Google Hacks 2Nd Edition [Electronic resources] نسخه متنی

Hack 98. Program Google in Python

Programming the Google Web API with Python is
simple and clean, as these scripts and interactive examples
demonstrate .

Programming to the Google Web API from Python is a piece of
cake, thanks to Mark Pilgrim's
PyGoogle wrapper module (http://pygoogle.sourceforge.net/)now
maintained by Brian Landers. PyGoogle abstracts away much of the
underlying SOAP, XML, and request/response layers, leaving you free
to spend your time with the data itself.

9.15.1. PyGoogle Installation

Download a copy of PyGoogle (http://sourceforge.net/project/showfiles.php?group_id=99616)
and follow the installation instructions (http://pygoogle.sourceforge.net/dist/readme.txt).
Assuming all goes to plan, this should be nothing more complex than:

% python setup.py install Alternatively, if you want to give this a whirl without installing
PyGoogle or don't have permissions to install it
globally on your system, simply put the included
SOAP.py and google.py files
into the same directory as the googly.py script
itself.

9.15.2. The Code

Save this code to a text file called googly.py.
Be sure to replace insert key
here with your own Google API key.

#!/usr/bin/python
# googly.py
# A typical Google Web API Python script using Mark Pilgrim's
# PyGoogle Google Web API wrapper
# [http://diveintomark.org/projects/pygoogle/].
# Usage: python googly.py <query>
import sys, string, codecs
# Use the PyGoogle module.
import google
# Grab the query from the command line
if sys.argv[1:]:
query = sys.argv[1]
else:
sys.exit('Usage: python googly.py <query>')
# Your Google API developer's key.
google.LICENSE_KEY = 'insert key here'
# Query Google.
data = google.doGoogleSearch(query)
# Teach standard output to deal with utf-8 encoding in the results.
sys.stdout = codecs.lookup('utf-8')[-1](sys.stdout)
# Output.
for result in data.results:
print string.join( (result.title, result.URL, result.snippet), "\n"), "\n"

9.15.3. Running the Hack

Invoke the script on the command line ["How to Run
the Hacks" in the Preface] as follows:

% python googly.py " query words "

9.15.4. The Results

Here's a sample run, searching for
"learning python":

% python googly.py "learning python"
oreilly.com -- Online Catalog: <b>Learning</b>
<b>Python</b>
http://www.oreilly.com/catalog/lpython/
<b>Learning</b> <b>Python</b> is an
introduction to the increasingly popular interpreted programming
language that's portable, powerful, and remarkably easy to use in both
<b>...</b>
...
Book Review: <b>Learning</b> <b>Python</b>
http://www2.linuxjournal.com/lj-issues/issue66/3541l
<b>...</b> Issue 66: Book Review: <b>Learning</b>
<b>Python</b> <b>...</b> Enter
<b>Learning</b> <b>Python</b>. My executive summary
is that this is the right book for me and probably for many others
as well. <b>...</b>

9.15.5. Hacking the Hack

Python has a marvelous interface for working interactively with the
interpreter. It's a good place to experiment with
modules such as PyGoogle, querying the Google API on the fly and
digging through the data structures it returns.

Here's a sample interactive PyGoogle session
demonstrating the use of the doGoogleSearch,
doGetCachedPage, and
doSpellingSuggestion functions:

% python
Python 2.2 (#1, 07/14/02, 23:25:09)
[GCC Apple cpp-precomp 6.14] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import google
>>> google.LICENSE_KEY = ' insert key here
'
>>> data = google.doGoogleSearch("Learning Python")
>>> dir(data.meta)
['_ _doc_ _', '_ _init_ _', '_ _module_ _', 'directoryCategories',
'documentFiltering', 'endIndex', 'estimateIsExact',
'estimatedTotalResultsCount', 'searchComments', 'searchQuery',
'searchTime', 'searchTips', 'startIndex']
>>> data.meta.estimatedTotalResultsCount
115000
>>> data.meta.directoryCategories
[{u'specialEncoding': '', u'fullViewableName': "Top/Business/Industries/
Publishing/Publishers/Nonfiction/Business/O'Reilly_and_Associates/
Technical_Books/Python"}]
>>> dir(data.results[5])
['URL', '_ _doc_ _', '_ _init_ _', '_ _module_ _', 'cachedSize',
'directoryCategory', 'directoryTitle', 'hostName',
'relatedInformationPresent', 'snippet', 'summary', 'title']
>>> data.results[0].title
'oreilly.com -- Online Catalog: <b>Learning</b> <b>Python'
>>> data.results[0].URL
'http://www.oreilly.com/catalog/lpython/'
>>> google.doGetCachedPage(data.results[0].URL)
'<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">\n
<BASE HREF="http://www.oreilly.com/catalog/lpython/"><table border=1
...
>>> google.doSpellingSuggestion('lurn piethon' )
'learn python'