| 1 | use std::sync::Arc; |
| 2 | |
| 3 | use matrix_sdk::{BoxFuture, Client, SessionChange}; |
| 4 | use ruma::OwnedDeviceId; |
| 5 | use tokio::sync::{ |
| 6 | broadcast::{self, error::RecvError}, |
| 7 | mpsc, watch, |
| 8 | }; |
| 9 | |
| 10 | use super::Logouts; |
| 11 | use crate::{Error, Event, Termination, transport::EventSender}; |
| 12 | |
| 13 | #[cfg(not(target_family = "wasm"))] |
| 14 | pub(crate) type SaveRecord = dyn Fn(Client) -> BoxFuture<'static, Result<(), Error>> + Send + Sync; |
| 15 | #[cfg(target_family = "wasm")] |
| 16 | pub(crate) type SaveRecord = dyn Fn(Client) -> BoxFuture<'static, Result<(), Error>>; |
| 17 | |
| 18 | /// how the engine keeps the saved record current, handed over by `Session::build` |
| 19 | pub(crate) struct Persistence { |
| 20 | pub(crate) save: Box<SaveRecord>, |
| 21 | /// what the sdk's own save callback made of each refresh, when the store could write |
| 22 | /// there and then |
| 23 | pub(crate) inline: mpsc::UnboundedReceiver<Result<(), Error>>, |
| 24 | } |
| 25 | |
| 26 | impl Persistence { |
| 27 | async fn persist(&mut self, client: &Client) -> Result<(), Error> { |
| 28 | let mut inline = None; |
| 29 | while let Ok(result) = self.inline.try_recv() { |
| 30 | inline = Some(result); |
| 31 | } |
| 32 | if let Some(Ok(())) = inline { |
| 33 | return Ok(()); |
| 34 | } |
| 35 | // an inline save for a newer refresh can land while this one writes, so go again |
| 36 | // until what's on disk is what the client holds |
| 37 | loop { |
| 38 | let tokens = client.session_tokens(); |
| 39 | (self.save)(client.clone()).await?; |
| 40 | if client.session_tokens() == tokens { |
| 41 | return Ok(()); |
| 42 | } |
| 43 | } |
| 44 | } |
| 45 | } |
| 46 | |
| 47 | pub(super) enum Notice { |
| 48 | Event(Event), |
| 49 | Rejected(Option<OwnedDeviceId>), |
| 50 | } |
| 51 | |
| 52 | /// saves and notices are split, so a full event stream never holds a save back |
| 53 | pub(super) async fn session( |
| 54 | client: Client, |
| 55 | mut changes: broadcast::Receiver<SessionChange>, |
| 56 | mut persistence: Option<Persistence>, |
| 57 | notices: mpsc::UnboundedSender<Notice>, |
| 58 | device_id: OwnedDeviceId, |
| 59 | logouts: Arc<watch::Sender<Logouts>>, |
| 60 | ) { |
| 61 | loop { |
| 62 | let event = match changes.recv().await { |
| 63 | // a missed refresh costs one needless save, a missed rejection comes round again |
| 64 | Ok(SessionChange::TokensRefreshed) | Err(RecvError::Lagged(_)) => { |
| 65 | match persistence.as_mut() { |
| 66 | None => Event::SessionTokensChanged, |
| 67 | Some(persistence) => match persistence.persist(&client).await { |
| 68 | Ok(()) => Event::SessionTokensChanged, |
| 69 | Err(error) => Event::SessionSaveFailed { |
| 70 | message: error.message, |
| 71 | }, |
| 72 | }, |
| 73 | } |
| 74 | } |
| 75 | Ok(SessionChange::UnknownToken(data)) => { |
| 76 | let soft_logout = data.soft_logout.then_some(device_id); |
| 77 | let mut held = false; |
| 78 | // our own logout revokes the token, so a rejection meanwhile is its doing |
| 79 | logouts.send_if_modified(|logouts| { |
| 80 | held = logouts.in_flight > 0; |
| 81 | if held { |
| 82 | logouts.rejected = Some(soft_logout.clone()); |
| 83 | } |
| 84 | held |
| 85 | }); |
| 86 | if !held { |
| 87 | let _ = notices.send(Notice::Rejected(soft_logout)); |
| 88 | } |
| 89 | return; |
| 90 | } |
| 91 | Err(RecvError::Closed) => return, |
| 92 | }; |
| 93 | if notices.send(Notice::Event(event)).is_err() { |
| 94 | return; |
| 95 | } |
| 96 | } |
| 97 | } |
| 98 | |
| 99 | pub(super) async fn session_notices( |
| 100 | mut notices: mpsc::UnboundedReceiver<Notice>, |
| 101 | events: EventSender, |
| 102 | stop: mpsc::UnboundedSender<Termination>, |
| 103 | ) { |
| 104 | while let Some(notice) = notices.recv().await { |
| 105 | match notice { |
| 106 | Notice::Event(event) => { |
| 107 | if events.send(event).await.is_err() { |
| 108 | return; |
| 109 | } |
| 110 | } |
| 111 | Notice::Rejected(soft_logout) => { |
| 112 | return reject_session(&events, &stop, soft_logout).await; |
| 113 | } |
| 114 | } |
| 115 | } |
| 116 | } |
| 117 | |
| 118 | pub(super) async fn reject_session( |
| 119 | events: &EventSender, |
| 120 | stop: &mpsc::UnboundedSender<Termination>, |
| 121 | soft_logout: Option<OwnedDeviceId>, |
| 122 | ) { |
| 123 | let _ = events |
| 124 | .send(Event::SessionAccessRejected { |
| 125 | soft_logout: soft_logout.clone(), |
| 126 | }) |
| 127 | .await; |
| 128 | let _ = stop.send(match soft_logout { |
| 129 | Some(device_id) => Termination::SoftLoggedOut { device_id }, |
| 130 | None => Termination::AccessRevoked, |
| 131 | }); |
| 132 | } |