How to access scrapy settings from item Pipeline

Question

How do I access the scrapy settings in settings.py from the item pipeline. The documentation mentions it can be accessed through the crawler in extensions, but I don't see how to access the crawler in the pipelines.

Answer 1

UPDATE (2020-10-28)
Please note that this answer is now ~ 7years old, so it's validity can no longer be ensured.

The way to access your Scrapy settings (as defined in settings.py) from within your_spider.py is simple. All other answers are way too complicated. The reason for this is the very poor maintenance of the Scrapy documentation, combined with many recent updates & changes. Neither in the "Settings" documentation "How to access settings", nor in the "Settings API" have they bothered giving any workable example. Here's an example, how to get your current USER_AGENT string.

Just add the following lines to your_spider.py:

# To get your settings from (settings.py):
from scrapy.utils.project import get_project_settings
...
class YourSpider(BaseSpider):
    ...
    def parse(self, response):
        ...
        settings = get_project_settings()
        print "Your USER_AGENT is:\n%s" % (settings.get('USER_AGENT'))
        ...

As you can see, there's no need to use @classmethod or re-define the from_crawler() or __init__() functions. Hope this helps.

PS. I'm still not sure why using from scrapy.settings import Settings doesn't work the same way, since it would be the more obvious choice of import?