"""" FetchNode Module """ import json from typing import List, Optional import pandas as pd import requests from langchain_community.document_loaders import PyPDFLoader from langchain_core.documents import Document from ..docloaders import ChromiumLoader from ..utils.cleanup_html import cleanup_html from ..utils.logging import get_logger from .base_node import BaseNode class FetchNode(BaseNode): """ A node responsible for fetching the HTML content of a specified URL and updating the graph's state with this content. It uses ChromiumLoader to fetch the content from a web page asynchronously (with proxy protection). This node acts as a starting point in many scraping workflows, preparing the state with the necessary HTML content for further processing by subsequent nodes in the graph. Attributes: headless (bool): A flag indicating whether the browser should run in headless mode. verbose (bool): A flag indicating whether to print verbose output during execution. Args: input (str): Boolean expression defining the input keys needed from the state. output (List[str]): List of output keys to be updated in the state. node_config (Optional[dict]): Additional configuration for the node. node_name (str): The unique identifier name for the node, defaulting to "Fetch". """ def __init__( self, input: str, output: List[str], node_config: Optional[dict] = None, node_name: str = "Fetch", ): super().__init__(node_name, "node", input, output, 1) self.headless = ( True if node_config is None else node_config.get("headless", True) ) self.verbose = ( False if node_config is None else node_config.get("verbose", False) ) self.useSoup = ( False if node_config is None else node_config.get("useSoup", False) ) self.loader_kwargs = ( {} if node_config is None else node_config.get("loader_kwargs", {}) ) def execute(self, state): """ Executes the node's logic to fetch HTML content from a specified URL and update the state with this content. Args: state (dict): The current state of the graph. The input keys will be used to fetch the correct data types from the state. Returns: dict: The updated state with a new output key containing the fetched HTML content. Raises: KeyError: If the input key is not found in the state, indicating that the necessary information to perform the operation is missing. """ self.logger.info(f"--- Executing {self.node_name} Node ---") # Interpret input keys based on the provided input expression input_keys = self.get_input_keys(state) # Fetching data from the state based on the input keys input_data = [state[key] for key in input_keys] source = input_data[0] if ( input_keys[0] == "json_dir" or input_keys[0] == "xml_dir" or input_keys[0] == "csv_dir" or input_keys[0] == "pdf_dir" ): compressed_document = [ source ] state.update({self.output[0]: compressed_document}) return state # handling for pdf elif input_keys[0] == "pdf": loader = PyPDFLoader(source) compressed_document = loader.load() state.update({self.output[0]: compressed_document}) return state elif input_keys[0] == "csv": compressed_document = [ Document( page_content=str(pd.read_csv(source)), metadata={"source": "csv"} ) ] state.update({self.output[0]: compressed_document}) return state elif input_keys[0] == "json": f = open(source) compressed_document = [ Document(page_content=str(json.load(f)), metadata={"source": "json"}) ] state.update({self.output[0]: compressed_document}) return state elif input_keys[0] == "xml": with open(source, "r", encoding="utf-8") as f: data = f.read() compressed_document = [ Document(page_content=data, metadata={"source": "xml"}) ] state.update({self.output[0]: compressed_document}) return state elif self.input == "pdf_dir": pass elif not source.startswith("http"): title, minimized_body, link_urls, image_urls = cleanup_html(source, source) parsed_content = f"Title: {title}, Body: {minimized_body}, Links: {link_urls}, Images: {image_urls}" compressed_document = [ Document(page_content=parsed_content, metadata={"source": "local_dir"}) ] elif self.useSoup: response = requests.get(source) if response.status_code == 200: title, minimized_body, link_urls, image_urls = cleanup_html( response.text, source ) parsed_content = f"Title: {title}, Body: {minimized_body}, Links: {link_urls}, Images: {image_urls}" compressed_document = [Document(page_content=parsed_content)] else: self.logger.warning( f"Failed to retrieve contents from the webpage at url: {source}" ) else: loader_kwargs = {} if self.node_config is not None: loader_kwargs = self.node_config.get("loader_kwargs", {}) loader = ChromiumLoader([source], headless=self.headless, **loader_kwargs) document = loader.load() title, minimized_body, link_urls, image_urls = cleanup_html( str(document[0].page_content), source ) parsed_content = f"Title: {title}, Body: {minimized_body}, Links: {link_urls}, Images: {image_urls}" compressed_document = [ Document(page_content=parsed_content, metadata={"source": source}) ] state.update( { self.output[0]: compressed_document, self.output[1]: link_urls, self.output[2]: image_urls, } ) return state