agsamantha/node_modules/@langchain/community/dist/embeddings/jina.js

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2024-10-02 15:15:21 -05:00
import { existsSync, readFileSync } from "fs";
import { parse } from "url";
import { Embeddings } from "@langchain/core/embeddings";
import { getEnvironmentVariable } from "@langchain/core/utils/env";
/**
* The default Jina API URL for embedding requests.
*/
const JINA_API_URL = "https://api.jina.ai/v1/embeddings";
/**
* Check if a URL is a local file.
* @param url - The URL to check.
* @returns True if the URL is a local file, False otherwise.
*/
function isLocal(url) {
const urlParsed = parse(url);
if (urlParsed.protocol === null || urlParsed.protocol === "file:") {
return existsSync(urlParsed.pathname || "");
}
return false;
}
/**
* Get the bytes string of a file.
* @param filePath - The path to the file.
* @returns The bytes string of the file.
*/
function getBytesStr(filePath) {
const imageFile = readFileSync(filePath);
return Buffer.from(imageFile).toString("base64");
}
/**
* A class for generating embeddings using the Jina API.
* @example
* ```typescript
* // Embed a query using the JinaEmbeddings class
* const model = new JinaEmbeddings();
* const res = await model.embedQuery(
* "What would be a good name for a semantic search engine ?",
* );
* console.log({ res });
* ```
*/
export class JinaEmbeddings extends Embeddings {
/**
* Constructor for the JinaEmbeddings class.
* @param fields - An optional object with properties to configure the instance.
*/
constructor(fields) {
const fieldsWithDefaults = {
model: "jina-embeddings-v2-base-en",
...fields,
};
super(fieldsWithDefaults);
Object.defineProperty(this, "apiKey", {
enumerable: true,
configurable: true,
writable: true,
value: void 0
});
Object.defineProperty(this, "model", {
enumerable: true,
configurable: true,
writable: true,
value: void 0
});
const apiKey = fieldsWithDefaults?.apiKey ||
getEnvironmentVariable("JINA_API_KEY") ||
getEnvironmentVariable("JINA_AUTH_TOKEN");
if (!apiKey) {
throw new Error("Jina API key not found");
}
this.model = fieldsWithDefaults?.model ?? this.model;
this.apiKey = apiKey;
}
/**
* Generates embeddings for an array of inputs.
* @param input - An array of strings or objects to generate embeddings for.
* @returns A Promise that resolves to an array of embeddings.
*/
// eslint-disable-next-line @typescript-eslint/no-explicit-any
async _embed(input) {
const response = await fetch(JINA_API_URL, {
method: "POST",
headers: {
Authorization: `Bearer ${this.apiKey}`,
"Content-Type": "application/json",
},
body: JSON.stringify({ input, model: this.model }),
});
const json = (await response.json());
if (!json.data) {
throw new Error(json.detail || "Unknown error from Jina API");
}
const sortedEmbeddings = json.data.sort((a, b) => a.index - b.index);
return sortedEmbeddings.map((item) => item.embedding);
}
/**
* Generates embeddings for an array of texts.
* @param texts - An array of strings to generate embeddings for.
* @returns A Promise that resolves to an array of embeddings.
*/
async embedDocuments(texts) {
return this._embed(texts);
}
/**
* Generates an embedding for a single text.
* @param text - A string to generate an embedding for.
* @returns A Promise that resolves to an array of numbers representing the embedding.
*/
async embedQuery(text) {
const embeddings = await this._embed([text]);
return embeddings[0];
}
/**
* Generates embeddings for an array of image URIs.
* @param uris - An array of image URIs to generate embeddings for.
* @returns A Promise that resolves to an array of embeddings.
*/
async embedImages(uris) {
const input = uris.map((uri) => (isLocal(uri) ? getBytesStr(uri) : uri));
return this._embed(input);
}
}