Support for new target :saved

If logged in, Instaloader is now able to download posts which are marked
as saved. This feature was suggested in #78.

instaloader.py

@@ -22,7 +22,7 @@ from datetime import datetime
 from enum import Enum
 
 from io import BytesIO
-from typing import Any, Callable, Dict, Iterator, List, Optional, Tuple
+from typing import Any, Callable, Dict, Iterator, List, Optional, Tuple, Union
 
 import requests
 import requests.utils
@@ -651,12 +651,12 @@ class Instaloader:
         session.headers.update(self._default_http_header(empty_session_only=True))
         return session
 
-    def graphql_query(self, query_id: int, variables: Dict[str, Any],
+    def graphql_query(self, query_identifier: Union[int, str], variables: Dict[str, Any],
                       referer: Optional[str] = None) -> Dict[str, Any]:
         """
         Do a GraphQL Query.
 
-        :param query_id: Query ID.
+        :param query_identifier: Query ID or Hash.
         :param variables: Variables for the Query.
         :param referer: HTTP Referer, or None.
         :return: The server's response dictionary.
@@ -670,8 +670,9 @@ class Instaloader:
         tmpsession.headers['accept'] = '*/*'
         if referer is not None:
             tmpsession.headers['referer'] = urllib.parse.quote(referer)
-        resp_json = self.get_json('graphql/query', params={'query_id': query_id,
-                                                           'variables': json.dumps(variables, separators=(',', ':'))},
+        resp_json = self.get_json('graphql/query',
+                                  params={'query_id' if isinstance(query_identifier, int) else 'query_hash': query_identifier,
+                                          'variables': json.dumps(variables, separators=(',', ':'))},
                                   session=tmpsession)
         if 'status' not in resp_json:
             self.error("GraphQL response did not contain a \"status\" field.")
@@ -1214,6 +1215,56 @@ class Instaloader:
                 if fast_update and not downloaded:
                     break
 
+    def get_saved_posts(self) -> Iterator[Post]:
+        """Get Posts that are marked as saved by the user."""
+
+        data = self.get_profile_metadata(self.username)
+        user_id = data["user"]["id"]
+
+        while True:
+            if "graphql" in data:
+                is_edge = True
+                saved_media = data["graphql"]["user"]["edge_saved_media"]
+            elif "data" in data:
+                is_edge = True
+                saved_media = data["data"]["user"]["edge_saved_media"]
+            else:
+                is_edge = False
+                saved_media = data["user"]["saved_media"]
+
+            if is_edge:
+                yield from (Post(self, edge["node"]) for edge in saved_media["edges"])
+            else:
+                yield from (Post(self, node) for node in saved_media["nodes"])
+
+            if not saved_media["page_info"]["has_next_page"]:
+                break
+            data = self.graphql_query("f883d95537fbcd400f466f63d42bd8a1",
+                                      {'id': user_id, 'first': 200, 'after': saved_media["page_info"]["end_cursor"]})
+
+    def download_saved_posts(self, max_count: int = None, fast_update: bool = False,
+                             filter_func: Optional[Callable[[Post], bool]] = None) -> None:
+        """Download user's saved pictures.
+
+        :param max_count: Maximum count of pictures to download
+        :param fast_update: If true, abort when first already-downloaded picture is encountered
+        :param filter_func: function(post), which returns True if given picture should be downloaded
+        """
+        count = 1
+        for post in self.get_saved_posts():
+            if max_count is not None and count > max_count:
+                break
+            name = post.owner_username
+            if filter_func is not None and not filter_func(post):
+                self._log("<pic by {} skipped".format(name), flush=True)
+                continue
+            self._log("[{:>3}] {} ".format(count, name), end=str(), flush=True)
+            count += 1
+            with self._error_catcher('Download saved posts'):
+                downloaded = self.download_post(post, target=':saved')
+                if fast_update and not downloaded:
+                    break
+
     def get_hashtag_posts(self, hashtag: str) -> Iterator[Post]:
         """Get Posts associated with a #hashtag."""
         yield from (Post(self, node) for node in
@@ -1471,6 +1522,14 @@ class Instaloader:
                             self.download_stories(fast_update=fast_update)
                     else:
                         self.error("--login=USERNAME required to download {}.".format(pentry))
+                elif pentry == ":saved":
+                    if username is not None:
+                        self._log("Retrieving saved posts...")
+                        with self._error_catcher():
+                            self.download_saved_posts(fast_update=fast_update, max_count=max_count,
+                                                      filter_func=filter_func)
+                    else:
+                        self.error("--login=USERNAME required to download {}.".format(pentry))
                 else:
                     targets.add(pentry)
             if len(targets) > 1: