chtech-anythingllm/server/utils/agentFlows/executors/web-scraping.js

const { CollectorApi } = require("../../collectorApi");
const { TokenManager } = require("../../helpers/tiktoken");
const Provider = require("../../agents/aibitat/providers/ai-provider");
const { summarizeContent } = require("../../agents/aibitat/utils/summarize");

/**
 * Execute a web scraping flow step
 * @param {Object} config Flow step configuration
 * @param {Object} context Execution context with introspect function
 * @returns {Promise<string>} Scraped content
 */
async function executeWebScraping(config, context) {
  const { url, captureAs = "text" } = config;
  const { introspect, model, provider } = context;

  if (!url) {
    throw new Error("URL is required for web scraping");
  }

  // Remap the captureAs to the correct mode for the CollectorApi
  const captureMode = captureAs === "querySelector" ? "html" : captureAs;
  introspect(`Scraping the content of ${url} as ${captureAs}`);
  const { success, content } = await new CollectorApi()
    .getLinkContent(url, captureMode)
    .then((res) => {
      if (captureAs !== "querySelector") return res;
      return parseHTMLwithSelector(res.content, config.querySelector, context);
    });

  if (!success) {
    introspect(`Could not scrape ${url}. Cannot use this page's content.`);
    throw new Error("URL could not be scraped and no content was found.");
  }

  introspect(`Successfully scraped content from ${url}`);

  if (!content || content?.length === 0) {
    throw new Error("There was no content to be collected or read.");
  }

  const tokenCount = new TokenManager(model).countFromString(content);
  const contextLimit = Provider.contextLimit(provider, model);

  if (tokenCount < contextLimit) {
    return content;
  }

  introspect(
    `This page's content is way too long. I will summarize it right now.`
  );
  const summary = await summarizeContent({
    provider,
    model,
    content,
  });

  introspect(`Successfully summarized content`);

  return summary;
}

/**
 * Parse HTML with a CSS selector
 * @param {string} html - The HTML to parse
 * @param {string|null} selector - The CSS selector to use (as text string)
 * @param {{introspect: Function}} context - The context object
 * @returns {Object} The parsed content
 */
function parseHTMLwithSelector(html, selector = null, context) {
  if (!selector || selector.length === 0) {
    context.introspect("No selector provided. Returning the entire HTML.");
    return { success: true, content: html };
  }

  const Cheerio = require("cheerio");
  const $ = Cheerio.load(html);
  const selectedElements = $(selector);

  let content;
  if (selectedElements.length === 0) {
    return { success: false, content: null };
  } else if (selectedElements.length === 1) {
    content = selectedElements.html();
  } else {
    context.introspect(
      `Found ${selectedElements.length} elements matching selector: ${selector}`
    );
    content = selectedElements
      .map((_, element) => $(element).html())
      .get()
      .join("\n");
  }
  return { success: true, content };
}

module.exports = executeWebScraping;