While we can manually send and receive data over HTTP using the socket library, there is a much simpler way to perform this common task in Python by using the
urllib, you can treat a web page much like a file. You simply indicate which web page you would like to retrieve and
urllib handles all of the HTTP protocol and header details.
The equivalent code to read the
romeo.txt file from the web using
urllib is as follows:
%%python3 import urllib.request fhand = urllib.request.urlopen('http://data.pr4e.org/romeo.txt') for line in fhand: print(line.decode().strip()) # Code: http://www.py4e.com/code3/urllib1.py
Once the web page has been opened with
urllib.urlopen, we can treat it like a file and read through it using a
When the program runs, we only see the output of the contents of the file. The headers are still sent, but the
urllib code consumes the headers and only returns the data to us.
But soft what light through yonder window breaks It is the east and Juliet is the sun Arise fair sun and kill the envious moon Who is already sick and pale with grief
As an example, we can write a program to retrieve the data for
romeo.txt and compute the frequency of each word in the file as follows:
%%python3 import urllib.request, urllib.parse, urllib.error fhand = urllib.request.urlopen('http://data.pr4e.org/romeo.txt') counts = dict() for line in fhand: words = line.decode().split() for word in words: counts[word] = counts.get(word, 0) + 1 print(counts) # Code: http://www.py4e.com/code3/urlwords.py
Again, once we have opened the web page, we can read it like a local file.