Ensure that groups can't follow groups, to prevent circular reference

follow.py

@@ -29,6 +29,7 @@ from utils import isAccountDir
 from utils import getUserPaths
 from utils import acctDir
 from utils import hasGroupType
+from utils import isGroupAccount
 from acceptreject import createAccept
 from acceptreject import createReject
 from webfinger import webfingerHandle
@@ -750,6 +751,9 @@ def receiveFollowRequest(session, baseDir: str, httpPrefix: str,
 
         groupAccount = \
             hasGroupType(baseDir, messageJson['actor'], personCache)
+        if groupAccount and isGroupAccount(baseDir, nickname, domain):
+            print('Group cannot follow a group')
+            return False
 
         print('Storing follow request for approval')
         return _storeFollowRequest(baseDir,
@@ -791,6 +795,10 @@ def receiveFollowRequest(session, baseDir: str, httpPrefix: str,
                     if debug:
                         print(approveHandle + ' / ' + messageJson['actor'] +
                               ' is Group: ' + str(groupAccount))
+                    if groupAccount and \
+                       isGroupAccount(baseDir, nickname, domain):
+                        print('Group cannot follow a group')
+                        return False
                     try:
                         with open(followersFilename, 'r+') as followersFile:
                             content = followersFile.read()

inbox.py

@@ -1876,18 +1876,6 @@ def _groupHandle(baseDir: str, handle: str) -> bool:
     return actorJson['type'] == 'Group'
 
 
-def _getGroupName(baseDir: str, handle: str) -> str:
-    """Returns the preferred name of a group
-    """
-    actorFile = baseDir + '/accounts/' + handle + '.json'
-    if not os.path.isfile(actorFile):
-        return False
-    actorJson = loadJson(actorFile)
-    if not actorJson:
-        return 'Group'
-    return actorJson['name']
-
-
 def _sendToGroupMembers(session, baseDir: str, handle: str, port: int,
                         postJsonObject: {},
                         httpPrefix: str, federationList: [],

shares.py

@@ -1584,7 +1584,12 @@ def _generateNextSharesTokenUpdate(baseDir: str,
     """Creates a file containing the next date when the shared items token
     for this instance will be updated
     """
-    tokenUpdateFilename = baseDir + '/accounts/.tokenUpdate'
+    tokenUpdateDir = baseDir + '/accounts'
+    if not os.path.isdir(baseDir):
+        os.mkdir(baseDir)
+    if not os.path.isdir(tokenUpdateDir):
+        os.mkdir(tokenUpdateDir)
+    tokenUpdateFilename = tokenUpdateDir + '/.tokenUpdate'
     nextUpdateSec = None
     if os.path.isfile(tokenUpdateFilename):
         with open(tokenUpdateFilename, 'r') as fp:

tests.py

@@ -42,6 +42,7 @@ from follow import clearFollowers
 from follow import sendFollowRequestViaServer
 from follow import sendUnfollowRequestViaServer
 from siteactive import siteIsActive
+from utils import isGroupAccount
 from utils import getActorLanguagesList
 from utils import getCategoryTypes
 from utils import getSupportedLanguages
@@ -1291,6 +1292,7 @@ def testFollowBetweenServers():
                                       aliceDomain +
                                       '/followingCalendar.txt').read()
     assert not isGroupActor(aliceDir, bobActor, alicePersonCache)
+    assert not isGroupAccount(aliceDir, 'alice', aliceDomain)
 
     print('\n\n*********************************************************')
     print('Alice sends a message to Bob')
@@ -1485,6 +1487,7 @@ def testSharedItemsFederation():
                                       aliceDomain +
                                       '/followingCalendar.txt').read()
     assert not isGroupActor(aliceDir, bobActor, alicePersonCache)
+    assert not isGroupAccount(bobDir, 'bob', bobDomain)
 
     print('\n\n*********************************************************')
     print('Bob publishes some shared items')
@@ -1914,6 +1917,8 @@ def testGroupFollow():
         print('Alice following.txt does not contain !testgroup@' +
               testgroupDomain + ':' + str(testgroupPort))
     assert isGroupActor(aliceDir, testgroupActor, alicePersonCache)
+    assert not isGroupAccount(aliceDir, 'alice', aliceDomain)
+    assert isGroupAccount(testgroupDir, 'testgroup', testgroupDomain)
     assert '!testgroup' in followingStr
     assert testgroupHandle in open(aliceFollowingFilename).read()
     assert testgroupHandle in open(aliceFollowingCalendarFilename).read()

utils.py

@@ -2787,6 +2787,17 @@ def isGroupActor(baseDir: str, actor: str, personCache: {},
     return False
 
 
+def isGroupAccount(baseDir: str, nickname: str, domain: str) -> bool:
+    """Returns true if the given account is a group
+    """
+    accountFilename = acctDir(baseDir, nickname, domain) + '.json'
+    if not os.path.isfile(accountFilename):
+        return False
+    if '"type": "Group"' in open(accountFilename).read():
+        return True
+    return False
+
+
 def getCurrencies() -> {}:
     """Returns a dictionary of currencies
     """