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PyCharm IDE breakpoints don't work in subprocess call

I have a Flask project running with a subprocess call to a Scrapy spider:
class Utilities(object):
#staticmethod
def scrape(inputs):
job_id = str(uuid.uuid4())
project_folder = os.path.abspath(os.path.dirname(__file__))
subprocess.call(['scrapy', 'crawl', "ExampleCrawler", "-a", "inputs=" + str(inputs), "-s", "JOB_ID=" + job_id],
cwd="%s/scraper" % project_folder)
return job_id
Even though I have 'Attach to subprocess automatically while debugging' enabled in the projects' Python debugger, the breakpoints inside the spider won't work. The first breakpoint which works again would be one on return job_id.
Here is a part of the code from the spider where I expect the breakpoints to work:
from scrapy.http import FormRequest
from scrapy.spiders import Spider
from scrapy.loader import ItemLoader
from Handelsregister_Scraper.scraper.items import Product
import re
class ExampleCrawler(Spider):
name = "ExampleCrawler"
def __init__(self, inputs='', *args, **kwargs):
super(ExampleCrawler, self).__init__(*args, **kwargs)
self.start_urls = ['https://www.example-link.com']
self.inputs = inputs
def parse(self, response):
yield FormRequest(self.start_urls[0], callback=self.parse_list_elements, formdata=self.inputs)
I can't find any solution to this other than enabling said option which i did.
Any suggestions how to get breakpoints inside the spider work?

debugger doesn't work because is not a subprocess, but an external call. see this answer for possible workarounds.

Try configuring this python running configuration in "Edit Configurations". After that, run in debug mode.

How to specify log file name with spider's name in scrapy?

I'm using scrapy,in my scrapy project,I created several spider classes,as the official document said,I used this way to specify log file name:
def logging_to_file(file_name):
"""
#rtype: logging
#type file_name:str
#param file_name:
#return:
"""
import logging
from scrapy.utils.log import configure_logging
configure_logging(install_root_handler=False)
logging.basicConfig(
filename=filename+'.txt',
filemode='a',
format='%(levelname)s: %(message)s',
level=logging.DEBUG,
)
Class Spider_One(scrapy.Spider):
name='xxx1'
logging_to_file(name)
......
Class Spider_Two(scrapy.Spider):
name='xxx2'
logging_to_file(name)
......
Now,if I start Spider_One,everything is correct!But,if I start Spider Two,the log file of Spider Two will also be named with the name of Spider One!
I have searched many answers from google and stackoverflow,but unfortunately,none worked!
I am using python 2.7 & scrapy 1.1!
Hope anyone can help me!

It's because you initiate logging_to_file every time when you load up your package. You are using a class variable here where you should use instance variable.
When python loads in your package or module ir loads every class and so on.
class MyClass:
# everything you do here is loaded everytime when package is loaded
name = 'something'
def __init__(self):
# everything you do here is loaded ONLY when the object is created
# using this class
To resolve your issue just move logging_to_file function call to your spiders __init__() method.
class MyClass(Spider):
name = 'xx1'
def __init__(self):
super(MyClass, self).__init__()
logging_to_file(self.name)

One option is to define the LOG_FILE setting in Spider.custom_settings:
from scrapy import Spider
class MySpider(Spider):
name = "myspider"
start_urls = ["https://toscrape.com"]
custom_settings = {
"LOG_FILE": f"{name}.log",
}
def parse(self, response):
pass
However, because logging starts before the spider custom settings are read, the first few lines of the log will still go into the standard error output.

Scrapy: Pass arguments to spider that is defined in /spiders directory

I'm writing a script that uses CrawlerProcess to run a spider of class MySpider defined in mybot/spiders/myspider.py.
Here's the relevant part of my code:
# in main.py
from scrapy.crawler import CrawlerProcess
from scrapy import signals
from scrapy.utils.project import get_project_settings
from scrapy.xlib.pydispatch import dispatcher
items = []
settings = get_project_settings()
process = CrawlerProcess(settings)
process.crawl("joe", domain='dictionary.com')
def add_item(item):
items.append(item)
dispatcher.connect(add_item, signals.item_passed) # adds result from spider to items
process.start()
.
#in /spiders/myspider.py
from scrapy.spiders import Spider
from mybot.items import MyItem
name = "joe"
allowed_domains = ["dictionary.com"]
start_urls = ["http://dictionary.reference.com/"]
for sel in response.xpath('//tr[#class="alt"]'):
new_item = MyItem()
new_item['name'] = sel.xpath('td/a/text()')[0].extract()
yield(new_item)
Now, I want to change the program so that I can pass some other start_url to the spider from main.py. It looks like I can pass the allowed_domains argument to the spider via
process.crawl("joe", domain='dictionary.com')
but I don't know how to generalize that.
I think I have to redefine the MySpider's constructor to accept an optional argument, but it doesn't look like the spider is created in main.py
(and in fact, the command new_spider = MySpider() returns the error global name 'MySpider' is not defined.
So my question is twofold:
How do I change the spider's constructor?
How do I pass the start_urls to the spider from main.py?
Or is there perhaps a different solution altogether?

Scrapy spider not following links when using Celery

I'm a writing a crawler in Python that crawls all pages in a given domain, as part of a domain-specific search engine . I'am using Django, Scrapy, and Celery for achieving this. The scenario is as follows:
I receive a domain name from the user and call the crawl task inside the view, passing the domain as an argument:
crawl.delay(domain)
The task itself just calls a function that starts the crawling process:
from .crawler.crawl import run_spider
from celery import shared_task
#shared_task
def crawl(domain):
return run_spider(domain)
run_spider starts the crawling process, as in this SO answer, replacing MySpider with WebSpider.
WebSpider inherits from CrawlSpider and I'm using it now just to test functionality. The only rule defined takes an SgmlLinkExtractor instance and a callback function parse_page which simply extracts the response url and the page title, populates a new DjangoItem (HTMLPageItem) with them and saves it into the database (not so efficient, I know).
from urlparse import urlparse
from scrapy.contrib.linkextractors.sgml import SgmlLinkExtractor
from ..items import HTMLPageItem
from scrapy.selector import Selector
from scrapy.contrib.spiders import Rule, CrawlSpider
class WebSpider(CrawlSpider):
name = "web"
def __init__(self, **kw):
super(WebSpider, self).__init__(**kw)
url = kw.get('domain') or kw.get('url')
if not (url.startswith('http://') or url.startswith('https://')):
url = "http://%s/" % url
self.url = url
self.allowed_domains = [urlparse(url).hostname.lstrip('www.')]
self.start_urls = [url]
self.rules = [
Rule(SgmlLinkExtractor(
allow_domains=self.allowed_domains,
unique=True), callback='parse_page', follow=True)
]
def parse_start_url(self, response):
return self.parse_page(response)
def parse_page(self, response):
sel = Selector(response)
item = HTMLPageItem()
item['url'] = response.request.url
item['title'] = sel.xpath('//title/text()').extract()[0]
item.save()
return item
The problem is the crawler only crawls the start_urls and does not follow links (or call the callback function) when following this scenario and using Celery. However calling run_spider through python manage.py shell works just fine!
Another problem is that Item Pipelines and logging are not working with Celery. This is making debugging much harder. I think these problems might be related.

So after inspecting Scrapy's code and enabling Celery logging, by inserting these two lines in web_spider.py:
from celery.utils.log import get_task_logger
logger = get_task_logger(__name__)
I was able to locate the problem:
In the initialization function of WebSpider:
super(WebSpider, self).__init__(**kw)
The __init__ function of the parent CrawlSpider calls the _compile_rules function which in short copies the rules from self.rules to self._rules while making some changes. self._rules is what the spider uses when it checks for rules . Calling the initialization function of CrawlSpider before defining the rules led to an empty self._rules, hence no links were followed.
Moving the super(WebSpider, self).__init__(**kw) line to the last line of WebSpider's __init__ fixed the problem.
Update: There is a little mistake in code from the previously mentioned SO answer. It causes the reactor to hang after second call. The fix is simple, in WebCrawlerScript's __init__ method, simply move this line:
self.crawler.signals.connect(reactor.stop, signal=signals.spider_closed)
out of the if statement, as suggested in the comments there.
Update 2: I finally got pipelines to work! It was not a Celery problem. I realized that the settings module wasn't being read. It was simply an import problem. To fix it:
Set the environment variable SCRAPY_SETTINGS_MODULE in your django project's settings module myproject/settings.py:
import os
os.environ['SCRAPY_SETTINGS_MODULE'] = 'myapp.crawler.crawler.settings'
In your Scrapy settings module crawler/settings.py, add your Scrapy project path to sys.path so that relative imports in the settings file would work:
import sys
sys.path.append('/absolute/path/to/scrapy/project')
Change the paths to suit your case.

scrapy log issue

i have multiple spiders in one project , problem is right now i am defining LOG_FILE in SETTINGS like
LOG_FILE = "scrapy_%s.log" % datetime.now()
what i want is scrapy_SPIDERNAME_DATETIME
but i am unable to provide spidername in log_file name ..
i found
scrapy.log.start(logfile=None, loglevel=None, logstdout=None)
and called it in each spider init method but its not working ..
any help would be appreciated

The spider's __init__() is not early enough to call log.start() by itself since the log observer is already started at this point; therefore, you need to reinitialize the logging state to trick Scrapy into (re)starting it.
In your spider class file:
from datetime import datetime
from scrapy import log
from scrapy.spider import BaseSpider
class ExampleSpider(BaseSpider):
name = "example"
allowed_domains = ["example.com"]
start_urls = ["http://www.example.com/"]
def __init__(self, name=None, **kwargs):
LOG_FILE = "scrapy_%s_%s.log" % (self.name, datetime.now())
# remove the current log
# log.log.removeObserver(log.log.theLogPublisher.observers[0])
# re-create the default Twisted observer which Scrapy checks
log.log.defaultObserver = log.log.DefaultObserver()
# start the default observer so it can be stopped
log.log.defaultObserver.start()
# trick Scrapy into thinking logging has not started
log.started = False
# start the new log file observer
log.start(LOG_FILE)
# continue with the normal spider init
super(ExampleSpider, self).__init__(name, **kwargs)
def parse(self, response):
...
And the output file might look like:
scrapy_example_2012-08-25 12:34:48.823896.log

There should be a BOT_NAME in your settings.py. This is the project/spider name. So in your case, this would be
LOG_FILE = "scrapy_%s_%s.log" % (BOT_NAME, datetime.now())
This is pretty much the same that Scrapy does internally
But why not use log.msg. The docs clearly state that this is for spider specific stuff. It might be easier to use this and just extract/grep/... the different spider log messages from a big log file.
A more compicated approach would be to get the location of the spider SPIDER_MODULES list and load all spiders inside these package.

You can use Scrapy's Storage URI parameters in your settings.py file for FEED URI.
%(name)s
%(time)s
For example: /tmp/crawled/%(name)s/%(time)s.log