Various minor fixes

* Fix Post.owner_profile in cases where initial owner struct contains id
  only

* Assert node structure is complete enough at Post creation

* Fix get_followees() call in _main()

* Prefer importing from '.' rather than '.<submodule>' in __main__

* Fix name of instaloader_unittests ('-' is illegal in module names)

* Foreport 5fe2a70374
  "Fix downloading of hashtags"

* Foreport 67ac8f3397
  "Enforce being logged in for getting username by id"

instaloader/__main__.py

@@ -6,11 +6,10 @@ import sys
 from argparse import ArgumentParser, SUPPRESS
 from typing import Callable, List, Optional
 
-from . import __version__
-from .exceptions import *
-from .instaloader import Instaloader, Tristate, get_default_session_filename
+from . import (Instaloader, InstaloaderException, InvalidArgumentException, Post, Profile, ProfileNotExistsException,
+               Tristate, __version__)
+from .instaloader import get_default_session_filename
 from .instaloadercontext import default_user_agent
-from .structures import Post
 
 
 def usage_string():
@@ -92,7 +91,8 @@ def _main(instaloader: Instaloader, targetlist: List[str],
             with instaloader.context.error_catcher(target):
                 if target[0] == '@':
                     instaloader.context.log("Retrieving followees of %s..." % target[1:])
-                    profiles.update([followee['username'] for followee in instaloader.get_followees(target[1:])])
+                    followees = instaloader.get_followees(Profile.from_username(instaloader.context, target[1:]))
+                    profiles.update([followee['username'] for followee in followees])
                 elif target[0] == '#':
                     instaloader.download_hashtag(hashtag=target[1:], max_count=max_count, fast_update=fast_update,
                                                  filter_func=filter_func)

instaloader/instaloader.py

@@ -607,12 +607,18 @@ class Instaloader:
 
     def get_hashtag_posts(self, hashtag: str) -> Iterator[Post]:
         """Get Posts associated with a #hashtag."""
-        yield from (Post(self.context, node)
-                    for node in self.context.graphql_node_list("298b92c8d7cad703f7565aa892ede943",
-                                                               {'tag_name': hashtag},
-                                                               'https://www.instagram.com/explore/tags/{0}/'
-                                                               .format(hashtag),
-                                                               lambda d: d['data']['hashtag']['edge_hashtag_to_media']))
+        has_next_page = True
+        end_cursor = None
+        while has_next_page:
+            if end_cursor:
+                params = {'__a': 1, 'max_id': end_cursor}
+            else:
+                params = {'__a': 1}
+            hashtag_data = self.context.get_json('explore/tags/{0}/'.format(hashtag),
+                                                 params)['graphql']['hashtag']['edge_hashtag_to_media']
+            yield from (Post(self.context, edge['node']) for edge in hashtag_data['edges'])
+            has_next_page = hashtag_data['page_info']['has_next_page']
+            end_cursor = hashtag_data['page_info']['end_cursor']
 
     def download_hashtag(self, hashtag: str,
                          max_count: Optional[int] = None,
@@ -675,6 +681,10 @@ class Instaloader:
                 else:
                     self.context.log("Trying to find profile {0} using its unique ID {1}.".format(profile_name,
                                                                                                   profile_id))
+                if not self.context.is_logged_in:
+                    self.context.error("Profile {} changed its name. "
+                                       "If you use --login=USERNAME, I can find out the new name.")
+                    raise LoginRequiredException("--login=USERNAME required to obtain profile name from its ID number")
                 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))

instaloader/structures.py

@@ -43,7 +43,15 @@ 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
+
+        # Ensure node contains all the data that is accessed via self._node
+        assert 'shortcode' in node or 'code' in node
+        assert 'id' in node
+        assert 'owner' in node
+        assert 'date' in node or 'taken_at_timestamp' in node
+        assert 'display_url' in node or 'display_src' in node
+        assert 'is_video' in node
+
         self._context = context
         self._node = node
         self._owner_profile = owner_profile
@@ -109,10 +117,18 @@ class Post:
     @property
     def owner_profile(self) -> 'Profile':
         if not self._owner_profile:
-            owner_struct = self._field('owner')
+            if 'username' in self._node['owner']:
+                owner_struct = self._node['owner']
+            else:
+                # Sometimes, the 'owner' structure does not contain the username, only the user's ID.  In that case,
+                # this call triggers downloading of the complete Post metadata struct, where the owner username
+                # is contained. This is better than to get the username by user ID, since it is possible anonymously
+                # and gives us other information that is more likely to be usable.
+                owner_struct = self._full_metadata['owner']
             if 'username' in owner_struct:
                 self._owner_profile = Profile(self._context, owner_struct)
             else:
+                # Fallback, if we still did not get the owner username
                 self._owner_profile = Profile.from_id(self._context, owner_struct['id'])
         return self._owner_profile
 
@@ -303,6 +319,8 @@ class Profile:
 
     @classmethod
     def from_id(cls, context: InstaloaderContext, profile_id: int):
+        if not context.is_logged_in:
+            raise LoginRequiredException("--login=USERNAME required to obtain profile metadata from its ID number.")
         data = context.graphql_query("472f257a40c653c64c666ce877d59d2b",
                                      {'id': str(profile_id), 'first': 1})['data']['user']
         if data:

test/instaloader_unittests.py

@@ -91,6 +91,7 @@ class TestInstaloader(unittest.TestCase):
             print(f['username'])
 
     def test_get_username_by_id(self):
+        self.L.load_session_from_file(OWN_USERNAME)
         self.assertEqual(PUBLIC_PROFILE.lower(),
                          instaloader.Profile.from_id(self.L.context, PUBLIC_PROFILE_ID).username)