refactored pagination behaviour in 'paginate' decorator

lastfm/decorators.py

@@ -4,6 +4,7 @@
 __author__ = "Abhinav Sarkar <abhinav@abhinavsarkar.net>"
 __version__ = "0.2"
 __license__ = "GNU Lesser General Public License"
+__package__ = "lastfm"
 
 def top_property(list_property_name):
     """
@@ -95,6 +96,26 @@ def authenticate(func):
                 pass
         raise AuthenticationFailedError(
             "user '%s' does not have permissions to access the service" % username)
+    wrapper.__doc__ = func.__doc__
+    return wrapper
+
+def depaginate(func):
+    from lastfm.lazylist import lazylist
+    def wrapper(*args, **kwargs):
+        @lazylist
+        def generator(lst):
+            gen = func(*args, **kwargs)
+            total_pages = gen.next()
+            for e in gen:
+                yield e
+            for page in xrange(2, total_pages+1):
+                kwargs['page'] = page
+                gen = func(*args, **kwargs)
+                gen.next()
+                for e in gen:
+                    yield e
+        return generator()
+    wrapper.__doc__ = func.__doc__
     return wrapper
 
 import copy

lastfm/geo.py

@@ -8,17 +8,18 @@ __package__ = "lastfm"
 
 from lastfm.base import LastfmBase
 from lastfm.mixins import Cacheable
-from lastfm.lazylist import lazylist
+from lastfm.decorators import cached_property, top_property, depaginate
-from lastfm.decorators import cached_property, top_property
 
 class Geo(object):
     """A class representing an geographic location"""
     @staticmethod
+    @depaginate
     def get_events(api,
                   location,
                   latitude = None,
                   longitude = None,
-                  distance = None):
+                  distance = None,
+                  page = None):
         """
         Get the events for a location.
         
@@ -52,27 +53,16 @@ class Geo(object):
 
         if latitude is not None and longitude is not None:
             params.update({'lat': latitude, 'long': longitude})
+        if page is not None:
+            params.update({'page': page})
             
-        @lazylist
-        def gen(lst):
         data = api._fetch_data(params).find('events')
         total_pages = int(data.attrib['totalpages'])
+        yield total_pages
         
-            @lazylist
-            def gen2(lst, data):
         for e in data.findall('event'):
             yield Event.create_from_data(api, e)
 
-            for e in gen2(data):
-                yield e
-
-            for page in xrange(2, total_pages+1):
-                params.update({'page': page})
-                data = api._fetch_data(params).find('events')
-                for e in gen2(data):
-                    yield e
-        return gen()
-
     @staticmethod
     def get_top_artists(api, country):
         """

lastfm/group.py

@@ -9,7 +9,7 @@ __package__ = "lastfm"
 from lastfm.base import LastfmBase
 from lastfm.mixins import Cacheable
 from lastfm.lazylist import lazylist
-from lastfm.decorators import cached_property, top_property
+from lastfm.decorators import cached_property, top_property, depaginate
 
 class Group(LastfmBase, Cacheable):
     """A class representing a group on last.fm."""
@@ -194,20 +194,18 @@ class Group(LastfmBase, Cacheable):
         return gen()
 
     @cached_property
-    def members(self):
+    @depaginate
+    def members(self, page = None):
         """
         members of the group
         @rtype: L{lazylist} of L{User}
         """
         params = self._default_params({'method': 'group.getMembers'})
-        
+        if page is not None:
-        @lazylist
+            params.update({'page': page})
-        def gen(lst):
         data = self._api._fetch_data(params).find('members')
         total_pages = int(data.attrib['totalPages'])
-
+        yield total_pages
-            @lazylist
-            def gen2(lst, data):
         for u in data.findall('user'):
             yield User(
                 self._api,
@@ -217,16 +215,6 @@ class Group(LastfmBase, Cacheable):
                 url = u.findtext('url')
             )
         
-            for u in gen2(data):
-                yield u
-
-            for page in xrange(1, total_pages+1):
-                params.update({'page': page})
-                data = self._api._fetch_data(params).find('members')
-                for u in gen2(data):
-                    yield u
-        return gen()
-        
     def _default_params(self, extra_params = {}):
         if not self.name:
             raise InvalidParametersError("group has to be provided.")

lastfm/mixins/searchable.py

@@ -5,14 +5,16 @@ __version__ = "0.2"
 __license__ = "GNU Lesser General Public License"
 __package__ = "lastfm.mixins"
 
-from lastfm.lazylist import lazylist
+from lastfm.decorators import depaginate
 
 class Searchable(object):
     @classmethod
+    @depaginate
     def search(cls,
                api,
                search_item,
                limit = None,
+               page = None,
                **kwds):
         from lastfm.api import Api
         cls_name = cls.__name__.lower()
@@ -26,28 +28,16 @@ class Searchable(object):
 
         if limit:
             params.update({'limit': limit})
+        if page is not None:
+            params.update({'page': page})
         
-        @lazylist
-        def gen(lst):
         data = api._fetch_data(params).find('results')
         total_pages = int(data.findtext("{%s}totalResults" % Api.SEARCH_XMLNS))/ \
                             int(data.findtext("{%s}itemsPerPage" % Api.SEARCH_XMLNS)) + 1
-
+        yield total_pages
-            @lazylist
-            def gen2(lst, data):
         for a in data.findall('%smatches/%s'%(cls_name, cls_name)):
             yield cls._search_yield_func(api, a)
 
-            for a in gen2(data):
-                yield a
-
-            for page in xrange(2, total_pages+1):
-                params.update({'page': page})
-                data = api._fetch_data(params).find('results')
-                for a in gen2(data):
-                    yield a
-        return gen()
-
     @staticmethod
     def _search_yield_func(api, search_term):
         pass

lastfm/user.py

@@ -9,7 +9,7 @@ from lastfm.base import LastfmBase
 from lastfm.mixins import Cacheable, Shoutable
 from lastfm.lazylist import lazylist
 import lastfm.playlist
-from lastfm.decorators import cached_property, top_property, authenticate
+from lastfm.decorators import cached_property, top_property, authenticate, depaginate
 
 class User(LastfmBase, Cacheable, Shoutable):
     """A class representing an user."""
@@ -111,61 +111,37 @@ class User(LastfmBase, Cacheable, Shoutable):
                 for e in data.findall('event')
                 ]
         
-    def get_past_events(self,
+    @depaginate
-                      limit = None):
+    def get_past_events(self, limit = None, page = None):
         params = self._default_params({'method': 'user.getPastEvents'})
         if limit is not None:
             params.update({'limit': limit})
+        if page is not None:
+            params.update({'page': page})
 
-        @lazylist
-        def gen(lst):
         data = self._api._fetch_data(params).find('events')
         total_pages = int(data.attrib['totalPages'])
-
+        yield total_pages
-            @lazylist
-            def gen2(lst, data):
         for e in data.findall('event'):
             yield Event.create_from_data(self._api, e)
 
-            for e in gen2(data):
-                yield e
-
-            for page in xrange(2, total_pages+1):
-                params.update({'page': page})
-                data = self._api._fetch_data(params).find('events')
-                for e in gen2(data):
-                    yield e
-        return gen()
-
     @cached_property
     def past_events(self):
         return self.get_past_events()
     
     @authenticate
-    def get_recommended_events(self, limit = None):
+    @depaginate
+    def get_recommended_events(self, limit = None, page = None):
         params = {'method': 'user.getRecommendedEvents'}
         if limit is not None:
             params.update({'limit': limit})
-
+        if page is not None:
-        @lazylist
-        def gen(lst):
-            data = self._api._fetch_data(params, sign = True, session = True).find('events')
-            total_pages = int(data.attrib['totalPages'])
-
-            @lazylist
-            def gen2(lst, data):
-                for e in data.findall('event'):
-                    yield Event.create_from_data(self._api, e)
-
-            for e in gen2(data):
-                yield e
-
-            for page in xrange(2, total_pages+1):
             params.update({'page': page})
         data = self._api._fetch_data(params, sign = True, session = True).find('events')
-                for e in gen2(data):
+        total_pages = int(data.attrib['totalPages'])
-                    yield e
+        yield total_pages
-        return gen()
+        for e in data.findall('event'):
+            yield Event.create_from_data(self._api, e)
 
     @cached_property
     def recommended_events(self):
@@ -411,16 +387,16 @@ class User(LastfmBase, Cacheable, Shoutable):
     
     @cached_property
     @authenticate
-    def recommended_artists(self):
+    @depaginate
+    def recommended_artists(self, page = None):
         params = {'method': 'user.getRecommendedArtists'}
+        if page is not None:
+            params.update({'page': page})
             
-        @lazylist
-        def gen(lst):
         data = self._api._fetch_data(params, sign = True, session = True).find('recommendations')
         total_pages = int(data.attrib['totalPages'])
+        yield total_pages
 
-            @lazylist
-            def gen2(lst, data):
         for a in data.findall('artist'):
             yield Artist(
                          self._api,
@@ -431,16 +407,6 @@ class User(LastfmBase, Cacheable, Shoutable):
                          image = dict([(i.get('size'), i.text) for i in a.findall('image')]),
                          )
     
-            for a in gen2(data):
-                yield a
-
-            for page in xrange(2, total_pages+1):
-                params.update({'page': page})
-                data = self._api._fetch_data(params, sign = True, session = True).find('recommendations')
-                for a in gen2(data):
-                    yield a
-        return gen()
-    
     def get_top_tracks(self, period = None):
         params = self._default_params({'method': 'user.getTopTracks'})
         if period is not None:
@@ -755,19 +721,19 @@ class User(LastfmBase, Cacheable, Shoutable):
         def user(self):
             return self._user
 
-        def get_albums(self,
+        @depaginate
-                      limit = None):
+        def get_albums(self, limit = None, page = None):
             params = self._default_params({'method': 'library.getAlbums'})
             if limit is not None:
                 params.update({'limit': limit})
+            if page is not None:
+                params.update({'page': page})
 
-            @lazylist
+            try:
-            def gen(lst):
                 data = self._api._fetch_data(params).find('albums')            
                 total_pages = int(data.attrib['totalPages'])
+                yield total_pages
     
-                @lazylist
-                def gen2(lst, data):
                 for a in data.findall('album'):
                     yield Album(
                                 self._api,
@@ -788,20 +754,8 @@ class User(LastfmBase, Cacheable, Shoutable):
                                               playcount = int(a.findtext('playcount')),
                                               )
                                 )
-
-
-                for a in gen2(data):
-                    yield a
-
-                for page in xrange(2, total_pages+1):
-                    params.update({'page': page})
-                    try:
-                        data = self._api._fetch_data(params).find('albums')
             except LastfmError:
-                        continue
+                return
-                    for a in gen2(data):
-                        yield a
-            return gen()
 
         @cached_property
         def albums(self):
@@ -825,19 +779,19 @@ class User(LastfmBase, Cacheable, Shoutable):
             self._api._post_data(params)
             self._albums = None
             
-        def get_artists(self,
+        @depaginate
-                       limit = None):
+        def get_artists(self, limit = None, page = None):
             params = self._default_params({'method': 'library.getArtists'})
             if limit is not None:
                 params.update({'limit': limit})
+            if page is not None:
+                params.update({'page': page})
 
-            @lazylist
+            try:
-            def gen(lst):
                 data = self._api._fetch_data(params).find('artists')
                 total_pages = int(data.attrib['totalPages'])
+                yield total_pages
                 
-                @lazylist
-                def gen2(lst, data):
                 for a in data.findall('artist'):
                     yield Artist(
                                  self._api,
@@ -853,19 +807,8 @@ class User(LastfmBase, Cacheable, Shoutable):
                                  streamable = (a.findtext('streamable') == "1"),
                                  image = dict([(i.get('size'), i.text) for i in a.findall('image')]),
                                  )
-
-                for a in gen2(data):
-                    yield a
-
-                for page in xrange(2, total_pages+1):
-                    params.update({'page': page})
-                    try:
-                        data = self._api._fetch_data(params).find('artists')
             except LastfmError:
-                        continue
+                return
-                    for a in gen2(data):
-                        yield a
-            return gen()
 
         @cached_property
         def artists(self):
@@ -881,19 +824,19 @@ class User(LastfmBase, Cacheable, Shoutable):
             self._api._post_data(params)
             self._artists = None
 
-        def get_tracks(self,
+        @depaginate
-                      limit = None):
+        def get_tracks(self, limit = None, page = None):
             params = self._default_params({'method': 'library.getTracks'})
             if limit is not None:
                 params.update({'limit': limit})
+            if page is not None:
+                params.update({'page': page})
             
-            @lazylist
+            try:
-            def gen(lst):
                 data = self._api._fetch_data(params).find('tracks')
                 total_pages = int(data.attrib['totalPages'])
+                yield total_pages
                 
-                @lazylist
-                def gen2(lst, data):
                 for t in data.findall('track'):
                     yield Track(
                                 self._api,
@@ -916,20 +859,8 @@ class User(LastfmBase, Cacheable, Shoutable):
                                 full_track = (t.find('streamable').attrib['fulltrack'] == '1'),
                                 image = dict([(i.get('size'), i.text) for i in t.findall('image')]),
                                 )
-
-                for t in gen2(data):
-                    yield t
-
-                for page in xrange(2, total_pages+1):
-                    params.update({'page': page})
-                    data = None
-                    try:
-                        data = self._api._fetch_data(params).find('tracks')
             except LastfmError:
-                        continue
+                return
-                    for t in gen2(data):
-                        yield t
-            return gen()
 
         @cached_property
         def tracks(self):

lastfm/venue.py

@@ -7,8 +7,7 @@ __package__ = "lastfm"
 
 from lastfm.base import LastfmBase
 from lastfm.mixins import Cacheable, Searchable
-from lastfm.lazylist import lazylist
+from lastfm.decorators import cached_property, depaginate
-from lastfm.decorators import cached_property
 
 class Venue(LastfmBase, Cacheable, Searchable):
     """A class representing a venue of an event"""
@@ -57,32 +56,21 @@ class Venue(LastfmBase, Cacheable, Searchable):
                 for e in data.findall('event')
                 ]
         
-    def get_past_events(self,
+    @depaginate
-                      limit = None):
+    def get_past_events(self, limit = None, page = None):
         params = self._default_params({'method': 'venue.getPastEvents'})
         if limit is not None:
             params.update({'limit': limit})
+        if page is not None:
+            params.update({'page': page})
 
-        @lazylist
-        def gen(lst):
         data = self._api._fetch_data(params).find('events')
         total_pages = int(data.attrib['totalPages'])
+        yield total_pages
 
-            @lazylist
-            def gen2(lst, data):
         for e in data.findall('event'):
             yield Event.create_from_data(self._api, e)
 
-            for e in gen2(data):
-                yield e
-
-            for page in xrange(2, total_pages+1):
-                params.update({'page': page})
-                data = self._api._fetch_data(params).find('events')
-                for e in gen2(data):
-                    yield e
-        return gen()
-
     @cached_property
     def past_events(self):
         return self.get_past_events()
@@ -96,6 +84,9 @@ class Venue(LastfmBase, Cacheable, Searchable):
     
     @staticmethod
     def _search_yield_func(api, venue):
+        latitude = venue.findtext('location/{%s}point/{%s}lat' % ((Location.XMLNS,)*2))
+        longitude = venue.findtext('location/{%s}point/{%s}long' % ((Location.XMLNS,)*2))
+        
         return Venue(
                      api,
                      id = int(venue.findtext('id')),
@@ -109,12 +100,8 @@ class Venue(LastfmBase, Cacheable, Searchable):
                                             ),
                                          street = venue.findtext('location/street'),
                                          postal_code = venue.findtext('location/postalcode'),
-                                         latitude = float(venue.findtext(
+                                         latitude = (latitude.strip()!= '') and float(latitude) or None,
-                                             'location/{%s}point/{%s}lat' % ((Location.XMLNS,)*2)
+                                         longitude = (longitude.strip()!= '') and float(longitude) or None,
-                                             )),
-                                         longitude = float(venue.findtext(
-                                             'location/{%s}point/{%s}long' % ((Location.XMLNS,)*2)
-                                             )),
                                        ),
                      url = venue.findtext('url')
                      )