From 85e70ea3746c7981bb379f1344dc2eed4286f7b8 Mon Sep 17 00:00:00 2001 From: Yujong Lee Date: Wed, 16 Sep 2026 20:49:31 -0700 Subject: [PATCH] fix(ocr): await blocking preparation on cancellation --- litellm-rust/crates/core/src/ocr/lifecycle.rs | 56 +++++++++++-- litellm-rust/crates/core/tests/ocr.rs | 80 +++++++++++++++++++ 2 files changed, 129 insertions(+), 7 deletions(-) diff --git a/litellm-rust/crates/core/src/ocr/lifecycle.rs b/litellm-rust/crates/core/src/ocr/lifecycle.rs index b8b81a6b672..f2e5479b361 100644 --- a/litellm-rust/crates/core/src/ocr/lifecycle.rs +++ b/litellm-rust/crates/core/src/ocr/lifecycle.rs @@ -1,10 +1,11 @@ use std::future::Future; use std::pin::Pin; use std::sync::Arc; +use std::sync::atomic::{AtomicBool, Ordering}; use litellm_auth::Error as AuthError; use litellm_auth::{ResolvedCredential, TokenFuture, TokenProvider, TokenProviderHandle}; -use tokio::sync::{mpsc, oneshot}; +use tokio::sync::{Notify, mpsc, oneshot}; use super::handler::perform_ocr_request; use super::hooks::{ @@ -321,6 +322,7 @@ struct OcrExecution { operations_rx: mpsc::UnboundedReceiver, pending_result: Option>, execution: Option>>, + blocking_preparation: Arc, completed: bool, azure_ad_token_provider: bool, terminal: Arc>>, @@ -336,6 +338,7 @@ impl OcrExecution { operations_rx, pending_result: None, execution: None, + blocking_preparation: Arc::new(BlockingPreparation::default()), completed: false, azure_ad_token_provider: false, terminal: Arc::default(), @@ -406,8 +409,9 @@ impl OcrExecution { terminal: self.terminal.clone(), }); request.hooks = hooks.clone(); + let blocking_preparation = self.blocking_preparation.clone(); self.execution = Some(tokio::spawn(async move { - let request = prepare_request_document(request, &hooks).await?; + let request = prepare_request_document(request, &hooks, blocking_preparation).await?; perform_ocr_request(&client, request).await })); } @@ -424,13 +428,47 @@ impl OcrExecution { if let Some(execution) = self.execution.as_mut() { let _ = execution.await; } + self.blocking_preparation.wait().await; self.execution = None; } } +#[derive(Default)] +struct BlockingPreparation { + running: AtomicBool, + finished: Notify, +} + +impl BlockingPreparation { + fn start(self: &Arc) -> BlockingPreparationGuard { + self.running.store(true, Ordering::Release); + BlockingPreparationGuard(self.clone()) + } + + async fn wait(&self) { + loop { + let finished = self.finished.notified(); + if !self.running.load(Ordering::Acquire) { + return; + } + finished.await; + } + } +} + +struct BlockingPreparationGuard(Arc); + +impl Drop for BlockingPreparationGuard { + fn drop(&mut self) { + self.0.running.store(false, Ordering::Release); + self.0.finished.notify_waiters(); + } +} + async fn prepare_request_document( request: LiteLLMOcrRequest, hooks: &ProtocolHooks, + blocking_preparation: Arc, ) -> Result { let request = match &request.document { OcrDocumentInput::HostReader { mime_type } => { @@ -454,11 +492,15 @@ async fn prepare_request_document( if let OcrDocumentInput::Document(_) = &request.document { return request.map_document(super::document::prepare_document); } - tokio::task::spawn_blocking(move || request.map_document(super::document::prepare_document)) - .await - .map_err(|error| { - Error::InvalidRequest(format!("OCR document preparation task failed: {error}")) - })? + let guard = blocking_preparation.start(); + tokio::task::spawn_blocking(move || { + let _guard = guard; + request.map_document(super::document::prepare_document) + }) + .await + .map_err(|error| { + Error::InvalidRequest(format!("OCR document preparation task failed: {error}")) + })? } impl Drop for OcrExecution { diff --git a/litellm-rust/crates/core/tests/ocr.rs b/litellm-rust/crates/core/tests/ocr.rs index 78dfd5a2c9f..480774d1ad1 100644 --- a/litellm-rust/crates/core/tests/ocr.rs +++ b/litellm-rust/crates/core/tests/ocr.rs @@ -744,6 +744,86 @@ async fn cancellation_at_provider_hook_prevents_execution_and_further_resumption ); } +#[cfg(unix)] +#[tokio::test] +async fn cancellation_acknowledges_blocking_preparation_completion() { + use std::future::Future; + use std::io::Write; + use std::task::Poll; + + use crate::call_lifecycle::host::HostFailure; + + let path = std::env::temp_dir().join(format!("litellm-ocr-{}.fifo", rand::random::())); + assert!( + std::process::Command::new("mkfifo") + .arg(&path) + .status() + .unwrap() + .success() + ); + let request = wire_request("mistral/model", "http://127.0.0.1:1", json!({})).with_document( + super::OcrDocumentInput::Path { + path: path.clone(), + mime_type: Some("application/pdf".into()), + }, + ); + let NativeOutcome::Completed(mut call) = + OcrCall::admit(super::test_support::ocr_client(), OcrAdmission::all()) + else { + panic!("supported call declined") + }; + let mut request = Some(request); + let mut result = None; + loop { + match call.resume(result.take()).await.unwrap() { + OcrCallStep::Host(OcrHostOperation::ProjectRequest) => break, + OcrCallStep::Host(operation) => result = Some(NoopOcrHost.invoke(operation).await), + OcrCallStep::Complete(_) => panic!("provider executed before request projection"), + } + } + let mut preparation = Box::pin(call.resume(Some(OcrHostResult::Request(Ok(( + Box::new(request.take().unwrap()), + false, + )))))); + std::future::poll_fn(|cx| { + assert!(preparation.as_mut().poll(cx).is_pending()); + Poll::Ready(()) + }) + .await; + drop(preparation); + + let (entered_tx, entered_rx) = tokio::sync::oneshot::channel(); + let (release_tx, release_rx) = std::sync::mpsc::channel(); + let writer_path = path.clone(); + let writer = tokio::task::spawn_blocking(move || { + let mut fifo = std::fs::File::options() + .write(true) + .open(writer_path) + .unwrap(); + entered_tx.send(()).unwrap(); + release_rx.recv().unwrap(); + fifo.write_all(b"document").unwrap(); + }); + tokio::time::timeout(std::time::Duration::from_secs(2), entered_rx) + .await + .unwrap() + .unwrap(); + + let selected = crate::ocr::Error::InvalidRequest("cancelled".into()); + let mut acknowledgement = Box::pin(call.interrupt(HostFailure::Cancelled(selected.clone()))); + std::future::poll_fn(|cx| { + assert!(acknowledgement.as_mut().poll(cx).is_pending()); + Poll::Ready(()) + }) + .await; + release_tx.send(()).unwrap(); + assert!( + matches!(acknowledgement.await, Err(crate::ocr::Error::InvalidRequest(message)) if message == "cancelled") + ); + writer.await.unwrap(); + std::fs::remove_file(path).unwrap(); +} + #[tokio::test] async fn missing_host_result_preserves_pending_operation() { use crate::call_lifecycle::host::HostPhase;