Scrapegraph-ai/scrapegraphai/nodes/fetch_node.py
Harsh Abasaheb Chavan e81a4ed745 feat: Add configurable timeout to FetchNode
- Add timeout parameter to FetchNode (default: 30 seconds)
- Apply timeout to requests.get() calls to prevent indefinite hangs
- Implement timeout for PDF parsing using ThreadPoolExecutor
- Propagate timeout to ChromiumLoader via loader_kwargs
- Add comprehensive unit tests for timeout functionality
- Fully backward compatible (timeout can be disabled with None)

Fixes issue with requests.get() and PDF parsing blocking indefinitely
on slow/unresponsive servers or large documents.

Usage:
  node_config={'timeout': 30}  # Custom timeout
  node_config={'timeout': None}  # Disable timeout
  node_config={}  # Use default 30s timeout
2025-11-01 09:08:13 +00:00

393 lines
14 KiB
Python

"""
FetchNode Module
"""
import json
from typing import List, Optional
import concurrent.futures
import requests
from langchain_community.document_loaders import PyPDFLoader
from langchain_core.documents import Document
from langchain_openai import AzureChatOpenAI, ChatOpenAI
from ..docloaders import ChromiumLoader
from ..utils.cleanup_html import cleanup_html
from ..utils.convert_to_md import convert_to_md
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, node_config)
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.use_soup = (
False if node_config is None else node_config.get("use_soup", False)
)
self.loader_kwargs = (
{} if node_config is None else node_config.get("loader_kwargs", {})
)
self.llm_model = {} if node_config is None else node_config.get("llm_model", {})
self.force = False if node_config is None else node_config.get("force", False)
self.script_creator = (
False if node_config is None else node_config.get("script_creator", False)
)
self.openai_md_enabled = (
False
if node_config is None
else node_config.get("openai_md_enabled", False)
)
# Timeout in seconds for blocking operations (HTTP requests, PDF parsing, etc.).
# If set to None, no timeout will be applied.
self.timeout = None if node_config is None else node_config.get("timeout", 30)
self.cut = False if node_config is None else node_config.get("cut", True)
self.browser_base = (
None if node_config is None else node_config.get("browser_base", None)
)
self.scrape_do = (
None if node_config is None else node_config.get("scrape_do", None)
)
self.storage_state = (
None if node_config is None else node_config.get("storage_state", None)
)
def execute(self, state):
"""
Executes the node's logic to fetch HTML content from a specified URL and
update the state with this content.
"""
self.logger.info(f"--- Executing {self.node_name} Node ---")
input_keys = self.get_input_keys(state)
input_data = [state[key] for key in input_keys]
source = input_data[0]
input_type = input_keys[0]
handlers = {
"json_dir": self.handle_directory,
"xml_dir": self.handle_directory,
"csv_dir": self.handle_directory,
"pdf_dir": self.handle_directory,
"md_dir": self.handle_directory,
"pdf": self.handle_file,
"csv": self.handle_file,
"json": self.handle_file,
"xml": self.handle_file,
"md": self.handle_file,
}
if input_type in handlers:
return handlers[input_type](state, input_type, source)
elif input_type == "local_dir":
return self.handle_local_source(state, source)
elif input_type == "url":
return self.handle_web_source(state, source)
else:
raise ValueError(f"Invalid input type: {input_type}")
def handle_directory(self, state, input_type, source):
"""
Handles the directory by compressing the source document and updating the state.
Parameters:
state (dict): The current state of the graph.
input_type (str): The type of input being processed.
source (str): The source document to be compressed.
Returns:
dict: The updated state with the compressed document.
"""
compressed_document = [source]
state.update({self.output[0]: compressed_document})
return state
def handle_file(self, state, input_type, source):
"""
Loads the content of a file based on its input type.
Parameters:
state (dict): The current state of the graph.
input_type (str): The type of the input file (e.g., "pdf", "csv", "json", "xml", "md").
source (str): The path to the source file.
Returns:
dict: The updated state with the compressed document.
The function supports the following input types:
- "pdf": Uses PyPDFLoader to load the content of a PDF file.
- "csv": Reads the content of a CSV file using pandas and converts it to a string.
- "json": Loads the content of a JSON file.
- "xml": Reads the content of an XML file as a string.
- "md": Reads the content of a Markdown file as a string.
"""
compressed_document = self.load_file_content(source, input_type)
# return self.update_state(state, compressed_document)
state.update({self.output[0]: compressed_document})
return state
def load_file_content(self, source, input_type):
"""
Loads the content of a file based on its input type.
Parameters:
source (str): The path to the source file.
input_type (str): The type of the input file (e.g., "pdf", "csv", "json", "xml", "md").
Returns:
list: A list containing a Document object with the loaded content and metadata.
"""
if input_type == "pdf":
loader = PyPDFLoader(source)
# PyPDFLoader.load() can be blocking for large PDFs. Run it in a thread and
# enforce the configured timeout if provided.
if self.timeout is None:
return loader.load()
else:
with concurrent.futures.ThreadPoolExecutor(max_workers=1) as executor:
future = executor.submit(loader.load)
try:
return future.result(timeout=self.timeout)
except concurrent.futures.TimeoutError:
raise TimeoutError(
f"PDF parsing exceeded timeout of {self.timeout} seconds"
)
elif input_type == "csv":
try:
import pandas as pd
except ImportError:
raise ImportError(
"pandas is not installed. Please install it using `pip install pandas`."
)
return [
Document(
page_content=str(pd.read_csv(source)), metadata={"source": "csv"}
)
]
elif input_type == "json":
with open(source, encoding="utf-8") as f:
return [
Document(
page_content=str(json.load(f)), metadata={"source": "json"}
)
]
elif input_type == "xml" or input_type == "md":
with open(source, "r", encoding="utf-8") as f:
data = f.read()
return [Document(page_content=data, metadata={"source": input_type})]
def handle_local_source(self, state, source):
"""
Handles the local source by fetching HTML content, optionally converting it to Markdown,
and updating the state.
Parameters:
state (dict): The current state of the graph.
source (str): The HTML content from the local source.
Returns:
dict: The updated state with the processed content.
Raises:
ValueError: If the source is empty or contains only whitespace.
"""
self.logger.info(f"--- (Fetching HTML from: {source}) ---")
if not source.strip():
raise ValueError("No HTML body content found in the local source.")
parsed_content = source
if (
(
isinstance(self.llm_model, ChatOpenAI)
or isinstance(self.llm_model, AzureChatOpenAI)
)
and not self.script_creator
or self.force
and not self.script_creator
):
parsed_content = convert_to_md(source)
else:
parsed_content = source
compressed_document = [
Document(page_content=parsed_content, metadata={"source": "local_dir"})
]
# return self.update_state(state, compressed_document)
state.update({self.output[0]: compressed_document})
return state
def handle_web_source(self, state, source):
"""
Handles the web source by fetching HTML content from a URL,
optionally converting it to Markdown, and updating the state.
Parameters:
state (dict): The current state of the graph.
source (str): The URL of the web source to fetch HTML content from.
Returns:
dict: The updated state with the processed content.
Raises:
ValueError: If the fetched HTML content is empty or contains only whitespace.
"""
self.logger.info(f"--- (Fetching HTML from: {source}) ---")
if self.use_soup:
# Apply configured timeout to blocking HTTP requests. If timeout is None,
# don't pass the timeout argument (requests will block until completion).
if self.timeout is None:
response = requests.get(source)
else:
response = requests.get(source, timeout=self.timeout)
if response.status_code == 200:
if not response.text.strip():
raise ValueError("No HTML body content found in the response.")
if not self.cut:
parsed_content = cleanup_html(response, source)
if (
isinstance(self.llm_model, (ChatOpenAI, AzureChatOpenAI))
and not self.script_creator
or (self.force and not self.script_creator)
):
parsed_content = convert_to_md(source, parsed_content)
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:
loader_kwargs = self.node_config.get("loader_kwargs", {})
# If a global timeout is configured on the node and no loader-specific timeout
# was provided, propagate it to ChromiumLoader so it can apply the same limit.
if "timeout" not in loader_kwargs and self.timeout is not None:
loader_kwargs["timeout"] = self.timeout
if self.browser_base:
try:
from ..docloaders.browser_base import browser_base_fetch
except ImportError:
raise ImportError(
"""The browserbase module is not installed.
Please install it using `pip install browserbase`."""
)
data = browser_base_fetch(
self.browser_base.get("api_key"),
self.browser_base.get("project_id"),
[source],
)
document = [
Document(page_content=content, metadata={"source": source})
for content in data
]
elif self.scrape_do:
from ..docloaders.scrape_do import scrape_do_fetch
if (
(self.scrape_do.get("use_proxy") is None)
or self.scrape_do.get("geoCode") is None
or self.scrape_do.get("super_proxy") is None
):
data = scrape_do_fetch(self.scrape_do.get("api_key"), source)
else:
data = scrape_do_fetch(
self.scrape_do.get("api_key"),
source,
self.scrape_do.get("use_proxy"),
self.scrape_do.get("geoCode"),
self.scrape_do.get("super_proxy"),
)
document = [Document(page_content=data, metadata={"source": source})]
else:
loader = ChromiumLoader(
[source],
headless=self.headless,
storage_state=self.storage_state,
**loader_kwargs,
)
document = loader.load()
if not document or not document[0].page_content.strip():
raise ValueError(
"""No HTML body content found in
the document fetched by ChromiumLoader."""
)
parsed_content = document[0].page_content
if (
(
isinstance(self.llm_model, ChatOpenAI)
or isinstance(self.llm_model, AzureChatOpenAI)
)
and not self.script_creator
or self.force
and not self.script_creator
and not self.openai_md_enabled
):
parsed_content = convert_to_md(document[0].page_content, parsed_content)
compressed_document = [
Document(page_content=parsed_content, metadata={"source": "html file"})
]
state["doc"] = document
state.update(
{
self.output[0]: compressed_document,
}
)
return state