Files
continuwuity/src/api/server/backfill.rs
nexy7574 7e4071c117 Implement room v12 (#943)
**Does not yet work!** Currently, state resolution does not correctly resolve conflicting states. Everything else appears to work as expected, so stateres will be fixed soon, then we should be clear for takeoff.

Also: a lot of things currently accept a nullable room ID that really just don't need to. This will need tidying up before merge. Some authentication checks have also been disabled temporarily but nothing important.

A lot of things are tagged with `TODO(hydra)`, those need resolving before merge. External contributors should PR to the `hydra/public` branch, *not* ` main`.

---

This PR should be squash merged.

Reviewed-on: https://forgejo.ellis.link/continuwuation/continuwuity/pulls/943
Co-authored-by: nexy7574 <git@nexy7574.co.uk>
Co-committed-by: nexy7574 <git@nexy7574.co.uk>
2025-09-17 20:46:03 +00:00

93 lines
2.0 KiB
Rust

use std::cmp;
use axum::extract::State;
use conduwuit::{
Event, PduCount, Result,
utils::{IterStream, ReadyExt, stream::TryTools},
};
use futures::{FutureExt, StreamExt, TryStreamExt};
use ruma::{MilliSecondsSinceUnixEpoch, api::federation::backfill::get_backfill};
use super::AccessCheck;
use crate::Ruma;
/// arbitrary number but synapse's is 100 and we can handle lots of these
/// anyways
const LIMIT_MAX: usize = 150;
/// no spec defined number but we can handle a lot of these
const LIMIT_DEFAULT: usize = 50;
/// # `GET /_matrix/federation/v1/backfill/<room_id>`
///
/// Retrieves events from before the sender joined the room, if the room's
/// history visibility allows.
pub(crate) async fn get_backfill_route(
State(services): State<crate::State>,
ref body: Ruma<get_backfill::v1::Request>,
) -> Result<get_backfill::v1::Response> {
AccessCheck {
services: &services,
origin: body.origin(),
room_id: &body.room_id,
event_id: None,
}
.check()
.await?;
let limit = body
.limit
.try_into()
.unwrap_or(LIMIT_DEFAULT)
.min(LIMIT_MAX);
let from = body
.v
.iter()
.stream()
.filter_map(|event_id| {
services
.rooms
.timeline
.get_pdu_count(event_id)
.map(Result::ok)
})
.ready_fold(PduCount::min(), cmp::max)
.await;
Ok(get_backfill::v1::Response {
origin_server_ts: MilliSecondsSinceUnixEpoch::now(),
origin: services.globals.server_name().to_owned(),
pdus: services
.rooms
.timeline
.pdus_rev(None, &body.room_id, Some(from.saturating_add(1)))
.try_take(limit)
.try_filter_map(|(_, pdu)| async move {
Ok(services
.rooms
.state_accessor
.server_can_see_event(body.origin(), &pdu.room_id_or_hash(), &pdu.event_id)
.await
.then_some(pdu))
})
.try_filter_map(|pdu| async move {
Ok(services
.rooms
.timeline
.get_pdu_json(&pdu.event_id)
.await
.ok())
})
.and_then(|pdu| {
services
.sending
.convert_to_outgoing_federation_event(pdu)
.map(Ok)
})
.try_collect()
.await?,
})
}