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https://github.com/rmax/scrapy-inline-requests

A decorator to write coroutine-like spider callbacks.
https://github.com/rmax/scrapy-inline-requests

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A decorator to write coroutine-like spider callbacks.

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======================
Scrapy Inline Requests
======================

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A decorator for writing coroutine-like spider callbacks.

* Free software: MIT license
* Documentation: https://scrapy-inline-requests.readthedocs.org.
* Python versions: 2.7, 3.4+

Quickstart
----------

The spider below shows a simple use case of scraping a page and following a few links:

.. code:: python

from inline_requests import inline_requests
from scrapy import Spider, Request

class MySpider(Spider):
name = 'myspider'
start_urls = ['http://httpbin.org/html']

@inline_requests
def parse(self, response):
urls = [response.url]
for i in range(10):
next_url = response.urljoin('?page=%d' % i)
try:
next_resp = yield Request(next_url)
urls.append(next_resp.url)
except Exception:
self.logger.info("Failed request %s", i, exc_info=True)

yield {'urls': urls}

See the ``examples/`` directory for a more complex spider.

.. warning::

The generator resumes its execution when a request's response is processed,
this means the generator won't be resume after yielding an item or a request
with it's own callback.

Known Issues
------------

* Middlewares can drop or ignore non-200 status responses causing the callback
to not continue its execution. This can be overcome by using the flag
``handle_httpstatus_all``. See the `httperror middleware`_ documentation.
* High concurrency and large responses can cause higher memory usage.
* This decorator assumes your method have the following signature
``(self, response)``.
* Wrapped requests may not be able to be serialized by persistent backends.
* Unless you know what you are doing, the decorated method must be a spider
method and return a **generator** instance.

.. _`httperror middleware`: http://doc.scrapy.org/en/latest/topics/spider-middleware.html#scrapy.spidermiddlewares.httperror.HttpErrorMiddleware