refactor(python-bridge): type execution errors

litellm-rust/Cargo.lock

@@ -1475,6 +1475,7 @@ dependencies = [
  "pyo3-async-runtimes",
  "serde",
  "serde_json",
+ "thiserror 2.0.19",
  "tokio",
  "tokio-tungstenite",
  "tracing",

litellm-rust/crates/python-bridge/Cargo.toml

@@ -30,6 +30,7 @@ pyo3.workspace = true
 pyo3-async-runtimes.workspace = true
 serde.workspace = true
 serde_json.workspace = true
+thiserror.workspace = true
 tokio.workspace = true
 
 [dev-dependencies]

litellm-rust/crates/python-bridge/src/errors.rs

@@ -16,6 +16,10 @@ pyo3::create_exception!(
     "The provider call was already issued and failed. Args are (status, message); status is 0 when there was no HTTP response."
 );
 
+fn upstream_error(status: u16, message: String) -> PyErr {
+    RustUpstreamError::new_err((status, message))
+}
+
 pub(crate) fn core_error_to_pyerr(err: Error) -> PyErr {
     match err {
         Error::Auth(message) => PyValueError::new_err(message),
@@ -46,11 +50,9 @@ pub(crate) fn chat_completions_error_to_pyerr(err: Error) -> PyErr {
         // Nothing reached the provider, so serving it on Python cannot double
         // bill and is the only way the caller gets an answer at all.
         | Error::Connect(_) => RustBridgeDeclined::new_err(err.to_string()),
-        Error::Http { status, body } => {
-            RustUpstreamError::new_err((status, format!("{status}: {body}")))
-        }
+        Error::Http { status, body } => upstream_error(status, format!("{status}: {body}")),
         Error::Network(message) | Error::InvalidResponse(message) => {
-            RustUpstreamError::new_err((0u16, message))
+            upstream_error(0, message)
         }
     }
 }
@@ -66,7 +68,7 @@ pub(crate) fn ocr_error_to_pyerr(err: Error) -> PyErr {
         Error::MissingField("document_url" | "image_url") => {
             PyValueError::new_err("Document URL is required")
         }
-        Error::Http { status, body } => RustUpstreamError::new_err((status, body)),
+        Error::Http { status, body } => upstream_error(status, body),
         other => core_error_to_pyerr(other),
     }
 }

litellm-rust/crates/python-bridge/src/execution.rs

@@ -11,6 +11,18 @@ use serde::Serialize;
 use tokio::runtime::{Handle, Runtime};
 use tokio::time::{self, MissedTickBehavior};
 
+#[derive(Debug, thiserror::Error)]
+enum ExecutionError {
+    #[error("synchronous native routes cannot run from a Tokio context; use the async route")]
+    SyncRouteInTokioContext,
+}
+
+impl From<ExecutionError> for PyErr {
+    fn from(error: ExecutionError) -> Self {
+        PyRuntimeError::new_err(error.to_string())
+    }
+}
+
 pub(crate) fn run_sync<T, F>(
     py: Python<'_>,
     future: F,
@@ -39,9 +51,7 @@ where
     F: Future<Output = Result<T, Error>> + Send + 'static,
 {
     if Handle::try_current().is_ok() {
-        return Err(PyRuntimeError::new_err(
-            "synchronous native routes cannot run from a Tokio context; use the async route",
-        ));
+        return Err(ExecutionError::SyncRouteInTokioContext.into());
     }
 
     let result = release_gil(py, move || runtime.block_on(wait_for_sync_result(future)))?;