Google Hacks 2Nd Edition [Electronic resources] نسخه متنی

Hack 80. Program Gmail

Try your hand at writing an alternative
interface to Gmail using the freely available Python, Perl, PHP,
Java, and .NET libraries and API frameworks .

The relatively simple and
lightweight data interface to Gmail stems from the separation between
user interface (client-side JavaScript) and data model. This has
spawned myriad frontends (graphical and otherwise), libraries, and
unofficial "API" implementations in
Python, Perl, PHP, Java, and .NET.

For a glimpse of the Gmail engine and protocol underlying the
official Gmail interface and the lion's share of the
unofficial APIs and libraries written to the service, take a gander
at Johnvey

Hwang's
"About the Gmail engine and
protocol" (http://johnvey.com/features/gmailapi/; scroll
down).

Programmatic access to Gmail is accomplished by screen-scraping either the web interface or its underlying data format. While the data format is pretty simple and isn't expected to change dramatically, there's no telling what Google might do that could adversely affect the various programmatic interfaces to their service. Thus, it goes without saying that such hackery comes with no quality of service guarantee. In other words, expect breakages. And if you do notice something's gone wrong, visit the home page of your chosen programmatic interface for the latest version of the code, news, and further information.

6.13.1. Python

(http://libgmail.sourceforge.net; GNU Public
License 2.0/PSF) Python binding for Gmail provides a nice, clean
interface (as you'd expect from Python) to your
Gmail account.

Libgmail bundles a lovely set of useful example applications, usable
right out of the box:

archive.py
Downloads your Gmail messages to your computer for archiving,
importing, or moving purposes.

gmailsmtp.py
Proxies SMTP requests, allowing you to use Gmail to send email from
the comfort of your preferred email application; a related script,
sendmsg.py, sends a single email message via
Gmail from the command linenot unlike using the Unix
mail command.

gmailpopd.py
Proxies a standard POP interface to mail from your preferred email
application.

gmailftpd.py
Pretends to be an FTP server, allowing you to download (only)
messages labeled "ftp" via a
standard FTP application.

6.13.1.1 Installing the hack

Installation is just a matter of downloading and unpacking the
library (http://sourceforge.net/project/showfiles.php?group_id=113492,
or click the Downloads link on the libgmail home page) and putting it
someplace findable by Python.

6.13.1.2 The code

Libgmail sports much functionality, each with its own rather
self-explanatory function name:
getMessagesByQuery,
getQuotaInfo, getLabelNames,
getMessagesByLabel,
getrawMessage, and
getUnreadMsgCount. Leaf through
libgmail.py for the kind of details only a
programmer could love.

Here's a snippet of sample code showing off login,
folder selection, and strolling through emailthread by thread,
message by message:

#!/usr/bin/python
# libgmail_example.py
# A simple example of the libgmail Python binding for Gmail in action
# http://libgmail.sourceforge.net/
#
# Usage: python gmail_in_python.py
import libgmail
# Login
gmail = libgmail.GmailAccount('raelity@gmail.com', '12bucklemyshoe')
gmail.login( )
# Select a folder, label, or starred messages--in this case, the Inbox
folder = gmail.getMessagesByFolder('inbox')
# Stroll through threads in the Inbox
for thread in folder:
print thread.id, len(thread), thread.subject
# Stroll through messages in each thread
for msg in thread:
print " ", msg.id, msg.number, msg.subject Replace raelity@gmail.com and
12bucklemyshoe with your Gmail email
address and password. Instead of inbox,
you can use any of Gmail's standard folder names or
your custom labelse.g., starred,
sent, or
friends.

Save the code to a file called
gmail_in_python.py.

6.13.1.3 Running the hack

Run the gmail_in_python.py script on the command
line, like so:

$ python libgmail_example.pl
WARNING:root:Live Javascript and constants file versions differ.
ff602fe48d89bc3 1 Hello from Hotmail
ff602fe48d89bc3 1 Hello from Hotmail
ff5fb9c2829c165 1 Hello Gmail via Gmail Loader
ff5fb9c2829c165 1 Hello Gmail via Gmail Loader
ff5691f7170cb62 1 Hello Gmail via Gmail Loader
ff5691f7170cb62 1 Hello Gmail via Gmail Loader
ff3f4310237b607 1 Howdy gmail-lite
ff3f4310237b607 1 Howdy gmail-lite

6.13.1.4 Hacking the hack

Swap in a call to getMessagesByQuery and you now
have a command line right to the Gmail search engine:

#folder = gmail.getMessagesByFolder('inbox')
folder = gmail.getMessagesByQuery('from:rael subject:Howdy') Here are the results of this little switch:

$ python libgmail_example.pl
WARNING:root:Live Javascript and constants file versions differ.
ff3f4310237b607 1 Howdy gmail-lite
ff3f4310237b607 1 Howdy gmail-lite

6.13.1.5 See also

gmail.py (http://www.holovaty.com/blog/archive/2004/06/18/1751)
is a simple Python interface to Gmail, focusing on exporting raw
messages for backup and import.

6.13.2. Perl

Mail::Webmail::Gmail (http://search.cpan.org/~mincus/Mail-Webmail-Gmail-1.00/lib/Mail/Webmail/Gmail.pm)
provides

Perl hackers a programmatic interface to
Gmail. You'll find full POD documentation and more
sample code than you can shake a stick it in the module and online at
the aforementioned URL.

A Comprehensive Perl Archive Network (CPAN) search for gmail
(http://search.cpan.org/search?query=gmail&mode=all)
at the time of this writing finds three more Perl
Gmail libraries:

Mail::Webmail::Gmail ,
WWW::GMail , and
WWW::Scraper::Gmail .

6.13.3. PHP

GMailer or libgmailer (http://gmail-lite.sourceforge.net; GNU Public
License) is a PHP

library for interacting with Gmail by way of the curl library
(http://www.php.net/curl) with
SSL support (http://www.openssl.org). It is the engine
underlying gmail-lite Hack #76 , an
HTML-only interface to Gmail.

For full libgmailer documentation and plenty of sample code, leaf
through the online documentation (http://gmail-lite.sourceforge.net/docsl).

6.13.4. Java

G4j or
GMail API for

Java (http://g4j.sourceforge.net; GNU Public
License) is a Java interface to Gmail. The API comes with GMailer for
Java, a basic GUI frontend to Gmail built on top of G4j.

Full documentation in Javadoc HTML is available online (http://g4j.sourceforge.net/doc).

6.13.5. .NET

(http://johnvey.com/features/gmailapi; GNU
Public License) is a .NET foundation for programming to Gmail. A full
package of source for the API itself; the Gmail Agent Applet, a proof
of concept Windows frontend to Gmail; and associated Windows
Installer projects are available for download.

There's also full documentation available in both
HTML format (http://johnvey.com/features/gmailapi/docs)
and as Windows Help.