use std::time::Duration;
use super::*;
pub(super) struct Session {
execution: crate::execution::Execution,
pub(super) generation: u64,
disconnected: bool,
deadline: Option<tokio::time::Instant>,
pub(super) reason: &'static str,
}
impl Session {
pub(super) fn new(execution: crate::execution::Execution) -> Self {
Self { execution, generation: 1, disconnected: false, deadline: None, reason: "producer abandoned" }
}
pub(super) fn token(timeout: Duration, execution: crate::execution::Execution) -> Self {
Self { deadline: Some(execution.now() + timeout), ..Self::new(execution) }
}
pub(super) fn recovered(generation: u64, timeout: Duration, execution: crate::execution::Execution) -> Self {
Self { generation, disconnected: true, deadline: Some(execution.now() + timeout), ..Self::new(execution) }
}
pub(super) fn resumed(&mut self, generation: u64, timeout: Duration, disconnected: bool) {
self.generation = generation;
self.disconnected = disconnected;
self.deadline = Some(self.execution.now() + timeout);
}
pub(super) fn connect(&mut self) {
self.disconnected = false;
self.deadline = None;
}
pub(super) fn renew(&mut self, timeout: Duration) {
if !self.disconnected && self.deadline.is_some() {
self.deadline = Some(self.execution.now() + timeout);
}
}
pub(super) fn disconnect(&mut self, file: &StagedFile, offset: u64, timeout: Duration) {
if !self.disconnected {
self.disconnected = true;
self.deadline = Some(self.execution.now() + timeout);
tracing::warn!(file = %file.id, generation = self.generation, offset, reason = "producer disconnected", "file production retained for resume");
}
}
}
impl<C> StorageManager<C> {
pub async fn produce_file(&self, metadata: FileMetadata) -> Result<StorageFile> {
if !self.inner.primary.supports_file_sessions() {
return Err(Error::InvalidInput { field: "file session", reason: "backend does not support resumable file sessions" });
}
self.create(metadata, true).await
}
pub async fn resume_file(&self, token: &FileSession) -> Result<StorageFile> {
if let Err(error) = self.inner.primary.history().check(&token.history) {
tracing::error!(file = %token.id, generation = token.generation, reason = "history mismatch", %error, "file resume rejected");
return Err(error.into());
}
let next = token.generation.checked_add(1).ok_or_else(size_error)?;
let mut claimed = false;
let mut changed = self.inner.changed.subscribe();
loop {
let mut queued = false;
let resumed = {
let mut state = self.inner.state.lock().unwrap();
match admission(&state) {
Err(Error::Persistence { .. })
if claimed && state.files.values().any(|file| file.staging.id == token.id && file.retrying) => {}
result => result?,
}
state.expire_files();
let Some((id, file)) = state.files.iter_mut().find(|(_, file)| file.staging.id == token.id) else {
tracing::error!(file = %token.id, generation = token.generation, reason = "session unavailable or expired", "file resume rejected");
return Err(Error::InvalidInput { field: "file resume", reason: "session unavailable or expired" });
};
let session = file
.session
.as_mut()
.ok_or(Error::InvalidInput { field: "file resume", reason: "private staging is not resumable" })?;
if claimed && session.generation == next && !file.abandoned {
session.connect();
let mut token = token.clone();
token.generation = next;
Some(StorageFile { manager: self.erased(), id: *id, progress: file.progress.clone(), session: Some(token) })
} else {
if session.generation != token.generation || file.abandoned {
tracing::error!(file = %token.id, generation = token.generation, offset = file.length, reason = "expired or fenced producer", "file resume rejected");
return Err(Error::InvalidInput { field: "file resume", reason: "expired or fenced producer" });
}
if matches!(file.command, Some(Command::Finish { .. } | Command::Abort)) {
return Err(Error::InvalidInput { field: "file resume", reason: "production is ending" });
}
if !claimed && matches!(file.command, Some(Command::Resume { .. })) {
return Err(Error::InvalidInput { field: "file resume", reason: "another resume owns the transition" });
}
if file.command.is_none() && !file.in_flight {
file.command = Some(Command::Resume { expected: token.generation, next });
file.progress.lock().unwrap().generation = next;
claimed = true;
queued = true;
}
None
}
};
if queued {
self.inner.notify();
}
if let Some(file) = resumed {
return Ok(file);
}
changed.changed().await.map_err(|_| closed())?;
}
}
}
impl StorageFile {
pub fn session(&self) -> Option<&FileSession> {
self.session.as_ref()
}
pub(super) fn check_generation(&self) -> Result<()> {
if let Some(token) = &self.session
&& token.generation != self.progress.lock().unwrap().generation
{
tracing::error!(file = %token.id, generation = token.generation, reason = "producer fenced", "file operation rejected");
return Err(Error::InvalidInput { field: "file session", reason: "producer fenced" });
}
Ok(())
}
}
impl FileState {
pub(super) fn check_session(&self, token: Option<&FileSession>) -> Result<()> {
match (&self.session, token) {
(None, None) => Ok(()),
(Some(session), Some(token))
if session.generation == token.generation
&& !session.disconnected
&& session.deadline.is_none_or(|deadline| deadline > session.execution.now())
&& !self.abandoned =>
{
Ok(())
}
_ => {
tracing::error!(file = %self.staging.id, offset = self.length, reason = "producer disconnected, expired or fenced", "file operation rejected");
Err(Error::InvalidInput { field: "file session", reason: "producer disconnected, expired or fenced" })
}
}
}
}
impl State {
pub(crate) fn expire_files(&mut self) {
if self.status.closing {
return;
}
let now = self.execution.now();
for file in self.files.values_mut() {
let Some(session) = &mut file.session else {
continue;
};
if session.deadline.is_some_and(|deadline| deadline <= now)
&& !file.in_flight
&& !file.abandoned
&& !matches!(file.command, Some(Command::Finish { .. }))
{
file.abandoned = true;
session.reason =
if session.disconnected { "disconnected producer resume timeout" } else { "token producer inactivity timeout" };
file.progress.lock().unwrap().closed = true;
tracing::error!(file = %file.staging.id, generation = session.generation, offset = file.length, reason = session.reason, "file production abandoned; partial bytes retained");
}
}
}
pub(crate) fn file_deadline(&self) -> Option<tokio::time::Instant> {
if self.status.closing {
return None;
}
self.files
.values()
.filter(|file| !file.abandoned && !file.in_flight && !matches!(file.command, Some(Command::Finish { .. })))
.filter_map(|file| file.session.as_ref().and_then(|session| session.deadline))
.min()
}
}