diff --git a/docs/topics/_images/scrapy_architecture_02.png b/docs/topics/_images/scrapy_architecture_02.png index 80be02078..5fe393f22 100644 Binary files a/docs/topics/_images/scrapy_architecture_02.png and b/docs/topics/_images/scrapy_architecture_02.png differ diff --git a/docs/topics/architecture.rst b/docs/topics/architecture.rst index 39e54ee99..84c053660 100644 --- a/docs/topics/architecture.rst +++ b/docs/topics/architecture.rst @@ -29,20 +29,20 @@ Data flow The data flow in Scrapy is controlled by the execution engine, and goes like this: -1. The :ref:`Engine ` gets the first URLs to crawl from the +1. The :ref:`Engine ` gets the first Requests to crawl from the :ref:`Spider `. -2. The :ref:`Engine ` schedules the URLs in the - :ref:`Scheduler ` as Requests and asks for the - next URLs to crawl. +2. The :ref:`Engine ` schedules the Requests in the + :ref:`Scheduler ` and asks for the + next Requests to crawl. -3. The :ref:`Scheduler ` returns the next URLs to crawl +3. The :ref:`Scheduler ` returns the next Requests to the :ref:`Engine `. -4. The :ref:`Engine ` sends the URLs to the +4. The :ref:`Engine ` sends the Requests to the :ref:`Downloader `, passing through the :ref:`Downloader Middleware ` - (request direction). + (requests direction). 5. Once the page finishes downloading the :ref:`Downloader ` generates a Response (with @@ -62,10 +62,11 @@ this: :ref:`Spider Middleware ` (output direction). 8. The :ref:`Engine ` sends processed items to - :ref:`Item Pipelines ` and processed Requests to - the :ref:`Scheduler `. + :ref:`Item Pipelines `, then sends processed Requests to + the :ref:`Scheduler ` and asks for the next + Requests to crawl. -9. The process repeats (from step 1) until there are no more requests from the +9. The process repeats (from step 2) until there are no more requests from the :ref:`Scheduler `. Components @@ -102,7 +103,7 @@ Spiders ------- Spiders are custom classes written by Scrapy users to parse responses and -extract items (aka scraped items) from them or additional URLs (requests) to +extract items (aka scraped items) from them or additional requests to follow. For more information see :ref:`topics-spiders`. .. _component-pipelines: