Making fetching of covers more robust and also create command line interface for it.

setup.py

@@ -38,6 +38,7 @@ entry_points = {
                              'any2lrf   = libprs500.ebooks.lrf.any.convert_from:main',
                              'lrf2lrs   = libprs500.ebooks.lrf.parser:main',
                              'isbndb    = libprs500.ebooks.metadata.isbndb:main',
+                             'librarything = libprs500.ebooks.metadata.library_thing:main',
                              'lrf2html  = libprs500.ebooks.lrf.html.convert_to:main',                             
                            ], 
         'gui_scripts'    : [ 

src/libprs500/ebooks/metadata/library_thing.py

@@ -0,0 +1,104 @@
+##    Copyright (C) 2008 Kovid Goyal kovid@kovidgoyal.net
+##    This program is free software; you can redistribute it and/or modify
+##    it under the terms of the GNU General Public License as published by
+##    the Free Software Foundation; either version 2 of the License, or
+##    (at your option) any later version.
+##
+##    This program is distributed in the hope that it will be useful,
+##    but WITHOUT ANY WARRANTY; without even the implied warranty of
+##    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+##    GNU General Public License for more details.
+##
+##    You should have received a copy of the GNU General Public License along
+##    with this program; if not, write to the Free Software Foundation, Inc.,
+##    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+'''
+Fetch cover from LibraryThing.com based on ISBN number.
+'''
+
+import sys, socket, os
+from optparse import OptionParser
+
+from libprs500 import browser as _browser, __author__, __appname__, __version__
+from libprs500.ebooks.BeautifulSoup import BeautifulSoup 
+browser = None
+
+class LibraryThingError(Exception):
+    pass
+
+class ISBNNotFound(LibraryThingError):
+    pass
+
+class ServerBusy(LibraryThingError):
+    pass
+
+def login(username, password, force=True):
+    global browser
+    if browser is not None and not force:
+        return
+    browser = _browser()
+    browser.open('http://www.librarything.com')
+    browser.select_form('signup')
+    browser['formusername'] = username
+    browser['formpassword'] = password
+    browser.submit()
+    
+
+def cover_from_isbn(isbn, timeout=5.):
+    global browser
+    if browser is None:
+        browser = _browser()
+    _timeout = socket.getdefaulttimeout()
+    socket.setdefaulttimeout(timeout)                
+    try:
+        src = browser.open('http://www.librarything.com/isbn/'+isbn).read()
+        s = BeautifulSoup(src)
+        url = s.find('td', attrs={'class':'left'})
+        if url is None:
+            if s.find('div', attrs={'class':'highloadwarning'}) is not None:
+                raise ServerBusy(_('Could not fetch cover as server is experiencing high load. Please try again later.'))
+            raise ISBNNotFound('ISBN: '+isbn+_(' not found.'))
+        url = url.find('img')
+        if url is None:
+            raise LibraryThingError(_('Server error. Try again later.'))
+        url = url['src']
+        cover_data = browser.open(url).read()
+        return cover_data, url.rpartition('.')[-1]
+    finally:
+        socket.setdefaulttimeout(_timeout)
+
+def option_parser():
+    parser = OptionParser(epilog='Created by '+__author__, 
+                          version=__appname__+' '+__version__,
+                          usage=\
+'''
+%prog [options] ISBN
+
+Fetch a cover image for the book identified by ISBN from LibraryThing.com
+''')
+    parser.add_option('-u', '--username', default=None, 
+                      help='Username for LibraryThing.com')
+    parser.add_option('-p', '--password', default=None, 
+                      help='Password for LibraryThing.com')
+    return parser
+
+def main(args=sys.argv):
+    parser = option_parser()
+    opts, args = parser.parse_args(args)
+    if len(args) != 2:
+        parser.print_help()
+        return 1
+    isbn = args[1]
+    if opts.username and opts.password:
+        login(opts.username, opts.password)
+        
+    cover_data, ext = cover_from_isbn(isbn)
+    if not ext:
+        ext = 'jpg'
+    oname = os.path.abspath(isbn+'.'+ext)
+    open(oname, 'w').write(cover_data)
+    print 'Cover saved to file', oname
+    return 0
+
+if __name__ == '__main__':
+    sys.exit(main())

src/libprs500/gui2/dialogs/metadata_single.py

@@ -16,7 +16,7 @@
 The dialog used to edit meta information for a book as well as 
 add/remove formats
 '''
-import os, urllib, socket
+import os
 
 from PyQt4.QtCore import SIGNAL, QObject, QCoreApplication, Qt
 from PyQt4.QtGui import QPixmap, QListWidgetItem, QErrorMessage, QDialog
@@ -27,8 +27,9 @@ from libprs500.gui2 import qstring_to_unicode, error_dialog, file_icon_provider,
 from libprs500.gui2.dialogs.metadata_single_ui import Ui_MetadataSingleDialog
 from libprs500.gui2.dialogs.fetch_metadata import FetchMetadata
 from libprs500.gui2.dialogs.tag_editor import TagEditor
-from libprs500.ebooks.BeautifulSoup import BeautifulSoup
+from libprs500.gui2.dialogs.password import PasswordDialog
 from libprs500.ebooks import BOOK_EXTENSIONS
+from libprs500.ebooks.metadata.library_thing import login, cover_from_isbn, LibraryThingError
 
 class Format(QListWidgetItem):
     def __init__(self, parent, ext, path=None):
@@ -215,38 +216,32 @@ class MetadataSingleDialog(QDialog, Ui_MetadataSingleDialog):
     def fetch_cover(self):
         isbn   = qstring_to_unicode(self.isbn.text())
         if isbn:
+            d = PasswordDialog(self, 'LibraryThing account', 
+                               _('<p>Enter your username and password for <b>LibraryThing.com</b>. <br/>If you do not have one, you can <a href=\'http://www.librarything.com\'>register</a> for free!.</p>'))
+            if not d.username() or not d.password():
+                d.exec_()
+                if d.result() != PasswordDialog.Accepted:
+                    return
             self.fetch_cover_button.setEnabled(False)
             self.setCursor(Qt.WaitCursor)
             QCoreApplication.instance().processEvents()
-            timeout = socket.getdefaulttimeout()
-            socket.setdefaulttimeout(5.)                
             try:
-                src = urllib.urlopen('http://www.librarything.com/isbn/'+isbn).read()
-                s = BeautifulSoup(src)
-                url = s.find('td', attrs={'class':'left'})
-                if url is None:
-                    if s.find('div', attrs={'class':'highloadwarning'}) is not None:
-                        raise Exception('Could not fetch cover as server is experiencing high load. Please try again later.')
-                    raise Exception('ISBN: '+isbn+' not found.')
-                url = url.find('img')
-                if url is None:
-                    raise Exception('Server error. Try again later.')
-                url = url['src']
-                cover = urllib.urlopen(url).read()
+                login(d.username(), d.password(), force=False)
+                cover_data = cover_from_isbn(isbn)[0]
+            
                 pix = QPixmap()
-                pix.loadFromData(cover)
+                pix.loadFromData(cover_data)
                 if pix.isNull():
-                    error_dialog(self.window, url + " is not a valid picture").exec_()
+                    error_dialog(self.window, "The cover is not a valid picture").exec_()
                 else:
                     self.cover.setPixmap(pix)
                     self.cover_changed = True
                     self.cpixmap = pix   
-            except Exception, err:
+            except LibraryThingError, err:
                 error_dialog(self, _('Could not fetch cover'), _('<b>Could not fetch cover.</b><br/>')+str(err)).exec_()
             finally:
                 self.fetch_cover_button.setEnabled(True)
                 self.unsetCursor()
-                socket.setdefaulttimeout(timeout)
                 
         else:
             error_dialog(self, _('Cannot fetch cover'), _('You must specify the ISBN identifier for this book.')).exec_()