[kupfer] shorten_links: Rework all, use only shorteners with API

[Ulrik Sverdrup <usverdrup src gnome org>]

commit a13ed2846c724c746562baa3868a5816f2dd36bd
Author: Ulrik Sverdrup <ulrik sverdrup gmail com>
Date:   Tue Mar 1 03:21:28 2011 +0100

    shorten_links: Rework all, use only shorteners with API
    
    Fix Bit.ly to use their API (with a registered API key). Add Is.gd url
    shortening service.
    
    Remove shorl.com and Ur1.ca since they don't provide an API. We can't
    use web scraping since it might break at any time.
    
    Also use OperationError for direct & user-visible error reporting on
    HTTP errors etc.

 kupfer/plugin/shorten_links.py |  107 +++++++++++++++------------------------
 1 files changed, 41 insertions(+), 66 deletions(-)
---
diff --git a/kupfer/plugin/shorten_links.py b/kupfer/plugin/shorten_links.py
index 8440a5e..ec5bad4 100644
--- a/kupfer/plugin/shorten_links.py
+++ b/kupfer/plugin/shorten_links.py
@@ -2,24 +2,15 @@
 __kupfer_name__ = _("Shorten Links")
 __kupfer_actions__ = ("ShortenLinks", )
 __description__ = _("Create short aliases of long URLs")
-__version__ = "2009-12-24"
+__version__ = "2011-03-01"
 __author__ = "Karol BÄ?dkowski <karol bedkowski gmail com>"
 
-import re
 import httplib
 import urllib
 
-from kupfer.objects import Leaf, Action, Source, UrlLeaf
+from kupfer.objects import Leaf, Action, Source, UrlLeaf, OperationError
 from kupfer import pretty
 
-
-_HEADER = {
-		'Content-type':'application/x-www-form-urlencoded',
-		'Accept': 'text/xml,application/xml,application/xhtml+xml,text/html',
-		'Accept-charset': 'utf-8;q=0.7'
-}
-
-
 class _ShortLinksService(Leaf):
 	def __init__(self, name):
 		Leaf.__init__(self, name, name)
@@ -30,87 +21,69 @@ class _GETService(_ShortLinksService, pretty.OutputMixin):
 	""" A unified shortener service working with GET requests """
 	host = None
 	path = None
-	result_regex = None
+	url_key = "url"
 
 	def process(self, url):
-		query_string = urllib.urlencode({"url": url})
+		"""Shorten @url or raise ValueError"""
+		query_string = urllib.urlencode({self.url_key : url})
 		try:
 			conn = httplib.HTTPConnection(self.host)
 			conn.request("GET", self.path+query_string)
 			resp = conn.getresponse()
 			if resp.status != 200:
-				raise ValueError('invalid response %d, %s' % (resp.status,
+				raise ValueError('Invalid response %d, %s' % (resp.status,
 					resp.reason))
 			
 			result = resp.read()
-			if self.result_regex is not None:
-				resurl = re.findall(self.result_regex, result)
-				if resurl:
-					return resurl[0]
-			else:
-				return result
-
-		except (httplib.HTTPException, ValueError), err:
-			self.output_error(type(err), err)
+			return result.strip()
+
+		except (httplib.HTTPException, ValueError) as exc:
+			raise ValueError(exc)
 		return _('Error')
 
 
+# NOTE: It's important that we use only sites that provide a stable API
+
 class TinyUrl(_GETService):
+	"""
+	Website: http://tinyurl.com
+	"""
 	host = "tinyurl.com"
 	path = "/api-create.php?"
 
 	def __init__(self):
 		_ShortLinksService.__init__(self, u'TinyUrl.com')
 
-class Shorl(_GETService):
-	host = 'shorl.com'
-	path = '/create.php?'
-	result_regex = r'Shorl: \<a href=".+?" rel="nofollow">(.+?)</a>'
+class IsGd(_GETService):
+	"""
+	Website: http://is.gd
+	Reference: http://is.gd/apishorteningreference.php
+	"""
+	host = 'is.gd'
+	path = '/create.php?format=simple&'
 
 	def __init__(self):
-		_ShortLinksService.__init__(self, u'Shorl.com')
+		_ShortLinksService.__init__(self, u'Is.gd')
 
 class BitLy(_GETService):
+	"""
+	Website: http://bit.ly
+	Reference: http://code.google.com/p/bitly-api/wiki/ApiDocumentation
+	"""
+	# No password is available for this login name,
+	# yet there is a possibility that you could track
+	# all URLs shortened using this API key
+	BITLY_LOGIN = "kupferkupfer"
+	BITLY_API_KEY = "R_a617770f00b647d6c22ce162105125c2"
+
 	host = 'bit.ly'
-	path = '/?'
-	result_regex = r'\<input id="shortened-url" value="(.+?)" \/\>'
+	path = ('http://api.bitly.com/v3/shorten?login=%s&apiKey=%s&format=txt&;' %
+			(BITLY_LOGIN, BITLY_API_KEY))
+	url_key = "longUrl"
 
 	def __init__(self):
 		_ShortLinksService.__init__(self, u'Bit.ly')
 
-UR1CA_HOST='ur1.ca'
-UR1CA_PATH=''
-UR1CA_RESULT_RE = re.compile(r'\<p class="success">.+?<a href=".+?">(.+?)</a></p>')
-
-class Ur1Ca(_ShortLinksService):
-	""" Shorten urls with Ur1.ca """
-	def __init__(self):
-		_ShortLinksService.__init__(self, u'Ur1.ca')
-
-	def process(self, url):
-		if not (url.startswith('http://') or url.startswith('https://') or 
-				url.startswith('mailto:')):
-			url = 'http://' + url
-		query_param = urllib.urlencode(dict(longurl=url, submit='Make it an ur1!'))
-		try:
-			conn = httplib.HTTPConnection(UR1CA_HOST)
-			#conn.debuglevel=255
-			conn.request("POST", UR1CA_PATH, query_param, _HEADER)
-			resp = conn.getresponse()
-			if resp.status != 200:
-				raise ValueError('invalid response %d, %s' % (resp.status,
-					resp.reason))
-			
-			result = resp.read()
-			resurl = UR1CA_RESULT_RE.findall(result)
-			if resurl:
-				return resurl[0]
-			return _('Error')
-
-		except (httplib.HTTPException, ValueError), err:
-			pretty.print_error(__name__, 'TinyUrl.process error', type(err), err)
-		return _('Error')
-
 
 class ShortenLinks(Action):
 	''' Shorten links with selected engine '''
@@ -122,7 +95,10 @@ class ShortenLinks(Action):
 		return True
 
 	def activate(self, leaf, iobj):
-		result = iobj.process(leaf.object)
+		try:
+			result = iobj.process(leaf.object)
+		except ValueError as exc:
+			raise OperationError(unicode(exc))
 		return UrlLeaf(result, result)
 
 	def item_types(self):
@@ -147,8 +123,7 @@ class ServicesSource(Source):
 
 	def get_items(self):
 		yield TinyUrl()
-		yield Shorl()
-		yield Ur1Ca()
+		yield IsGd()
 		yield BitLy()
 
 	def should_sort_lexically(self):