Added groups and restricted access.

Backend/Groups.py

@@ -0,0 +1,140 @@
+from __future__ import annotations
+
+import tomllib
+
+from typing import Any
+
+import tomli_w
+
+from Settings import GetDataDirectory
+
+
+AdminGroupName = "Admin"
+
+
+def GetGroupsPath():
+    return GetDataDirectory() / "Groups.toml"
+
+
+def LoadGroups() -> dict[str, list[str]]:
+    GroupsPath = GetGroupsPath()
+
+    if not GroupsPath.is_file():
+        # First run after upgrading from the old boolean-flag admin model:
+        # seed the Admin group from whoever already had IsAdmin set, so
+        # nobody silently loses admin access.
+        from Users import LoadUsers
+
+        SeededAdmins = [
+            Username for Username, Data in LoadUsers().items() if Data.get("IsAdmin", False)
+        ]
+        Groups = {AdminGroupName: SeededAdmins}
+        SaveGroups(Groups)
+        return Groups
+
+    with GroupsPath.open("rb") as GroupsFile:
+        Loaded = tomllib.load(GroupsFile)
+
+    Groups = Loaded.get("Groups", {})
+
+    if AdminGroupName not in Groups:
+        Groups[AdminGroupName] = []
+        SaveGroups(Groups)
+
+    return Groups
+
+
+def SaveGroups(Groups: dict[str, list[str]]) -> None:
+    GetDataDirectory().mkdir(parents=True, exist_ok=True)
+
+    with GetGroupsPath().open("wb") as GroupsFile:
+        tomli_w.dump({"Groups": Groups}, GroupsFile)
+
+
+def ListGroups() -> list[dict[str, Any]]:
+    Groups = LoadGroups()
+    return [{"Name": Name, "Members": Members} for Name, Members in sorted(Groups.items())]
+
+
+def CreateGroup(Name: str) -> None:
+    Name = Name.strip()
+
+    if not Name:
+        raise ValueError("Group name cannot be empty.")
+
+    Groups = LoadGroups()
+
+    if Name in Groups:
+        raise ValueError(f"Group '{Name}' already exists.")
+
+    Groups[Name] = []
+    SaveGroups(Groups)
+
+
+def DeleteGroup(Name: str) -> None:
+    if Name == AdminGroupName:
+        raise ValueError("The Admin group can't be deleted.")
+
+    Groups = LoadGroups()
+
+    if Name not in Groups:
+        raise ValueError(f"Group '{Name}' does not exist.")
+
+    del Groups[Name]
+    SaveGroups(Groups)
+
+
+def SetGroupMembers(Name: str, Members: list[str]) -> None:
+    Groups = LoadGroups()
+
+    if Name not in Groups:
+        raise ValueError(f"Group '{Name}' does not exist.")
+
+    # De-duplicate while keeping things predictable.
+    Groups[Name] = sorted(set(Members))
+    SaveGroups(Groups)
+
+
+def AddMember(GroupName: str, Username: str) -> None:
+    Groups = LoadGroups()
+
+    if GroupName not in Groups:
+        raise ValueError(f"Group '{GroupName}' does not exist.")
+
+    if Username not in Groups[GroupName]:
+        Groups[GroupName].append(Username)
+        SaveGroups(Groups)
+
+
+def RemoveMember(GroupName: str, Username: str) -> None:
+    Groups = LoadGroups()
+
+    if GroupName not in Groups:
+        raise ValueError(f"Group '{GroupName}' does not exist.")
+
+    if Username in Groups[GroupName]:
+        Groups[GroupName].remove(Username)
+        SaveGroups(Groups)
+
+
+def GetGroupsForUser(Username: str) -> list[str]:
+    Groups = LoadGroups()
+    return [Name for Name, Members in Groups.items() if Username in Members]
+
+
+def IsUserInGroup(Username: str, GroupName: str) -> bool:
+    return Username in LoadGroups().get(GroupName, [])
+
+
+def RenameUserInGroups(OldUsername: str, NewUsername: str) -> None:
+    Groups = LoadGroups()
+    Changed = False
+
+    for Members in Groups.values():
+        if OldUsername in Members:
+            Members.remove(OldUsername)
+            Members.append(NewUsername)
+            Changed = True
+
+    if Changed:
+        SaveGroups(Groups)