Refactor Profile to allow lazy initialization

This changes also allows us to use Profile class in more situations,
which makes the code better.

instaloader/instaloader.py

@@ -135,30 +135,8 @@ class Instaloader:
     def __exit__(self, *args):
         self.close()
 
-    def get_username_by_id(self, profile_id: int) -> str:
-        """To get the current username of a profile, given its unique ID, this function can be used."""
-        data = self.context.graphql_query("472f257a40c653c64c666ce877d59d2b",
-                                          {'id': str(profile_id), 'first': 1})['data']['user']
-        if data:
-            data = data["edge_owner_to_timeline_media"]
-        else:
-            raise ProfileNotExistsException("No profile found, the user may have blocked you (ID: " +
-                                            str(profile_id) + ").")
-        if not data['edges']:
-            if data['count'] == 0:
-                raise ProfileHasNoPicsException("Profile with ID {0}: no pics found.".format(str(profile_id)))
-            else:
-                raise LoginRequiredException("Login required to determine username (ID: " + str(profile_id) + ").")
-        else:
-            return Post.from_mediaid(self.context, int(data['edges'][0]["node"]["id"])).owner_username
-
-    def get_id_by_username(self, profile: str) -> int:
-        """Each Instagram profile has its own unique ID which stays unmodified even if a user changes
-        his/her username. To get said ID, given the profile's name, you may call this function."""
-        return Profile(self.context, profile).userid
-
     @_requires_login
-    def get_followers(self, profile: str) -> Iterator[Dict[str, Any]]:
+    def get_followers(self, profile: Profile) -> Iterator[Dict[str, Any]]:
         """
         Retrieve list of followers of given profile.
         To use this, one needs to be logged in and private profiles has to be followed,
@@ -167,12 +145,12 @@ class Instaloader:
         :param profile: Name of profile to lookup followers.
         """
         yield from self.context.graphql_node_list("37479f2b8209594dde7facb0d904896a",
-                                                  {'id': str(self.get_id_by_username(profile))},
-                                                  'https://www.instagram.com/' + profile + '/',
+                                                  {'id': str(profile.userid)},
+                                                  'https://www.instagram.com/' + profile.username + '/',
                                                   lambda d: d['data']['user']['edge_followed_by'])
 
     @_requires_login
-    def get_followees(self, profile: str) -> Iterator[Dict[str, Any]]:
+    def get_followees(self, profile: Profile) -> Iterator[Dict[str, Any]]:
         """
         Retrieve list of followees (followings) of given profile.
         To use this, one needs to be logged in and private profiles has to be followed,
@@ -181,8 +159,8 @@ class Instaloader:
         :param profile: Name of profile to lookup followers.
         """
         yield from self.context.graphql_node_list("58712303d941c6855d4e888c5f0cd22f",
-                                                  {'id': str(self.get_id_by_username(profile))},
-                                                  'https://www.instagram.com/' + profile + '/',
+                                                  {'id': str(profile.userid)},
+                                                  'https://www.instagram.com/' + profile.username + '/',
                                                   lambda d: d['data']['user']['edge_follow'])
 
     def download_pic(self, filename: str, url: str, mtime: datetime,
@@ -608,7 +586,7 @@ class Instaloader:
         """
         self.context.log("Retrieving saved posts...")
         count = 1
-        for post in Profile(self.context, self.context.username).get_saved_posts():
+        for post in Profile.from_username(self.context, self.context.username).get_saved_posts():
             if max_count is not None and count > max_count:
                 break
             name = post.owner_username
@@ -671,15 +649,17 @@ class Instaloader:
                 if fast_update and not downloaded:
                     break
 
-    def check_profile_id(self, profile_name: str, profile: Optional[Profile] = None) -> str:
+    def check_profile_id(self, profile_name: str) -> Profile:
         """
         Consult locally stored ID of profile with given name, check whether ID matches and whether name
         has changed and return current name of the profile, and store ID of profile.
 
         :param profile_name: Profile name
-        :param profile: The :class:`Profile`, or None if the profile was not found
-        :return: current profile name, profile id
+        :return: Instance of current profile
         """
+        profile = None
+        with suppress(ProfileNotExistsException):
+            profile = Profile.from_username(self.context, profile_name)
         profile_exists = profile is not None
         if ((format_string_contains_key(self.dirname_pattern, 'profile') or
              format_string_contains_key(self.dirname_pattern, 'target'))):
@@ -698,7 +678,8 @@ class Instaloader:
                 else:
                     self.context.log("Trying to find profile {0} using its unique ID {1}.".format(profile_name,
                                                                                                   profile_id))
-                newname = self.get_username_by_id(profile_id)
+                profile_from_id = Profile.from_id(self.context, profile_id)
+                newname = profile_from_id.username
                 self.context.log("Profile {0} has changed its name to {1}.".format(profile_name, newname))
                 if ((format_string_contains_key(self.dirname_pattern, 'profile') or
                      format_string_contains_key(self.dirname_pattern, 'target'))):
@@ -709,8 +690,8 @@ class Instaloader:
                 else:
                     os.rename('{0}/{1}_id'.format(self.dirname_pattern.format(), profile_name.lower()),
                               '{0}/{1}_id'.format(self.dirname_pattern.format(), newname.lower()))
-                return newname
-            return profile_name
+                return profile_from_id
+            return profile
         except FileNotFoundError:
             pass
         if profile_exists:
@@ -719,7 +700,7 @@ class Instaloader:
             with open(id_filename, 'w') as text_file:
                 text_file.write(str(profile.userid) + "\n")
                 self.context.log("Stored ID {0} for profile {1}.".format(profile.userid, profile_name))
-            return profile_name
+            return profile
         raise ProfileNotExistsException("Profile {0} does not exist.".format(profile_name))
 
     def download_profile(self, profile_name: str,
@@ -728,21 +709,13 @@ class Instaloader:
                          download_stories: bool = False, download_stories_only: bool = False,
                          filter_func: Optional[Callable[[Post], bool]] = None) -> None:
         """Download one profile"""
-        profile_name = profile_name.lower()
 
         # Get profile main page json
-        profile = None
-        with suppress(ProfileNotExistsException):
-            # ProfileNotExistsException is raised again later in check_profile_id() when we search the profile, so we
-            # must suppress it here.
-            profile = Profile(self.context, profile_name)
-
         # check if profile does exist or name has changed since last download
         # and update name and json data if necessary
-        name_updated = self.check_profile_id(profile_name, profile)
-        if name_updated != profile_name:
-            profile_name = name_updated
-            profile = Profile(self.context, profile_name)
+        profile = self.check_profile_id(profile_name.lower())
+
+        profile_name = profile.username
 
         if self.context.is_logged_in and profile.has_blocked_viewer and not profile.is_private:
             # raising ProfileNotExistsException invokes "trying again anonymously" logic

instaloader/structures.py

@@ -43,6 +43,7 @@ class Post:
         :param node: Node structure, as returned by Instagram.
         :param owner_profile: The Profile of the owner, if already known at creation.
         """
+        assert 'shortcode' in node
         self._context = context
         self._node = node
         self._owner_profile = owner_profile
@@ -105,25 +106,25 @@ class Post:
                 d = d[key]
             return d
 
+    @property
+    def owner_profile(self) -> 'Profile':
+        if not self._owner_profile:
+            owner_struct = self._field('owner')
+            if 'username' in owner_struct:
+                self._owner_profile = Profile(self._context, owner_struct)
+            else:
+                self._owner_profile = Profile.from_id(self._context, owner_struct['id'])
+        return self._owner_profile
+
     @property
     def owner_username(self) -> str:
-        """The Post's lowercase owner name, or 'UNKNOWN'."""
-        try:
-            if self._owner_profile:
-                return self._owner_profile.username.lower()
-            return self._field('owner', 'username').lower()
-        except (InstaloaderException, KeyError, TypeError) as err:
-            if self._context.raise_all_errors:
-                raise err
-            self._context.error("Get owner name of {}: {} -- using \'UNKNOWN\'.".format(self, err))
-            return 'UNKNOWN'
+        """The Post's lowercase owner name."""
+        return self.owner_profile.username
 
     @property
     def owner_id(self) -> int:
         """The ID of the Post's owner."""
-        if self._owner_profile:
-            return self._owner_profile.userid
-        return int(self._field('owner', 'id'))
+        return self.owner_profile.userid
 
     @property
     def date_local(self) -> datetime:
@@ -288,28 +289,62 @@ class Profile:
 
     This class implements == and is hashable.
     """
-    def __init__(self, context: InstaloaderContext, profile_name: str):
-        """
-        Lookup Profile information and create Profile instance.
-
-        :param context: :class:`InstaloaderContext` instance used for queries etc.
-        :param identifier: Profile name (string).
-        """
+    def __init__(self, context: InstaloaderContext, node: Dict[str, Any]):
+        assert 'username' in node
         self._context = context
+        self._node = node
 
+    @classmethod
+    def from_username(cls, context: InstaloaderContext, username: str):
+        # pylint:disable=protected-access
+        profile = cls(context, {'username': username.lower()})
+        profile._obtain_metadata()  # to raise ProfileNotExistException now in case username is invalid
+        return profile
+
+    @classmethod
+    def from_id(cls, context: InstaloaderContext, profile_id: int):
+        data = context.graphql_query("472f257a40c653c64c666ce877d59d2b",
+                                     {'id': str(profile_id), 'first': 1})['data']['user']
+        if data:
+            data = data["edge_owner_to_timeline_media"]
+        else:
+            raise ProfileNotExistsException("No profile found, the user may have blocked you (ID: " +
+                                            str(profile_id) + ").")
+        if not data['edges']:
+            if data['count'] == 0:
+                raise ProfileHasNoPicsException("Profile with ID {0}: no pics found.".format(str(profile_id)))
+            else:
+                raise LoginRequiredException("Login required to determine username (ID: " + str(profile_id) + ").")
+        username = Post.from_mediaid(context, int(data['edges'][0]["node"]["id"])).owner_username
+        return cls(context, {'username': username.lower(), 'id': profile_id})
+
+    def _obtain_metadata(self):
         try:
-            metadata = self._context.get_json('{}/'.format(profile_name), params={'__a': 1})
-            self._metadata = metadata['graphql'] if 'graphql' in metadata else metadata
+            metadata = self._context.get_json('{}/'.format(self.username), params={'__a': 1})
+            self._node = metadata['graphql']['user'] if 'graphql' in metadata else metadata['user']
         except QueryReturnedNotFoundException:
-            raise ProfileNotExistsException('Profile {} does not exist.'.format(profile_name))
+            raise ProfileNotExistsException('Profile {} does not exist.'.format(self.username))
+
+    def _metadata(self, *keys) -> Any:
+        try:
+            d = self._node
+            for key in keys:
+                d = d[key]
+            return d
+        except KeyError:
+            self._obtain_metadata()
+            d = self._node
+            for key in keys:
+                d = d[key]
+            return d
 
     @property
     def userid(self) -> int:
-        return int(self._metadata['user']['id'])
+        return int(self._metadata('id'))
 
     @property
     def username(self) -> str:
-        return self._metadata['user']['username']
+        return self._metadata('username').lower()
 
     def __repr__(self):
         return '<Profile {} ({})>'.format(self.username, self.userid)
@@ -324,50 +359,47 @@ class Profile:
 
     @property
     def is_private(self) -> bool:
-        return self._metadata['user']['is_private']
+        return self._metadata('is_private')
 
     @property
     def followed_by_viewer(self) -> bool:
-        return self._metadata['user']['followed_by_viewer']
+        return self._metadata('followed_by_viewer')
 
     @property
     def mediacount(self) -> int:
-        if "media" in self._metadata["user"]:
-            # backwards compatibility with old non-graphql structure
-            return self._metadata["user"]["media"]["count"]
-        return self._metadata["user"]["edge_owner_to_timeline_media"]["count"]
+        return self._metadata('edge_owner_to_timeline_media', 'count')
 
     @property
     def biography(self) -> str:
-        return self._metadata['user']['biography']
+        return self._metadata('biography')
 
     @property
     def blocked_by_viewer(self) -> bool:
-        return self._metadata['user']['blocked_by_viewer']
+        return self._metadata('blocked_by_viewer')
 
     @property
     def follows_viewer(self) -> bool:
-        return self._metadata['user']['follows_viewer']
+        return self._metadata('follows_viewer')
 
     @property
     def full_name(self) -> str:
-        return self._metadata['user']['full_name']
+        return self._metadata('full_name')
 
     @property
     def has_blocked_viewer(self) -> bool:
-        return self._metadata['user']['has_blocked_viewer']
+        return self._metadata('has_blocked_viewer')
 
     @property
     def has_requested_viewer(self) -> bool:
-        return self._metadata['user']['has_requested_viewer']
+        return self._metadata('has_requested_viewer')
 
     @property
     def is_verified(self) -> bool:
-        return self._metadata['user']['is_verified']
+        return self._metadata('is_verified')
 
     @property
     def requested_by_viewer(self) -> bool:
-        return self._metadata['user']['requested_by_viewer']
+        return self._metadata('requested_by_viewer')
 
     def get_profile_pic_url(self) -> str:
         """Return URL of profile picture"""
@@ -378,22 +410,14 @@ class Profile:
             return data["user"]["hd_profile_pic_url_info"]["url"]
         except (InstaloaderException, KeyError) as err:
             self._context.error('{} Unable to fetch high quality profile pic.'.format(err))
-            return self._metadata["user"]["profile_pic_url_hd"] if "profile_pic_url_hd" in self._metadata["user"] \
-                else self._metadata["user"]["profile_pic_url"]
+            return self._metadata("profile_pic_url_hd")
 
     def get_posts(self) -> Iterator[Post]:
         """Retrieve all posts from a profile."""
-        if 'media' in self._metadata['user']:
-            # backwards compatibility with old non-graphql structure
-            yield from (Post(self._context, node, owner_profile=self)
-                        for node in self._metadata['user']['media']['nodes'])
-            has_next_page = self._metadata['user']['media']['page_info']['has_next_page']
-            end_cursor = self._metadata['user']['media']['page_info']['end_cursor']
-        else:
-            yield from (Post(self._context, edge['node'], owner_profile=self)
-                        for edge in self._metadata['user']['edge_owner_to_timeline_media']['edges'])
-            has_next_page = self._metadata['user']['edge_owner_to_timeline_media']['page_info']['has_next_page']
-            end_cursor = self._metadata['user']['edge_owner_to_timeline_media']['page_info']['end_cursor']
+        yield from (Post(self._context, edge['node'], owner_profile=self)
+                    for edge in self._metadata('edge_owner_to_timeline_media', 'edges'))
+        has_next_page = self._metadata('edge_owner_to_timeline_media', 'page_info', 'has_next_page')
+        end_cursor = self._metadata('edge_owner_to_timeline_media', 'page_info', 'end_cursor')
         while has_next_page:
             # We do not use self.graphql_node_list() here, because profile_metadata
             # lets us obtain the first 12 nodes 'for free'
@@ -414,23 +438,18 @@ class Profile:
         if self.username != self._context.username:
             raise LoginRequiredException("--login={} required to get that profile's saved posts.".format(self.username))
 
-        data = self._metadata
-
-        while True:
-            if "edge_saved_media" in data["user"]:
-                is_edge = True
-                saved_media = data["user"]["edge_saved_media"]
-            else:
-                is_edge = False
-                saved_media = data["user"]["saved_media"]
-
-            if is_edge:
-                yield from (Post(self._context, edge["node"]) for edge in saved_media["edges"])
-            else:
-                yield from (Post(self._context, node) for node in saved_media["nodes"])
-
-            if not saved_media["page_info"]["has_next_page"]:
-                break
+        yield from (Post(self._context, edge['node'])
+                    for edge in self._metadata('edge_saved_media', 'edges'))
+        has_next_page = self._metadata('edge_saved_media', 'page_info', 'has_next_page')
+        end_cursor = self._metadata('edge_saved_media', 'page_info', 'end_cursor')
+        while has_next_page:
             data = self._context.graphql_query("f883d95537fbcd400f466f63d42bd8a1",
-                                               {'id': self.userid, 'first': GRAPHQL_PAGE_LENGTH,
-                                                'after': saved_media["page_info"]["end_cursor"]})['data']
+                                               {'id': self.userid,
+                                                'first': GRAPHQL_PAGE_LENGTH,
+                                                'after': end_cursor},
+                                               'https://www.instagram.com/{0}/'.format(self.username))
+            media = data['data']['user']['edge_saved_media']
+            yield from (Post(self._context, edge['node'])
+                        for edge in media['edges'])
+            has_next_page = media['page_info']['has_next_page']
+            end_cursor = media['page_info']['end_cursor']

test/instaloader-unittests.py

@@ -71,7 +71,7 @@ class TestInstaloader(unittest.TestCase):
 
     def test_saved_paging(self):
         self.L.load_session_from_file(OWN_USERNAME)
-        for count, post in enumerate(instaloader.Profile(self.L.context, OWN_USERNAME).get_saved_posts()):
+        for count, post in enumerate(instaloader.Profile.from_username(self.L.context, OWN_USERNAME).get_saved_posts()):
             print(post)
             if count == PAGING_MAX_COUNT:
                 break
@@ -82,29 +82,31 @@ class TestInstaloader(unittest.TestCase):
 
     def test_get_followees(self):
         self.L.load_session_from_file(OWN_USERNAME)
-        for f in self.L.get_followees(OWN_USERNAME):
+        for f in self.L.get_followees(instaloader.Profile.from_username(self.L.context, OWN_USERNAME)):
             print(f['username'])
 
     def test_get_followers(self):
         self.L.load_session_from_file(OWN_USERNAME)
-        for f in self.L.get_followers(OWN_USERNAME):
+        for f in self.L.get_followers(instaloader.Profile.from_username(self.L.context, OWN_USERNAME)):
             print(f['username'])
 
     def test_get_username_by_id(self):
-        self.assertEqual(PUBLIC_PROFILE.lower(), self.L.get_username_by_id(PUBLIC_PROFILE_ID))
+        self.assertEqual(PUBLIC_PROFILE.lower(),
+                         instaloader.Profile.from_id(self.L.context, PUBLIC_PROFILE_ID).username)
 
     def test_get_id_by_username(self):
-        self.assertEqual(PUBLIC_PROFILE_ID, self.L.get_id_by_username(PUBLIC_PROFILE))
+        self.assertEqual(PUBLIC_PROFILE_ID,
+                         instaloader.Profile.from_username(self.L.context, PUBLIC_PROFILE).userid)
 
     def test_get_likes(self):
         self.L.load_session_from_file(OWN_USERNAME)
-        for post in instaloader.Profile(self.L.context, OWN_USERNAME).get_posts():
+        for post in instaloader.Profile.from_username(self.L.context, OWN_USERNAME).get_posts():
             for like in post.get_likes():
                 print(like['username'])
             break
 
     def test_post_from_mediaid(self):
-        for post in instaloader.Profile(self.L.context, PUBLIC_PROFILE).get_posts():
+        for post in instaloader.Profile.from_username(self.L.context, PUBLIC_PROFILE).get_posts():
             post2 = instaloader.Post.from_mediaid(self.L.context, post.mediaid)
             self.assertEqual(post, post2)
             break