anything-llm/server/utils/vectorDbProviders/lance/index.js
2024-08-19 14:07:07 -07:00

378 lines
12 KiB
JavaScript

const lancedb = require("@lancedb/lancedb");
const { toChunks, getEmbeddingEngineSelection } = require("../../helpers");
const { TextSplitter } = require("../../TextSplitter");
const { SystemSettings } = require("../../../models/systemSettings");
const { storeVectorResult, cachedVectorInformation } = require("../../files");
const { v4: uuidv4 } = require("uuid");
const { sourceIdentifier } = require("../../chats");
/**
* LancedDB Client connection object
* @typedef {import('@lancedb/lancedb').Connection} LanceClient
*/
const LanceDb = {
uri: `${!!process.env.STORAGE_DIR ? `${process.env.STORAGE_DIR}/` : "./storage/"
}lancedb`,
name: "LanceDb",
/** @returns {Promise<{client: LanceClient}>} */
connect: async function () {
if (process.env.VECTOR_DB !== "lancedb")
throw new Error("LanceDB::Invalid ENV settings");
const client = await lancedb.connect(this.uri);
return { client };
},
distanceToSimilarity: function (distance = null) {
if (distance === null || typeof distance !== "number") return 0.0;
if (distance >= 1.0) return 1;
if (distance <= 0) return 0;
return 1 - distance;
},
heartbeat: async function () {
await this.connect();
return { heartbeat: Number(new Date()) };
},
tables: async function () {
const { client } = await this.connect();
return await client.tableNames();
},
totalVectors: async function () {
const { client } = await this.connect();
const tables = await client.tableNames();
let count = 0;
for (const tableName of tables) {
const table = await client.openTable(tableName);
count += await table.countRows();
}
return count;
},
namespaceCount: async function (_namespace = null) {
const { client } = await this.connect();
const exists = await this.namespaceExists(client, _namespace);
if (!exists) return 0;
const table = await client.openTable(_namespace);
return (await table.countRows()) || 0;
},
/**
* Performs a SimilaritySearch on a give LanceDB namespace.
* @param {LanceClient} client
* @param {string} namespace
* @param {number[]} queryVector
* @param {number} similarityThreshold
* @param {number} topN
* @param {string[]} filterIdentifiers
* @returns
*/
similarityResponse: async function (
client,
namespace,
queryVector,
similarityThreshold = 0.25,
topN = 4,
filterIdentifiers = []
) {
const collection = await client.openTable(namespace);
const result = {
contextTexts: [],
sourceDocuments: [],
scores: [],
};
const response = await collection
.vectorSearch(queryVector)
.distanceType("cosine")
.limit(topN)
.toArray();
response.forEach((item) => {
if (this.distanceToSimilarity(item.score) < similarityThreshold) return;
const { vector: _, ...rest } = item;
if (filterIdentifiers.includes(sourceIdentifier(rest))) {
console.log(
"LanceDB: A source was filtered from context as it's parent document is pinned."
);
return;
}
result.contextTexts.push(rest.text);
result.sourceDocuments.push(rest);
result.scores.push(this.distanceToSimilarity(item.score));
});
return result;
},
/**
*
* @param {LanceClient} client
* @param {string} namespace
* @returns
*/
namespace: async function (client, namespace = null) {
if (!namespace) throw new Error("No namespace value provided.");
const collection = await client.openTable(namespace).catch(() => false);
if (!collection) return null;
return {
...collection,
};
},
/**
*
* @param {LanceClient} client
* @param {number[]} data
* @param {string} namespace
* @returns
*/
updateOrCreateCollection: async function (client, data = [], namespace) {
const hasNamespace = await this.hasNamespace(namespace);
if (hasNamespace) {
const collection = await client.openTable(namespace);
await collection.add(data);
return true;
}
await client.createTable(namespace, data);
return true;
},
hasNamespace: async function (namespace = null) {
if (!namespace) return false;
const { client } = await this.connect();
const exists = await this.namespaceExists(client, namespace);
return exists;
},
/**
*
* @param {LanceClient} client
* @param {string} namespace
* @returns
*/
namespaceExists: async function (client, namespace = null) {
if (!namespace) throw new Error("No namespace value provided.");
const collections = await client.tableNames();
return collections.includes(namespace);
},
/**
*
* @param {LanceClient} client
* @param {string} namespace
* @returns
*/
deleteVectorsInNamespace: async function (client, namespace = null) {
await client.dropTable(namespace);
return true;
},
deleteDocumentFromNamespace: async function (namespace, docId) {
const { client } = await this.connect();
const exists = await this.namespaceExists(client, namespace);
if (!exists) {
console.error(
`LanceDB:deleteDocumentFromNamespace - namespace ${namespace} does not exist.`
);
return;
}
const { DocumentVectors } = require("../../../models/vectors");
const table = await client.openTable(namespace);
const vectorIds = (await DocumentVectors.where({ docId })).map(
(record) => record.vectorId
);
if (vectorIds.length === 0) return;
await table.delete(`id IN (${vectorIds.map((v) => `'${v}'`).join(",")})`);
return true;
},
addDocumentToNamespace: async function (
namespace,
documentData = {},
fullFilePath = null,
skipCache = false
) {
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);
if (!skipCache) {
const cacheResult = await cachedVectorInformation(fullFilePath);
if (cacheResult.exists) {
const { client } = await this.connect();
const { chunks } = cacheResult;
const documentVectors = [];
const submissions = [];
for (const chunk of chunks) {
chunk.forEach((chunk) => {
const id = uuidv4();
const { id: _id, ...metadata } = chunk.metadata;
documentVectors.push({ docId, vectorId: id });
submissions.push({ id: id, vector: chunk.values, ...metadata });
});
}
await this.updateOrCreateCollection(client, submissions, namespace);
await DocumentVectors.bulkInsert(documentVectors);
return { vectorized: true, error: null };
}
}
// 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 `xyz.fromDocuments`
// because we then cannot atomically control our namespace to granularly find/remove documents
// from vectordb.
const EmbedderEngine = getEmbeddingEngineSelection();
const textSplitter = new TextSplitter({
chunkSize: TextSplitter.determineMaxChunkSize(
await SystemSettings.getValueOrFallback({
label: "text_splitter_chunk_size",
}),
EmbedderEngine?.embeddingMaxChunkLength
),
chunkOverlap: await SystemSettings.getValueOrFallback(
{ label: "text_splitter_chunk_overlap" },
20
),
chunkHeaderMeta: {
sourceDocument: metadata?.title,
published: metadata?.published || "unknown",
},
});
const textChunks = await textSplitter.splitText(pageContent);
console.log("Chunks created from document:", textChunks.length);
const documentVectors = [];
const vectors = [];
const submissions = [];
const vectorValues = await EmbedderEngine.embedChunks(textChunks);
if (!!vectorValues && vectorValues.length > 0) {
for (const [i, vector] of vectorValues.entries()) {
const vectorRecord = {
id: uuidv4(),
values: vector,
// [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: textChunks[i] },
};
vectors.push(vectorRecord);
submissions.push({
...vectorRecord.metadata,
id: vectorRecord.id,
vector: vectorRecord.values,
});
documentVectors.push({ docId, vectorId: vectorRecord.id });
}
} else {
throw new Error(
"Could not embed document chunks! This document will not be recorded."
);
}
if (vectors.length > 0) {
const chunks = [];
for (const chunk of toChunks(vectors, 500)) chunks.push(chunk);
console.log("Inserting vectorized chunks into LanceDB collection.");
const { client } = await this.connect();
await this.updateOrCreateCollection(client, submissions, namespace);
await storeVectorResult(chunks, fullFilePath);
}
await DocumentVectors.bulkInsert(documentVectors);
return { vectorized: true, error: null };
} catch (e) {
console.error("addDocumentToNamespace", e.message);
return { vectorized: false, error: e.message };
}
},
performSimilaritySearch: async function ({
namespace = null,
input = "",
LLMConnector = null,
similarityThreshold = 0.25,
topN = 4,
filterIdentifiers = [],
}) {
if (!namespace || !input || !LLMConnector)
throw new Error("Invalid request to performSimilaritySearch.");
const { client } = await this.connect();
if (!(await this.namespaceExists(client, namespace))) {
return {
contextTexts: [],
sources: [],
message: "Invalid query - no documents found for workspace!",
};
}
const queryVector = await LLMConnector.embedTextInput(input);
const { contextTexts, sourceDocuments } = await this.similarityResponse(
client,
namespace,
queryVector,
similarityThreshold,
topN,
filterIdentifiers
);
const sources = sourceDocuments.map((metadata, i) => {
return { metadata: { ...metadata, text: contextTexts[i] } };
});
return {
contextTexts,
sources: this.curateSources(sources),
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.");
await this.deleteVectorsInNamespace(client, namespace);
return {
message: `Namespace ${namespace} was deleted.`,
};
},
reset: async function () {
const { client } = await this.connect();
const fs = require("fs");
fs.rm(`${client.uri}`, { recursive: true }, () => null);
return { reset: true };
},
curateSources: function (sources = []) {
const documents = [];
for (const source of sources) {
const { text, vector: _v, score: _s, ...rest } = source;
const metadata = rest.hasOwnProperty("metadata") ? rest.metadata : rest;
if (Object.keys(metadata).length > 0) {
documents.push({
...metadata,
...(text ? { text } : {}),
});
}
}
return documents;
},
};
module.exports.LanceDb = LanceDb;