Files
crawl4ai/crawl4ai/web_crawler.back.py

357 lines
13 KiB
Python

import os, time
os.environ["TOKENIZERS_PARALLELISM"] = "false"
from pathlib import Path
from .models import UrlModel, CrawlResult
from .database import init_db, get_cached_url, cache_url, DB_PATH, flush_db
from .utils import *
from .chunking_strategy import *
from .extraction_strategy import *
from .crawler_strategy import *
from typing import List
from concurrent.futures import ThreadPoolExecutor
from .config import *
class WebCrawler:
def __init__(
self,
# db_path: str = None,
crawler_strategy: CrawlerStrategy = None,
always_by_pass_cache: bool = False,
verbose: bool = False,
):
# self.db_path = db_path
self.crawler_strategy = crawler_strategy or LocalSeleniumCrawlerStrategy(verbose=verbose)
self.always_by_pass_cache = always_by_pass_cache
# Create the .crawl4ai folder in the user's home directory if it doesn't exist
self.crawl4ai_folder = os.path.join(Path.home(), ".crawl4ai")
os.makedirs(self.crawl4ai_folder, exist_ok=True)
os.makedirs(f"{self.crawl4ai_folder}/cache", exist_ok=True)
# If db_path is not provided, use the default path
# if not db_path:
# self.db_path = f"{self.crawl4ai_folder}/crawl4ai.db"
# flush_db()
init_db()
self.ready = False
def warmup(self):
print("[LOG] 🌤️ Warming up the WebCrawler")
result = self.run(
url='https://crawl4ai.uccode.io/',
word_count_threshold=5,
extraction_strategy= NoExtractionStrategy(),
bypass_cache=False,
verbose = False
)
self.ready = True
print("[LOG] 🌞 WebCrawler is ready to crawl")
def fetch_page(
self,
url_model: UrlModel,
provider: str = DEFAULT_PROVIDER,
api_token: str = None,
extract_blocks_flag: bool = True,
word_count_threshold=MIN_WORD_THRESHOLD,
css_selector: str = None,
screenshot: bool = False,
use_cached_html: bool = False,
extraction_strategy: ExtractionStrategy = None,
chunking_strategy: ChunkingStrategy = RegexChunking(),
**kwargs,
) -> CrawlResult:
return self.run(
url_model.url,
word_count_threshold,
extraction_strategy or NoExtractionStrategy(),
chunking_strategy,
bypass_cache=url_model.forced,
css_selector=css_selector,
screenshot=screenshot,
**kwargs,
)
pass
def run_old(
self,
url: str,
word_count_threshold=MIN_WORD_THRESHOLD,
extraction_strategy: ExtractionStrategy = None,
chunking_strategy: ChunkingStrategy = RegexChunking(),
bypass_cache: bool = False,
css_selector: str = None,
screenshot: bool = False,
user_agent: str = None,
verbose=True,
**kwargs,
) -> CrawlResult:
if user_agent:
self.crawler_strategy.update_user_agent(user_agent)
extraction_strategy = extraction_strategy or NoExtractionStrategy()
extraction_strategy.verbose = verbose
# Check if extraction strategy is an instance of ExtractionStrategy if not raise an error
if not isinstance(extraction_strategy, ExtractionStrategy):
raise ValueError("Unsupported extraction strategy")
if not isinstance(chunking_strategy, ChunkingStrategy):
raise ValueError("Unsupported chunking strategy")
# make sure word_count_threshold is not lesser than MIN_WORD_THRESHOLD
if word_count_threshold < MIN_WORD_THRESHOLD:
word_count_threshold = MIN_WORD_THRESHOLD
# Check cache first
if not bypass_cache and not self.always_by_pass_cache:
cached = get_cached_url(url)
if cached:
return CrawlResult(
**{
"url": cached[0],
"html": cached[1],
"cleaned_html": cached[2],
"markdown": cached[3],
"extracted_content": cached[4],
"success": cached[5],
"media": json.loads(cached[6] or "{}"),
"links": json.loads(cached[7] or "{}"),
"metadata": json.loads(cached[8] or "{}"), # "metadata": "{}
"screenshot": cached[9],
"error_message": "",
}
)
# Initialize WebDriver for crawling
t = time.time()
if kwargs.get("js", None):
self.crawler_strategy.js_code = kwargs.get("js")
html = self.crawler_strategy.crawl(url)
base64_image = None
if screenshot:
base64_image = self.crawler_strategy.take_screenshot()
success = True
error_message = ""
# Extract content from HTML
try:
result = get_content_of_website(url, html, word_count_threshold, css_selector=css_selector)
metadata = extract_metadata(html)
if result is None:
raise ValueError(f"Failed to extract content from the website: {url}")
except InvalidCSSSelectorError as e:
raise ValueError(str(e))
cleaned_html = result.get("cleaned_html", "")
markdown = result.get("markdown", "")
media = result.get("media", [])
links = result.get("links", [])
# Print a profession LOG style message, show time taken and say crawling is done
if verbose:
print(
f"[LOG] 🚀 Crawling done for {url}, success: {success}, time taken: {time.time() - t} seconds"
)
extracted_content = []
if verbose:
print(f"[LOG] 🔥 Extracting semantic blocks for {url}, Strategy: {extraction_strategy.name}")
t = time.time()
# Split markdown into sections
sections = chunking_strategy.chunk(markdown)
# sections = merge_chunks_based_on_token_threshold(sections, CHUNK_TOKEN_THRESHOLD)
extracted_content = extraction_strategy.run(
url, sections,
)
extracted_content = json.dumps(extracted_content)
if verbose:
print(
f"[LOG] 🚀 Extraction done for {url}, time taken: {time.time() - t} seconds."
)
# Cache the result
cleaned_html = beautify_html(cleaned_html)
cache_url(
url,
html,
cleaned_html,
markdown,
extracted_content,
success,
json.dumps(media),
json.dumps(links),
json.dumps(metadata),
screenshot=base64_image,
)
return CrawlResult(
url=url,
html=html,
cleaned_html=cleaned_html,
markdown=markdown,
media=media,
links=links,
metadata=metadata,
screenshot=base64_image,
extracted_content=extracted_content,
success=success,
error_message=error_message,
)
def fetch_pages(
self,
url_models: List[UrlModel],
provider: str = DEFAULT_PROVIDER,
api_token: str = None,
extract_blocks_flag: bool = True,
word_count_threshold=MIN_WORD_THRESHOLD,
use_cached_html: bool = False,
css_selector: str = None,
screenshot: bool = False,
extraction_strategy: ExtractionStrategy = None,
chunking_strategy: ChunkingStrategy = RegexChunking(),
**kwargs,
) -> List[CrawlResult]:
extraction_strategy = extraction_strategy or NoExtractionStrategy()
def fetch_page_wrapper(url_model, *args, **kwargs):
return self.fetch_page(url_model, *args, **kwargs)
with ThreadPoolExecutor() as executor:
results = list(
executor.map(
fetch_page_wrapper,
url_models,
[provider] * len(url_models),
[api_token] * len(url_models),
[extract_blocks_flag] * len(url_models),
[word_count_threshold] * len(url_models),
[css_selector] * len(url_models),
[screenshot] * len(url_models),
[use_cached_html] * len(url_models),
[extraction_strategy] * len(url_models),
[chunking_strategy] * len(url_models),
*[kwargs] * len(url_models),
)
)
return results
def run(
self,
url: str,
word_count_threshold=MIN_WORD_THRESHOLD,
extraction_strategy: ExtractionStrategy = None,
chunking_strategy: ChunkingStrategy = RegexChunking(),
bypass_cache: bool = False,
css_selector: str = None,
screenshot: bool = False,
user_agent: str = None,
verbose=True,
**kwargs,
) -> CrawlResult:
extraction_strategy = extraction_strategy or NoExtractionStrategy()
extraction_strategy.verbose = verbose
if not isinstance(extraction_strategy, ExtractionStrategy):
raise ValueError("Unsupported extraction strategy")
if not isinstance(chunking_strategy, ChunkingStrategy):
raise ValueError("Unsupported chunking strategy")
if word_count_threshold < MIN_WORD_THRESHOLD:
word_count_threshold = MIN_WORD_THRESHOLD
# Check cache first
cached = None
extracted_content = None
if not bypass_cache and not self.always_by_pass_cache:
cached = get_cached_url(url)
if cached:
html = cached[1]
extracted_content = cached[2]
if screenshot:
screenshot = cached[9]
else:
if user_agent:
self.crawler_strategy.update_user_agent(user_agent)
html = self.crawler_strategy.crawl(url)
if screenshot:
screenshot = self.crawler_strategy.take_screenshot()
return self.process_html(url, html, extracted_content, word_count_threshold, extraction_strategy, chunking_strategy, css_selector, screenshot, verbose, bool(cached), **kwargs)
def process_html(
self,
url: str,
html: str,
extracted_content: str,
word_count_threshold: int,
extraction_strategy: ExtractionStrategy,
chunking_strategy: ChunkingStrategy,
css_selector: str,
screenshot: bool,
verbose: bool,
is_cached: bool,
**kwargs,
) -> CrawlResult:
t = time.time()
# Extract content from HTML
try:
result = get_content_of_website(url, html, word_count_threshold, css_selector=css_selector)
metadata = extract_metadata(html)
if result is None:
raise ValueError(f"Failed to extract content from the website: {url}")
except InvalidCSSSelectorError as e:
raise ValueError(str(e))
cleaned_html = result.get("cleaned_html", "")
markdown = result.get("markdown", "")
media = result.get("media", [])
links = result.get("links", [])
if verbose:
print(f"[LOG] 🚀 Crawling done for {url}, success: True, time taken: {time.time() - t} seconds")
if extracted_content is None:
if verbose:
print(f"[LOG] 🔥 Extracting semantic blocks for {url}, Strategy: {extraction_strategy.name}")
sections = chunking_strategy.chunk(markdown)
extracted_content = extraction_strategy.run(url, sections)
extracted_content = json.dumps(extracted_content)
if verbose:
print(f"[LOG] 🚀 Extraction done for {url}, time taken: {time.time() - t} seconds.")
screenshot = None if not screenshot else screenshot
if not is_cached:
cache_url(
url,
html,
cleaned_html,
markdown,
extracted_content,
True,
json.dumps(media),
json.dumps(links),
json.dumps(metadata),
screenshot=screenshot,
)
return CrawlResult(
url=url,
html=html,
cleaned_html=cleaned_html,
markdown=markdown,
media=media,
links=links,
metadata=metadata,
screenshot=screenshot,
extracted_content=extracted_content,
success=True,
error_message="",
)