towerops/lib/towerops_web/plugs/update_session_activity.ex
Graham McIntire 7a3950d1ad chore: add jump_credo_checks ~> 0.4 with all 19 checks enabled
All checks set to exit_status: 0 initially to avoid blocking on
pre-existing violations. Remove exit_status overrides as each
check category is cleaned up incrementally.

Dependency added to dev/test only.
2026-06-12 13:45:59 -05:00

85 lines
2.5 KiB
Elixir

defmodule ToweropsWeb.Plugs.UpdateSessionActivity do
@moduledoc """
Updates the last_activity_at timestamp for the current browser session on each request.
This plug tracks session activity and enforces an inactivity timeout of 30 minutes.
If a session has been inactive for longer than the timeout, the user is automatically
logged out for security purposes.
The activity timestamp is used in the Sessions tab of User Settings to show when
each session was last active. The update happens in a background task to avoid
slowing down requests.
"""
import Plug.Conn
alias Towerops.Accounts
# 30 minutes of inactivity before automatic logout
@inactivity_timeout_seconds 30 * 60
@doc """
Initializes the plug with options (currently unused).
"""
def init(opts), do: opts
@doc """
Updates the last_activity_at timestamp for the current browser session.
Checks for session inactivity timeout and revokes the token if the session
has been inactive for more than 30 minutes. All database work runs in a
background task so the request is not blocked.
When a timed-out session is detected, the token is deleted so the next
request will be unauthenticated and redirected to login by the auth pipeline.
Looks up the session by the token stored in the session cookie, then
updates the timestamp in a background task.
"""
def call(conn, _opts) do
case get_session(conn, :user_token) do
nil ->
conn
token ->
live_socket_id = get_session(conn, :live_socket_id)
_ =
Task.Supervisor.start_child(Towerops.TaskSupervisor, fn ->
handle_session_activity(token, live_socket_id)
end)
conn
end
end
@doc false
def handle_session_activity(token, live_socket_id) do
case Accounts.get_browser_session_by_token_value(token) do
nil ->
:ok
session ->
if session_timed_out?(session) do
revoke_inactive_session(token, live_socket_id)
else
Accounts.touch_browser_session(session)
end
end
end
@doc false
def session_timed_out?(session) do
last_activity = session.last_activity_at || session.inserted_at
inactive_seconds = DateTime.diff(DateTime.utc_now(), last_activity, :second)
inactive_seconds > @inactivity_timeout_seconds
end
@doc false
def revoke_inactive_session(token, live_socket_id) do
Accounts.delete_user_session_token(token)
if live_socket_id do
ToweropsWeb.Endpoint.broadcast(live_socket_id, "disconnect", %{})
end
end
end