getting_started.rst

Getting started

Table of Contents

• Minimal implementation
• Running the crawler
  • In the foreground
  • In the background

Minimal implementation

# example.py

from nyawc.Options import Options
from nyawc.Crawler import Crawler
from nyawc.CrawlerActions import CrawlerActions
from nyawc.http.Request import Request

def cb_crawler_before_start():
    print("Crawler started.")

def cb_crawler_after_finish(queue):
    print("Crawler finished.")
    print("Found " + str(queue.count_finished) + " requests.")

def cb_request_before_start(queue, queue_item):
    print("Starting: {}".format(queue_item.request.url))
    return CrawlerActions.DO_CONTINUE_CRAWLING

def cb_request_after_finish(queue, queue_item, new_queue_items):
    print("Finished: {}".format(queue_item.request.url))
    return CrawlerActions.DO_CONTINUE_CRAWLING

options = Options()

options.callbacks.crawler_before_start = cb_crawler_before_start # Called before the crawler starts crawling. Default is a null route.
options.callbacks.crawler_after_finish = cb_crawler_after_finish # Called after the crawler finished crawling. Default is a null route.
options.callbacks.request_before_start = cb_request_before_start # Called before the crawler starts a new request. Default is a null route.
options.callbacks.request_after_finish = cb_request_after_finish # Called after the crawler finishes a request. Default is a null route.

crawler = Crawler(options)
crawler.start_with(Request("https://finnwea.com/"))

Running the crawler

In the foreground

$ python example.py

In the background

$ python -u example.py > output.log