Use sha256 for stamp number to avoid collisions

src/collections.py

@@ -283,13 +283,18 @@ def get_featured_collections_feed(base_dir: str,
 
 def store_feature_authorization(base_dir: str, nickname: str, domain: str,
                                 featured_item: {}) -> bool:
-    """Stores a feature authorization
+    """Stores a feature authorization after receiving a request for a
+    particular actor or hashtag
     """
+    if not featured_item.get('featureAuthorization'):
+        return False
+    if not isinstance(featured_item['featureAuthorization'], str):
+        return False
     accounts_dir: str = acct_dir(base_dir, nickname, domain)
     if not is_a_dir(accounts_dir + '/stamps'):
         makedir(accounts_dir + '/stamps')
-    stamp_id = featured_item['featureAuthorization'].split('/')[1]
-    feature_authorization_filename = accounts_dir + '/' + stamp_id
+    stamp_id = url_text_to_number(featured_item['featureAuthorization'])
+    feature_authorization_filename = accounts_dir + '/stamps/' + stamp_id
     if not is_a_file(feature_authorization_filename):
         return False
     return save_json(featured_item, feature_authorization_filename)

src/utils.py

@@ -17,6 +17,7 @@ import datetime
 import json
 import locale
 import idna
+import base64
 from cryptography.hazmat.backends import default_backend
 from cryptography.hazmat.primitives import hashes
 from src.followingCalendar import add_person_to_calendar
@@ -58,8 +59,6 @@ INVALID_ACTOR_URL_CHARACTERS = (
     ';', '='
 )
 
-URL_TEXT_MAGIC_NUMBER = 7439
-
 
 def is_account_dir(dir_name: str) -> bool:
     """Is the given directory an account within /accounts ?
@@ -4381,14 +4380,5 @@ def get_preferred_username(actor: {}, system_language: str) -> str:
 def url_text_to_number(url: str) -> str:
     """converts url text or collection name to a number string used as an id
     """
-    result = ''
-    for char in url:
-        num = ord(char)
-        if num > 99:
-            continue
-        if num > 9:
-            result = str(num) + result
-        else:
-            result = '0' + str(num) + result
-    num = (URL_TEXT_MAGIC_NUMBER + int(result)) % 9999999999999999999999999999
-    return str(num)
+    hash_result = get_sha_256(url)
+    return base64.b64encode(hash_result).decode('utf-8')