DOC switch from .extract to get/getall API in docs

Also, response.urljoin is added in a few places, for robustness.

docs/intro/tutorial.rst

@@ -254,7 +254,7 @@ data.
 
 To extract the text from the title above, you can do::
 
-    >>> response.css('title::text').extract()
+    >>> response.css('title::text').getall()
     ['Quotes to Scrape']
 
 There are two things to note here: one is that we've added ``::text`` to the
@@ -262,12 +262,12 @@ CSS query, to mean we want to select only the text elements directly inside
 ``<title>`` element.  If we don't specify ``::text``, we'd get the full title
 element, including its tags::
 
-    >>> response.css('title').extract()
+    >>> response.css('title').getall()
     ['<title>Quotes to Scrape</title>']
 
-The other thing is that the result of calling ``.extract()`` is a list, because
-we're dealing with an instance of :class:`~scrapy.selector.SelectorList`.  When
-you know you just want the first result, as in this case, you can do::
+The other thing is that the result of calling ``.getall()`` is a list: it is
+possible that a selector returns more than one result, so we extract them all.
+When you know you just want the first result, as in this case, you can do::
 
     >>> response.css('title::text').get()
     'Quotes to Scrape'
@@ -392,10 +392,10 @@ using the ``quote`` object we just created::
     >>> author
     'Albert Einstein'
 
-Given that the tags are a list of strings, we can use the ``.extract()`` method
+Given that the tags are a list of strings, we can use the ``.getall()`` method
 to get all of them::
 
-    >>> tags = quote.css("div.tags a.tag::text").extract()
+    >>> tags = quote.css("div.tags a.tag::text").getall()
     >>> tags
     ['change', 'deep-thoughts', 'thinking', 'world']
 
@@ -405,7 +405,7 @@ quotes elements and put them together into a Python dictionary::
     >>> for quote in response.css("div.quote"):
     ...     text = quote.css("span.text::text").get()
     ...     author = quote.css("small.author::text").get()
-    ...     tags = quote.css("div.tags a.tag::text").extract()
+    ...     tags = quote.css("div.tags a.tag::text").getall()
     ...     print(dict(text=text, author=author, tags=tags))
     {'tags': ['change', 'deep-thoughts', 'thinking', 'world'], 'author': 'Albert Einstein', 'text': '“The world as we have created it is a process of our thinking. It cannot be changed without changing our thinking.”'}
     {'tags': ['abilities', 'choices'], 'author': 'J.K. Rowling', 'text': '“It is our choices, Harry, that show what we truly are, far more than our abilities.”'}
@@ -438,7 +438,7 @@ in the callback, as you can see below::
                 yield {
                     'text': quote.css('span.text::text').get(),
                     'author': quote.css('small.author::text').get(),
-                    'tags': quote.css('div.tags a.tag::text').extract(),
+                    'tags': quote.css('div.tags a.tag::text').getall(),
                 }
 
 If you run this spider, it will output the extracted data with the log::
@@ -543,7 +543,7 @@ page, extracting data from it::
                 yield {
                     'text': quote.css('span.text::text').get(),
                     'author': quote.css('small.author::text').get(),
-                    'tags': quote.css('div.tags a.tag::text').extract(),
+                    'tags': quote.css('div.tags a.tag::text').getall(),
                 }
 
             next_page = response.css('li.next a::attr(href)').get()
@@ -594,7 +594,7 @@ As a shortcut for creating Request objects you can use
                 yield {
                     'text': quote.css('span.text::text').get(),
                     'author': quote.css('span small::text').get(),
-                    'tags': quote.css('div.tags a.tag::text').extract(),
+                    'tags': quote.css('div.tags a.tag::text').getall(),
                 }
 
             next_page = response.css('li.next a::attr(href)').get()

docs/topics/shell.rst

@@ -184,8 +184,8 @@ After that, we can start playing with the objects::
 
     >>> fetch("https://reddit.com")
 
-    >>> response.xpath('//title/text()').extract()
-    ['reddit: the front page of the internet']
+    >>> response.xpath('//title/text()').get()
+    'reddit: the front page of the internet'
 
     >>> request = request.replace(method="POST")
 

docs/topics/spiders.rst

@@ -229,11 +229,11 @@ Return multiple Requests and items from a single callback::
         ]
 
         def parse(self, response):
-            for h3 in response.xpath('//h3').extract():
+            for h3 in response.xpath('//h3').getall():
                 yield {"title": h3}
 
-            for url in response.xpath('//a/@href').extract():
-                yield scrapy.Request(url, callback=self.parse)
+            for href in response.xpath('//a/@href').getall():
+                yield scrapy.Request(response.urljoin(href), self.parse)
 
 Instead of :attr:`~.start_urls` you can use :meth:`~.start_requests` directly;
 to give data more structure you can use :ref:`topics-items`::
@@ -251,11 +251,11 @@ to give data more structure you can use :ref:`topics-items`::
             yield scrapy.Request('http://www.example.com/3.html', self.parse)
 
         def parse(self, response):
-            for h3 in response.xpath('//h3').extract():
+            for h3 in response.xpath('//h3').getall():
                 yield MyItem(title=h3)
 
-            for url in response.xpath('//a/@href').extract():
-                yield scrapy.Request(url, callback=self.parse)
+            for href in response.xpath('//a/@href').getall():
+                yield scrapy.Request(response.urljoin(href), self.parse)
 
 .. _spiderargs:
 
@@ -545,7 +545,7 @@ These spiders are pretty easy to use, let's have a look at one example::
         itertag = 'item'
 
         def parse_node(self, response, node):
-            self.logger.info('Hi, this is a <%s> node!: %s', self.itertag, ''.join(node.extract()))
+            self.logger.info('Hi, this is a <%s> node!: %s', self.itertag, ''.join(node.getall()))
 
             item = TestItem()
             item['id'] = node.xpath('@id').get()