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Diffstat (limited to 'gn_auth/auth/authorisation/groups/models.py')
| -rw-r--r-- | gn_auth/auth/authorisation/groups/models.py | 400 |
1 files changed, 400 insertions, 0 deletions
diff --git a/gn_auth/auth/authorisation/groups/models.py b/gn_auth/auth/authorisation/groups/models.py new file mode 100644 index 0000000..5a3ae50 --- /dev/null +++ b/gn_auth/auth/authorisation/groups/models.py @@ -0,0 +1,400 @@ +"""Handle the management of resource/user groups.""" +import json +from uuid import UUID, uuid4 +from functools import reduce +from typing import Any, Sequence, Iterable, Optional, NamedTuple + +from flask import g +from pymonad.maybe import Just, Maybe, Nothing + +from gn3.auth import db +from gn3.auth.dictify import dictify +from gn3.auth.authentication.users import User, user_by_id + +from ..checks import authorised_p +from ..privileges import Privilege +from ..errors import NotFoundError, AuthorisationError, InconsistencyError +from ..roles.models import ( + Role, create_role, check_user_editable, revoke_user_role_by_name, + assign_user_role_by_name) + +class Group(NamedTuple): + """Class representing a group.""" + group_id: UUID + group_name: str + group_metadata: dict[str, Any] + + def dictify(self): + """Return a dict representation of `Group` objects.""" + return { + "group_id": self.group_id, "group_name": self.group_name, + "group_metadata": self.group_metadata + } + +DUMMY_GROUP = Group( + group_id=UUID("77cee65b-fe29-4383-ae41-3cb3b480cc70"), + group_name="GN3_DUMMY_GROUP", + group_metadata={ + "group-description": "This is a dummy group to use as a placeholder" + }) + +class GroupRole(NamedTuple): + """Class representing a role tied/belonging to a group.""" + group_role_id: UUID + group: Group + role: Role + + def dictify(self) -> dict[str, Any]: + """Return a dict representation of `GroupRole` objects.""" + return { + "group_role_id": self.group_role_id, "group": dictify(self.group), + "role": dictify(self.role) + } + +class GroupCreationError(AuthorisationError): + """Raised whenever a group creation fails""" + +class MembershipError(AuthorisationError): + """Raised when there is an error with a user's membership to a group.""" + + def __init__(self, user: User, groups: Sequence[Group]): + """Initialise the `MembershipError` exception object.""" + groups_str = ", ".join(group.group_name for group in groups) + error_description = ( + f"User '{user.name} ({user.email})' is a member of {len(groups)} " + f"groups ({groups_str})") + super().__init__(f"{type(self).__name__}: {error_description}.") + +def user_membership(conn: db.DbConnection, user: User) -> Sequence[Group]: + """Returns all the groups that a member belongs to""" + query = ( + "SELECT groups.group_id, group_name, groups.group_metadata " + "FROM group_users INNER JOIN groups " + "ON group_users.group_id=groups.group_id " + "WHERE group_users.user_id=?") + with db.cursor(conn) as cursor: + cursor.execute(query, (str(user.user_id),)) + groups = tuple(Group(row[0], row[1], json.loads(row[2])) + for row in cursor.fetchall()) + + return groups + +@authorised_p( + privileges = ("system:group:create-group",), + error_description = ( + "You do not have the appropriate privileges to enable you to " + "create a new group."), + oauth2_scope = "profile group") +def create_group( + conn: db.DbConnection, group_name: str, group_leader: User, + group_description: Optional[str] = None) -> Group: + """Create a new group.""" + user_groups = user_membership(conn, group_leader) + if len(user_groups) > 0: + raise MembershipError(group_leader, user_groups) + + with db.cursor(conn) as cursor: + new_group = save_group( + cursor, group_name,( + {"group_description": group_description} + if group_description else {})) + add_user_to_group(cursor, new_group, group_leader) + revoke_user_role_by_name(cursor, group_leader, "group-creator") + assign_user_role_by_name(cursor, group_leader, "group-leader") + return new_group + +@authorised_p(("group:role:create-role",), + error_description="Could not create the group role") +def create_group_role( + conn: db.DbConnection, group: Group, role_name: str, + privileges: Iterable[Privilege]) -> GroupRole: + """Create a role attached to a group.""" + with db.cursor(conn) as cursor: + group_role_id = uuid4() + role = create_role(cursor, role_name, privileges) + cursor.execute( + ("INSERT INTO group_roles(group_role_id, group_id, role_id) " + "VALUES(?, ?, ?)"), + (str(group_role_id), str(group.group_id), str(role.role_id))) + + return GroupRole(group_role_id, group, role) + +def authenticated_user_group(conn) -> Maybe: + """ + Returns the currently authenticated user's group. + + Look into returning a Maybe object. + """ + user = g.user + with db.cursor(conn) as cursor: + cursor.execute( + ("SELECT groups.* FROM group_users " + "INNER JOIN groups ON group_users.group_id=groups.group_id " + "WHERE group_users.user_id = ?"), + (str(user.user_id),)) + groups = tuple(Group(UUID(row[0]), row[1], json.loads(row[2] or "{}")) + for row in cursor.fetchall()) + + if len(groups) > 1: + raise MembershipError(user, groups) + + if len(groups) == 1: + return Just(groups[0]) + + return Nothing + +def user_group(conn: db.DbConnection, user: User) -> Maybe[Group]: + """Returns the given user's group""" + with db.cursor(conn) as cursor: + cursor.execute( + ("SELECT groups.group_id, groups.group_name, groups.group_metadata " + "FROM group_users " + "INNER JOIN groups ON group_users.group_id=groups.group_id " + "WHERE group_users.user_id = ?"), + (str(user.user_id),)) + groups = tuple( + Group(UUID(row[0]), row[1], json.loads(row[2] or "{}")) + for row in cursor.fetchall()) + + if len(groups) > 1: + raise MembershipError(user, groups) + + if len(groups) == 1: + return Just(groups[0]) + + return Nothing + +def is_group_leader(conn: db.DbConnection, user: User, group: Group) -> bool: + """Check whether the given `user` is the leader of `group`.""" + + ugroup = user_group(conn, user).maybe( + False, lambda val: val) # type: ignore[arg-type, misc] + if not group: + # User cannot be a group leader if not a member of ANY group + return False + + if not ugroup == group: + # User cannot be a group leader if not a member of THIS group + return False + + with db.cursor(conn) as cursor: + cursor.execute( + ("SELECT roles.role_name FROM user_roles LEFT JOIN roles " + "ON user_roles.role_id = roles.role_id WHERE user_id = ?"), + (str(user.user_id),)) + role_names = tuple(row[0] for row in cursor.fetchall()) + + return "group-leader" in role_names + +def all_groups(conn: db.DbConnection) -> Maybe[Sequence[Group]]: + """Retrieve all existing groups""" + with db.cursor(conn) as cursor: + cursor.execute("SELECT * FROM groups") + res = cursor.fetchall() + if res: + return Just(tuple( + Group(row["group_id"], row["group_name"], + json.loads(row["group_metadata"])) for row in res)) + + return Nothing + +def save_group( + cursor: db.DbCursor, group_name: str, + group_metadata: dict[str, Any]) -> Group: + """Save a group to db""" + the_group = Group(uuid4(), group_name, group_metadata) + cursor.execute( + ("INSERT INTO groups " + "VALUES(:group_id, :group_name, :group_metadata) " + "ON CONFLICT (group_id) DO UPDATE SET " + "group_name=:group_name, group_metadata=:group_metadata"), + {"group_id": str(the_group.group_id), "group_name": the_group.group_name, + "group_metadata": json.dumps(the_group.group_metadata)}) + return the_group + +def add_user_to_group(cursor: db.DbCursor, the_group: Group, user: User): + """Add `user` to `the_group` as a member.""" + cursor.execute( + ("INSERT INTO group_users VALUES (:group_id, :user_id) " + "ON CONFLICT (group_id, user_id) DO NOTHING"), + {"group_id": str(the_group.group_id), "user_id": str(user.user_id)}) + +@authorised_p( + privileges = ("system:group:view-group",), + error_description = ( + "You do not have the appropriate privileges to access the list of users" + " in the group.")) +def group_users(conn: db.DbConnection, group_id: UUID) -> Iterable[User]: + """Retrieve all users that are members of group with id `group_id`.""" + with db.cursor(conn) as cursor: + cursor.execute( + "SELECT u.* FROM group_users AS gu INNER JOIN users AS u " + "ON gu.user_id = u.user_id WHERE gu.group_id=:group_id", + {"group_id": str(group_id)}) + results = cursor.fetchall() + + return (User(UUID(row["user_id"]), row["email"], row["name"]) + for row in results) + +@authorised_p( + privileges = ("system:group:view-group",), + error_description = ( + "You do not have the appropriate privileges to access the group.")) +def group_by_id(conn: db.DbConnection, group_id: UUID) -> Group: + """Retrieve a group by its ID""" + with db.cursor(conn) as cursor: + cursor.execute("SELECT * FROM groups WHERE group_id=:group_id", + {"group_id": str(group_id)}) + row = cursor.fetchone() + if row: + return Group( + UUID(row["group_id"]), + row["group_name"], + json.loads(row["group_metadata"])) + + raise NotFoundError(f"Could not find group with ID '{group_id}'.") + +@authorised_p(("system:group:view-group", "system:group:edit-group"), + error_description=("You do not have the appropriate authorisation" + " to act upon the join requests."), + oauth2_scope="profile group") +def join_requests(conn: db.DbConnection, user: User): + """List all the join requests for the user's group.""" + with db.cursor(conn) as cursor: + group = user_group(conn, user).maybe(DUMMY_GROUP, lambda grp: grp)# type: ignore[misc] + if group != DUMMY_GROUP and is_group_leader(conn, user, group): + cursor.execute( + "SELECT gjr.*, u.email, u.name FROM group_join_requests AS gjr " + "INNER JOIN users AS u ON gjr.requester_id=u.user_id " + "WHERE gjr.group_id=? AND gjr.status='PENDING'", + (str(group.group_id),)) + return tuple(dict(row)for row in cursor.fetchall()) + + raise AuthorisationError( + "You do not have the appropriate authorisation to access the " + "group's join requests.") + +@authorised_p(("system:group:view-group", "system:group:edit-group"), + error_description=("You do not have the appropriate authorisation" + " to act upon the join requests."), + oauth2_scope="profile group") +def accept_reject_join_request( + conn: db.DbConnection, request_id: UUID, user: User, status: str) -> dict: + """Accept/Reject a join request.""" + assert status in ("ACCEPTED", "REJECTED"), f"Invalid status '{status}'." + with db.cursor(conn) as cursor: + group = user_group(conn, user).maybe(DUMMY_GROUP, lambda grp: grp) # type: ignore[misc] + cursor.execute("SELECT * FROM group_join_requests WHERE request_id=?", + (str(request_id),)) + row = cursor.fetchone() + if row: + if group.group_id == UUID(row["group_id"]): + try: + the_user = user_by_id(conn, UUID(row["requester_id"])) + if status == "ACCEPTED": + add_user_to_group(cursor, group, the_user) + revoke_user_role_by_name(cursor, the_user, "group-creator") + cursor.execute( + "UPDATE group_join_requests SET status=? " + "WHERE request_id=?", + (status, str(request_id))) + return {"request_id": request_id, "status": status} + except NotFoundError as nfe: + raise InconsistencyError( + "Could not find user associated with join request." + ) from nfe + raise AuthorisationError( + "You cannot act on other groups join requests") + raise NotFoundError(f"Could not find request with ID '{request_id}'") + +def __organise_privileges__(acc, row): + role_id = UUID(row["role_id"]) + role = acc.get(role_id, False) + if role: + return { + **acc, + role_id: Role( + role.role_id, role.role_name, + bool(int(row["user_editable"])), + role.privileges + ( + Privilege(row["privilege_id"], + row["privilege_description"]),)) + } + return { + **acc, + role_id: Role( + UUID(row["role_id"]), row["role_name"], + bool(int(row["user_editable"])), + (Privilege(row["privilege_id"], row["privilege_description"]),)) + } + +# @authorised_p(("group:role:view",), +# "Insufficient privileges to view role", +# oauth2_scope="profile group role") +def group_role_by_id( + conn: db.DbConnection, group: Group, group_role_id: UUID) -> GroupRole: + """Retrieve GroupRole from id by its `group_role_id`.""" + ## TODO: do privileges check before running actual query + ## the check commented out above doesn't work correctly + with db.cursor(conn) as cursor: + cursor.execute( + "SELECT gr.group_role_id, r.*, p.* " + "FROM group_roles AS gr " + "INNER JOIN roles AS r ON gr.role_id=r.role_id " + "INNER JOIN role_privileges AS rp ON rp.role_id=r.role_id " + "INNER JOIN privileges AS p ON p.privilege_id=rp.privilege_id " + "WHERE gr.group_role_id=? AND gr.group_id=?", + (str(group_role_id), str(group.group_id))) + rows = cursor.fetchall() + if rows: + roles: tuple[Role,...] = tuple(reduce( + __organise_privileges__, rows, {}).values()) + assert len(roles) == 1 + return GroupRole(group_role_id, group, roles[0]) + raise NotFoundError( + f"Group role with ID '{group_role_id}' does not exist.") + +@authorised_p(("group:role:edit-role",), + "You do not have the privilege to edit a role.", + oauth2_scope="profile group role") +def add_privilege_to_group_role(conn: db.DbConnection, group_role: GroupRole, + privilege: Privilege) -> GroupRole: + """Add `privilege` to `group_role`.""" + ## TODO: do privileges check. + check_user_editable(group_role.role) + with db.cursor(conn) as cursor: + cursor.execute( + "INSERT INTO role_privileges(role_id,privilege_id) " + "VALUES (?, ?) ON CONFLICT (role_id, privilege_id) " + "DO NOTHING", + (str(group_role.role.role_id), str(privilege.privilege_id))) + return GroupRole( + group_role.group_role_id, + group_role.group, + Role(group_role.role.role_id, + group_role.role.role_name, + group_role.role.user_editable, + group_role.role.privileges + (privilege,))) + +@authorised_p(("group:role:edit-role",), + "You do not have the privilege to edit a role.", + oauth2_scope="profile group role") +def delete_privilege_from_group_role( + conn: db.DbConnection, group_role: GroupRole, + privilege: Privilege) -> GroupRole: + """Delete `privilege` to `group_role`.""" + ## TODO: do privileges check. + check_user_editable(group_role.role) + with db.cursor(conn) as cursor: + cursor.execute( + "DELETE FROM role_privileges WHERE " + "role_id=? AND privilege_id=?", + (str(group_role.role.role_id), str(privilege.privilege_id))) + return GroupRole( + group_role.group_role_id, + group_role.group, + Role(group_role.role.role_id, + group_role.role.role_name, + group_role.role.user_editable, + tuple(priv for priv in group_role.role.privileges + if priv != privilege))) |