mirrors/cpython
1
0
Fork 0
mirror of https://github.com/python/cpython.git synced 2025-11-03 03:22:27 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 8

Issue #12955: Change the urlopen() examples to use context managers where appropriate.

Browse source 
Patch by Martin Panter.
This commit is contained in:
Berker Peksag 2015-04-12 13:52:49 +03:00
parent 8ad751e024
commit 9575e1891f
5 changed files with 38 additions and 28 deletions
Download patch file Download diff file Expand all files Collapse all files

3
Doc/faq/library.rst
View file

@ -687,7 +687,8 @@ Yes. Here's a simple example that uses urllib.request::
### connect and send the server a path ### connect and send the server a path
req = urllib.request.urlopen('http://www.some-server.out-there' req = urllib.request.urlopen('http://www.some-server.out-there'
'/cgi-bin/some-cgi-script', data=qs) '/cgi-bin/some-cgi-script', data=qs)
msg, hdrs = req.read(), req.info() with req:
msg, hdrs = req.read(), req.info()
Note that in general for percent-encoded POST operations, query strings must be Note that in general for percent-encoded POST operations, query strings must be
quoted using :func:`urllib.parse.urlencode`. For example, to send quoted using :func:`urllib.parse.urlencode`. For example, to send

16
Doc/howto/urllib2.rst
View file

@ -53,8 +53,8 @@ Fetching URLs
The simplest way to use urllib.request is as follows:: The simplest way to use urllib.request is as follows::
import urllib.request import urllib.request
response = urllib.request.urlopen('http://python.org/') with urllib.request.urlopen('http://python.org/') as response:
html = response.read() html = response.read()
If you wish to retrieve a resource via URL and store it in a temporary location, If you wish to retrieve a resource via URL and store it in a temporary location,
you can do so via the :func:`~urllib.request.urlretrieve` function:: you can do so via the :func:`~urllib.request.urlretrieve` function::
@ -79,8 +79,8 @@ response::
import urllib.request import urllib.request
req = urllib.request.Request('http://www.voidspace.org.uk') req = urllib.request.Request('http://www.voidspace.org.uk')
response = urllib.request.urlopen(req) with urllib.request.urlopen(req) as response:
the_page = response.read() the_page = response.read()
Note that urllib.request makes use of the same Request interface to handle all URL Note that urllib.request makes use of the same Request interface to handle all URL
schemes. For example, you can make an FTP request like so:: schemes. For example, you can make an FTP request like so::
@ -117,8 +117,8 @@ library. ::
data = urllib.parse.urlencode(values) data = urllib.parse.urlencode(values)
data = data.encode('utf-8') # data should be bytes data = data.encode('utf-8') # data should be bytes
req = urllib.request.Request(url, data) req = urllib.request.Request(url, data)
response = urllib.request.urlopen(req) with urllib.request.urlopen(req) as response:
the_page = response.read() the_page = response.read()
Note that other encodings are sometimes required (e.g. for file upload from HTML Note that other encodings are sometimes required (e.g. for file upload from HTML
forms - see `HTML Specification, Form Submission forms - see `HTML Specification, Form Submission
@ -183,8 +183,8 @@ Explorer [#]_. ::
data = urllib.parse.urlencode(values) data = urllib.parse.urlencode(values)
data = data.encode('utf-8') data = data.encode('utf-8')
req = urllib.request.Request(url, data, headers) req = urllib.request.Request(url, data, headers)
response = urllib.request.urlopen(req) with urllib.request.urlopen(req) as response:
the_page = response.read() the_page = response.read()
The response also has two useful methods. See the section on `info and geturl`_ The response also has two useful methods. See the section on `info and geturl`_
which comes after we have a look at what happens when things go wrong. which comes after we have a look at what happens when things go wrong.

4
Doc/library/concurrent.futures.rst
View file

@ -138,8 +138,8 @@ ThreadPoolExecutor Example
# Retrieve a single page and report the url and contents # Retrieve a single page and report the url and contents
def load_url(url, timeout): def load_url(url, timeout):
conn = urllib.request.urlopen(url, timeout=timeout) with urllib.request.urlopen(url, timeout=timeout) as conn:
return conn.readall() return conn.read()
# We can use a with statement to ensure threads are cleaned up promptly # We can use a with statement to ensure threads are cleaned up promptly
with concurrent.futures.ThreadPoolExecutor(max_workers=5) as executor: with concurrent.futures.ThreadPoolExecutor(max_workers=5) as executor:

34
Doc/library/urllib.request.rst
View file

@ -1048,8 +1048,9 @@ This example gets the python.org main page and displays the first 300 bytes of
it. :: it. ::
>>> import urllib.request >>> import urllib.request
>>> f = urllib.request.urlopen('http://www.python.org/') >>> with urllib.request.urlopen('http://www.python.org/') as f:
>>> print(f.read(300)) ... print(f.read(300))
...
b'<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" b'<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">\n\n\n<html "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">\n\n\n<html
xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">\n\n<head>\n xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">\n\n<head>\n
@ -1091,8 +1092,9 @@ when the Python installation supports SSL. ::
>>> import urllib.request >>> import urllib.request
>>> req = urllib.request.Request(url='https://localhost/cgi-bin/test.cgi', >>> req = urllib.request.Request(url='https://localhost/cgi-bin/test.cgi',
... data=b'This data is passed to stdin of the CGI') ... data=b'This data is passed to stdin of the CGI')
>>> f = urllib.request.urlopen(req) >>> with urllib.request.urlopen(req) as f:
>>> print(f.read().decode('utf-8')) ... print(f.read().decode('utf-8'))
...
Got Data: "This data is passed to stdin of the CGI" Got Data: "This data is passed to stdin of the CGI"
The code for the sample CGI used in the above example is:: The code for the sample CGI used in the above example is::
@ -1107,7 +1109,8 @@ Here is an example of doing a ``PUT`` request using :class:`Request`::
import urllib.request import urllib.request
DATA=b'some data' DATA=b'some data'
req = urllib.request.Request(url='http://localhost:8080', data=DATA,method='PUT') req = urllib.request.Request(url='http://localhost:8080', data=DATA,method='PUT')
f = urllib.request.urlopen(req) with urllib.request.urlopen(req) as f:
pass
print(f.status) print(f.status)
print(f.reason) print(f.reason)
@ -1173,8 +1176,10 @@ containing parameters::
>>> import urllib.request >>> import urllib.request
>>> import urllib.parse >>> import urllib.parse
>>> params = urllib.parse.urlencode({'spam': 1, 'eggs': 2, 'bacon': 0}) >>> params = urllib.parse.urlencode({'spam': 1, 'eggs': 2, 'bacon': 0})
>>> f = urllib.request.urlopen("http://www.musi-cal.com/cgi-bin/query?%s" % params) >>> url = "http://www.musi-cal.com/cgi-bin/query?%s" % params
>>> print(f.read().decode('utf-8')) >>> with urllib.request.urlopen(url) as f:
... print(f.read().decode('utf-8'))
...
The following example uses the ``POST`` method instead. Note that params output The following example uses the ``POST`` method instead. Note that params output
from urlencode is encoded to bytes before it is sent to urlopen as data:: from urlencode is encoded to bytes before it is sent to urlopen as data::
@ -1186,8 +1191,9 @@ from urlencode is encoded to bytes before it is sent to urlopen as data::
>>> request = urllib.request.Request("http://requestb.in/xrbl82xr") >>> request = urllib.request.Request("http://requestb.in/xrbl82xr")
>>> # adding charset parameter to the Content-Type header. >>> # adding charset parameter to the Content-Type header.
>>> request.add_header("Content-Type","application/x-www-form-urlencoded;charset=utf-8") >>> request.add_header("Content-Type","application/x-www-form-urlencoded;charset=utf-8")
>>> f = urllib.request.urlopen(request, data) >>> with urllib.request.urlopen(request, data) as f:
>>> print(f.read().decode('utf-8')) ... print(f.read().decode('utf-8'))
...
The following example uses an explicitly specified HTTP proxy, overriding The following example uses an explicitly specified HTTP proxy, overriding
environment settings:: environment settings::
@ -1195,15 +1201,17 @@ environment settings::
>>> import urllib.request >>> import urllib.request
>>> proxies = {'http': 'http://proxy.example.com:8080/'} >>> proxies = {'http': 'http://proxy.example.com:8080/'}
>>> opener = urllib.request.FancyURLopener(proxies) >>> opener = urllib.request.FancyURLopener(proxies)
>>> f = opener.open("http://www.python.org") >>> with opener.open("http://www.python.org") as f:
>>> f.read().decode('utf-8') ... f.read().decode('utf-8')
...
The following example uses no proxies at all, overriding environment settings:: The following example uses no proxies at all, overriding environment settings::
>>> import urllib.request >>> import urllib.request
>>> opener = urllib.request.FancyURLopener({}) >>> opener = urllib.request.FancyURLopener({})
>>> f = opener.open("http://www.python.org/") >>> with opener.open("http://www.python.org/") as f:
>>> f.read().decode('utf-8') ... f.read().decode('utf-8')
...
Legacy interface Legacy interface

9
Doc/tutorial/stdlib.rst
View file

@ -153,10 +153,11 @@ protocols. Two of the simplest are :mod:`urllib.request` for retrieving data
from URLs and :mod:`smtplib` for sending mail:: from URLs and :mod:`smtplib` for sending mail::
>>> from urllib.request import urlopen >>> from urllib.request import urlopen
>>> for line in urlopen('http://tycho.usno.navy.mil/cgi-bin/timer.pl'): >>> with urlopen('http://tycho.usno.navy.mil/cgi-bin/timer.pl') as response:
... line = line.decode('utf-8') # Decoding the binary data to text. ... for line in response:
... if 'EST' in line or 'EDT' in line: # look for Eastern Time ... line = line.decode('utf-8') # Decoding the binary data to text.
... print(line) ... if 'EST' in line or 'EDT' in line: # look for Eastern Time
... print(line)
<BR>Nov. 25, 09:43:32 PM EST <BR>Nov. 25, 09:43:32 PM EST