agsamantha/node_modules/@langchain/community/dist/document_loaders/web/puppeteer.cjs
2024-10-02 15:15:21 -05:00

132 lines
4.8 KiB
JavaScript

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.PuppeteerWebBaseLoader = void 0;
const documents_1 = require("@langchain/core/documents");
const base_1 = require("@langchain/core/document_loaders/base");
/**
* Class that extends the BaseDocumentLoader class and implements the
* DocumentLoader interface. It represents a document loader for scraping
* web pages using Puppeteer.
* @example
* ```typescript
* const loader = new PuppeteerWebBaseLoader("https:exampleurl.com", {
* launchOptions: {
* headless: true,
* },
* gotoOptions: {
* waitUntil: "domcontentloaded",
* },
* });
* const screenshot = await loader.screenshot();
* ```
*/
class PuppeteerWebBaseLoader extends base_1.BaseDocumentLoader {
constructor(webPath, options) {
super();
Object.defineProperty(this, "webPath", {
enumerable: true,
configurable: true,
writable: true,
value: webPath
});
Object.defineProperty(this, "options", {
enumerable: true,
configurable: true,
writable: true,
value: void 0
});
this.options = options ?? undefined;
}
static async _scrape(url, options) {
const { launch } = await PuppeteerWebBaseLoader.imports();
const browser = await launch({
headless: true,
defaultViewport: null,
ignoreDefaultArgs: ["--disable-extensions"],
...options?.launchOptions,
});
const page = await browser.newPage();
await page.goto(url, {
timeout: 180000,
waitUntil: "domcontentloaded",
...options?.gotoOptions,
});
const bodyHTML = options?.evaluate
? await options?.evaluate(page, browser)
: await page.evaluate(() => document.body.innerHTML);
await browser.close();
return bodyHTML;
}
/**
* Method that calls the _scrape method to perform the scraping of the web
* page specified by the webPath property.
* @returns Promise that resolves to the scraped HTML content of the web page.
*/
async scrape() {
return PuppeteerWebBaseLoader._scrape(this.webPath, this.options);
}
/**
* Method that calls the scrape method and returns the scraped HTML
* content as a Document object.
* @returns Promise that resolves to an array of Document objects.
*/
async load() {
const text = await this.scrape();
const metadata = { source: this.webPath };
return [new documents_1.Document({ pageContent: text, metadata })];
}
/**
* Static class method used to screenshot a web page and return
* it as a {@link Document} object where the pageContent property
* is the screenshot encoded in base64.
*
* @param {string} url
* @param {PuppeteerWebBaseLoaderOptions} options
* @returns {Document} A document object containing the screenshot of the page encoded in base64.
*/
static async _screenshot(url, options) {
const { launch } = await PuppeteerWebBaseLoader.imports();
const browser = await launch({
headless: true,
defaultViewport: null,
ignoreDefaultArgs: ["--disable-extensions"],
...options?.launchOptions,
});
const page = await browser.newPage();
await page.goto(url, {
timeout: 180000,
waitUntil: "domcontentloaded",
...options?.gotoOptions,
});
const screenshot = await page.screenshot();
const base64 = screenshot.toString("base64");
const metadata = { source: url };
return new documents_1.Document({ pageContent: base64, metadata });
}
/**
* Screenshot a web page and return it as a {@link Document} object where
* the pageContent property is the screenshot encoded in base64.
*
* @returns {Promise<Document>} A document object containing the screenshot of the page encoded in base64.
*/
async screenshot() {
return PuppeteerWebBaseLoader._screenshot(this.webPath, this.options);
}
/**
* Static method that imports the necessary Puppeteer modules. It returns
* a Promise that resolves to an object containing the imported modules.
* @returns Promise that resolves to an object containing the imported Puppeteer modules.
*/
static async imports() {
try {
// eslint-disable-next-line import/no-extraneous-dependencies
const { launch } = await import("puppeteer");
return { launch };
}
catch (e) {
console.error(e);
throw new Error("Please install puppeteer as a dependency with, e.g. `yarn add puppeteer`");
}
}
}
exports.PuppeteerWebBaseLoader = PuppeteerWebBaseLoader;