const id = uuidv4();
const { id: _id, ...metadata } = chunk.metadata;
documentVectors.push({ docId, vectorId: id });
submission.ids.push(id);
submission.embeddings.push(chunk.values);
submission.metadatas.push(metadata);
submission.documents.push(metadata.text);
});
const additionResult = await collection.add(submission);
if (!additionResult)
throw new Error("Error embedding into ChromaDB", additionResult);
}
await DocumentVectors.bulkInsert(documentVectors);
return true;
}
// If we are here then we are going to embed and store a novel document.
// We have to do this manually as opposed to using LangChains `Chroma.fromDocuments`
// because we then cannot atomically control our namespace to granularly find/remove documents
// from vectordb.
const textSplitter = new RecursiveCharacterTextSplitter({
chunkSize: 1000,
chunkOverlap: 20,
});
const textChunks = await textSplitter.splitText(pageContent);
console.log("Chunks created from document:", textChunks.length);
const documentVectors = [];
const vectors = [];
const openai = this.openai();
const submission = {
ids: [],
embeddings: [],
metadatas: [],
documents: [],
};
for (const textChunk of textChunks) {
const vectorValues = await this.embedChunk(openai, textChunk);
if (!!vectorValues) {
const vectorRecord = {
id: uuidv4(),
values: vectorValues,
// [DO NOT REMOVE]
// LangChain will be unable to find your text if you embed manually and dont include the `text` key.
// https://github.com/hwchase17/langchainjs/blob/2def486af734c0ca87285a48f1a04c057ab74bdf/langchain/src/vectorstores/pinecone.ts#L64
metadata: { ...metadata, text: textChunk },
};
submission.ids.push(vectorRecord.id);
submission.embeddings.push(vectorRecord.values);
submission.metadatas.push(metadata);
submission.documents.push(textChunk);
vectors.push(vectorRecord);
documentVectors.push({ docId, vectorId: vectorRecord.id });
} else {
console.error(
"Could not use OpenAI to embed document chunk! This document will not be recorded."
);
}
}
const { client } = await this.connect();
const collection = await client.getOrCreateCollection({
name: namespace,
metadata: { "hnsw:space": "cosine" },
embeddingFunction: this.embeddingFunc(),
});
if (vectors.length > 0) {
const chunks = [];
console.log("Inserting vectorized chunks into Chroma collection.");
for (const chunk of toChunks(vectors, 500)) chunks.push(chunk);
const additionResult = await collection.add(submission);
if (!additionResult)
throw new Error("Error embedding into ChromaDB", additionResult);
await storeVectorResult(chunks, fullFilePath);
}
await DocumentVectors.bulkInsert(documentVectors);
return true;
} catch (e) {
console.error("addDocumentToNamespace", e.message);
return false;
}
},
deleteDocumentFromNamespace: async function (namespace, docId) {
const { DocumentVectors } = require("../../../models/vectors");
const { client } = await this.connect();
if (!(await this.namespaceExists(client, namespace))) return;
const collection = await client.getCollection({
name: namespace,
embeddingFunction: this.embeddingFunc(),
});
const knownDocuments = await DocumentVectors.where(`docId = '${docId}'`);
if (knownDocuments.length === 0) return;
const vectorIds = knownDocuments.map((doc) => doc.vectorId);
await collection.delete({ ids: vectorIds });
const indexes = knownDocuments.map((doc) => doc.id);
await DocumentVectors.deleteIds(indexes);
return true;
},
query: async function (reqBody = {}) {
const { namespace = null, input } = reqBody;
if (!namespace || !input) throw new Error("Invalid request body");
const { client } = await this.connect();
if (!(await this.namespaceExists(client, namespace))) {
return {
response: null,
sources: [],
message: "Invalid query - no documents found for workspace!",
};
}
const vectorStore = await ChromaStore.fromExistingCollection(
this.embedder(),
{ collectionName: namespace, url: process.env.CHROMA_ENDPOINT }
);
const model = this.llm();
const chain = VectorDBQAChain.fromLLM(model, vectorStore, {
k: 5,
returnSourceDocuments: true,
});
const response = await chain.call({ query: input });
return {
response: response.text,
sources: curateSources(response.sourceDocuments),
message: false,
};
},
"namespace-stats": async function (reqBody = {}) {
const { namespace = null } = reqBody;
if (!namespace) throw new Error("namespace required");
const { client } = await this.connect();
if (!(await this.namespaceExists(client, namespace)))
throw new Error("Namespace by that name does not exist.");
const stats = await this.namespace(client, namespace);
return stats
? stats
: { message: "No stats were able to be fetched from DB for namespace" };
},
"delete-namespace": async function (reqBody = {}) {
const { namespace = null } = reqBody;
const { client } = await this.connect();
if (!(await this.namespaceExists(client, namespace)))
throw new Error("Namespace by that name does not exist.");
const details = await this.namespace(client, namespace);
await this.deleteVectorsInNamespace(client, namespace);
return {
message: `Namespace ${namespace} was deleted along with ${details?.vectorCount} vectors.`,
};
},
reset: async function () {
const { client } = await this.connect();
await client.reset();
return { reset: true };
},
};
module.exports.Chroma = Chroma;