Always attach URL to network errors

Due to the enduring problems with #8144 and related issues, I've opted for a more systemic approach and switched all reqwest errors to not use the implicit-try-fallthrough `#[from]`, but an explicit `#[source]` with a URL attached (except for when there is only one or no URL). This guarantees that we get the URL that failed, and helps identifying the responsible code path.

Author: konstin

crates/uv-client/src/cached_client.rs

@@ -468,9 +468,9 @@ impl CachedClient {
             .execute(req)
             .instrument(info_span!("revalidation_request", url = url.as_str()))
             .await
-            .map_err(ErrorKind::from)?
+            .map_err(|err| ErrorKind::from_reqwest_middleware(url.clone(), err))?
             .error_for_status()
-            .map_err(ErrorKind::from)?;
+            .map_err(|err| ErrorKind::from_reqwest(url.clone(), err))?;
         match cached
             .cache_policy
             .after_response(new_cache_policy_builder, &response)
@@ -500,16 +500,17 @@ impl CachedClient {
         &self,
         req: Request,
     ) -> Result<(Response, Option<Box<CachePolicy>>), Error> {
-        trace!("Sending fresh {} request for {}", req.method(), req.url());
+        let url = req.url().clone();
+        trace!("Sending fresh {} request for {}", req.method(), url);
         let cache_policy_builder = CachePolicyBuilder::new(&req);
         let response = self
             .0
-            .for_host(req.url())
+            .for_host(&url)
             .execute(req)
             .await
-            .map_err(ErrorKind::from)?
+            .map_err(|err| ErrorKind::from_reqwest_middleware(url.clone(), err))?
             .error_for_status()
-            .map_err(ErrorKind::from)?;
+            .map_err(|err| ErrorKind::from_reqwest(url.clone(), err))?;
         let cache_policy = cache_policy_builder.build(&response);
         let cache_policy = if cache_policy.to_archived().is_storable() {
             Some(Box::new(cache_policy))

crates/uv-client/src/error.rs

@@ -73,7 +73,7 @@ impl Error {
 
             // The server returned a "Method Not Allowed" error, indicating it doesn't support
             // HEAD requests, so we can't check for range requests.
-            ErrorKind::WrappedReqwestError(err) => {
+            ErrorKind::WrappedReqwestError(_url, err) => {
                 if let Some(status) = err.status() {
                     // If the server doesn't support HEAD requests, we can't check for range
                     // requests.
@@ -180,8 +180,8 @@ pub enum ErrorKind {
     MetadataNotFound(WheelFilename, String),
 
     /// An error that happened while making a request or in a reqwest middleware.
-    #[error(transparent)]
-    WrappedReqwestError(#[from] WrappedReqwestError),
+    #[error("Failed to fetch {0}")]
+    WrappedReqwestError(Url, #[source] WrappedReqwestError),
 
     #[error("Received some unexpected JSON from {url}")]
     BadJson { source: serde_json::Error, url: Url },
@@ -208,7 +208,7 @@ pub enum ErrorKind {
     CacheWrite(#[source] std::io::Error),
 
     #[error(transparent)]
-    Io(#[from] std::io::Error),
+    Io(std::io::Error),
 
     #[error("Cache deserialization failed")]
     Decode(#[source] rmp_serde::decode::Error),
@@ -235,21 +235,19 @@ pub enum ErrorKind {
     Offline(String),
 }
 
-impl From<reqwest::Error> for ErrorKind {
-    fn from(error: reqwest::Error) -> Self {
-        Self::WrappedReqwestError(WrappedReqwestError::from(error))
+impl ErrorKind {
+    pub(crate) fn from_reqwest(url: Url, error: reqwest::Error) -> Self {
+        Self::WrappedReqwestError(url, WrappedReqwestError::from(error))
     }
-}
 
-impl From<reqwest_middleware::Error> for ErrorKind {
-    fn from(err: reqwest_middleware::Error) -> Self {
+    pub(crate) fn from_reqwest_middleware(url: Url, err: reqwest_middleware::Error) -> Self {
         if let reqwest_middleware::Error::Middleware(ref underlying) = err {
             if let Some(err) = underlying.downcast_ref::<OfflineError>() {
                 return Self::Offline(err.url().to_string());
             }
         }
 
-        Self::WrappedReqwestError(WrappedReqwestError(err))
+        Self::WrappedReqwestError(url, WrappedReqwestError(err))
     }
 }
 

crates/uv-client/src/flat_index.rs

@@ -160,14 +160,17 @@ impl<'a> FlatIndexClient<'a> {
             .header("Accept-Encoding", "gzip")
             .header("Accept", "text/html")
             .build()
-            .map_err(ErrorKind::from)?;
+            .map_err(|err| ErrorKind::from_reqwest(url.clone(), err))?;
         let parse_simple_response = |response: Response| {
             async {
                 // Use the response URL, rather than the request URL, as the base for relative URLs.
                 // This ensures that we handle redirects and other URL transformations correctly.
                 let url = response.url().clone();
 
-                let text = response.text().await.map_err(ErrorKind::from)?;
+                let text = response
+                    .text()
+                    .await
+                    .map_err(|err| ErrorKind::from_reqwest(url.clone(), err))?;
                 let SimpleHtml { base, files } = SimpleHtml::parse(&text, &url)
                     .map_err(|err| Error::from_html_err(err, url.clone()))?;
 

crates/uv-client/src/registry_client.rs

@@ -232,15 +232,15 @@ impl RegistryClient {
                 }
                 Err(err) => match err.into_kind() {
                     // The package could not be found in the remote index.
-                    ErrorKind::WrappedReqwestError(err) => match err.status() {
+                    ErrorKind::WrappedReqwestError(url, err) => match err.status() {
                         Some(StatusCode::NOT_FOUND) => {}
                         Some(StatusCode::UNAUTHORIZED) => {
                             capabilities.set_unauthorized(index.clone());
                         }
                         Some(StatusCode::FORBIDDEN) => {
                             capabilities.set_forbidden(index.clone());
                         }
-                        _ => return Err(ErrorKind::from(err).into()),
+                        _ => return Err(ErrorKind::WrappedReqwestError(url, err).into()),
                     },
 
                     // The package is unavailable due to a lack of connectivity.
@@ -323,7 +323,7 @@ impl RegistryClient {
             .header("Accept-Encoding", "gzip")
             .header("Accept", MediaType::accepts())
             .build()
-            .map_err(ErrorKind::from)?;
+            .map_err(|err| ErrorKind::from_reqwest(url.clone(), err))?;
         let parse_simple_response = |response: Response| {
             async {
                 // Use the response URL, rather than the request URL, as the base for relative URLs.
@@ -347,14 +347,20 @@ impl RegistryClient {
 
                 let unarchived = match media_type {
                     MediaType::Json => {
-                        let bytes = response.bytes().await.map_err(ErrorKind::from)?;
+                        let bytes = response
+                            .bytes()
+                            .await
+                            .map_err(|err| ErrorKind::from_reqwest(url.clone(), err))?;
                         let data: SimpleJson = serde_json::from_slice(bytes.as_ref())
                             .map_err(|err| Error::from_json_err(err, url.clone()))?;
 
                         SimpleMetadata::from_files(data.files, package_name, &url)
                     }
                     MediaType::Html => {
-                        let text = response.text().await.map_err(ErrorKind::from)?;
+                        let text = response
+                            .text()
+                            .await
+                            .map_err(|err| ErrorKind::from_reqwest(url.clone(), err))?;
                         SimpleMetadata::from_html(&text, package_name, &url)?
                     }
                 };
@@ -547,7 +553,10 @@ impl RegistryClient {
             };
 
             let response_callback = |response: Response| async {
-                let bytes = response.bytes().await.map_err(ErrorKind::from)?;
+                let bytes = response
+                    .bytes()
+                    .await
+                    .map_err(|err| ErrorKind::from_reqwest(url.clone(), err))?;
 
                 info_span!("parse_metadata21")
                     .in_scope(|| ResolutionMetadata::parse_metadata(bytes.as_ref()))
@@ -563,7 +572,7 @@ impl RegistryClient {
                 .uncached_client(&url)
                 .get(url.clone())
                 .build()
-                .map_err(ErrorKind::from)?;
+                .map_err(|err| ErrorKind::from_reqwest(url.clone(), err))?;
             Ok(self
                 .cached_client()
                 .get_serde(req, &cache_entry, cache_control, response_callback)
@@ -616,7 +625,7 @@ impl RegistryClient {
                     http::HeaderValue::from_static("identity"),
                 )
                 .build()
-                .map_err(ErrorKind::from)?;
+                .map_err(|err| ErrorKind::from_reqwest(url.clone(), err))?;
 
             // Copy authorization headers from the HEAD request to subsequent requests
             let mut headers = HeaderMap::default();
@@ -694,7 +703,7 @@ impl RegistryClient {
                 reqwest::header::HeaderValue::from_static("identity"),
             )
             .build()
-            .map_err(ErrorKind::from)?;
+            .map_err(|err| ErrorKind::from_reqwest(url.clone(), err))?;
 
         // Stream the file, searching for the METADATA.
         let read_metadata_stream = |response: Response| {

crates/uv-client/src/tls.rs

@@ -7,12 +7,15 @@ pub(crate) enum CertificateError {
     #[error(transparent)]
     Io(#[from] std::io::Error),
     #[error(transparent)]
-    Reqwest(#[from] reqwest::Error),
+    Reqwest(reqwest::Error),
 }
 
 /// Return the `Identity` from the provided file.
 pub(crate) fn read_identity(ssl_client_cert: &OsStr) -> Result<Identity, CertificateError> {
     let mut buf = Vec::new();
     fs_err::File::open(ssl_client_cert)?.read_to_end(&mut buf)?;
-    Ok(Identity::from_pem(&buf)?)
+    Identity::from_pem(&buf).map_err(|tls_err| {
+        debug_assert!(tls_err.is_builder(), "must be a rustls::Error internally");
+        CertificateError::Reqwest(tls_err)
+    })
 }

crates/uv-distribution/src/distribution_database.rs

@@ -87,7 +87,8 @@ impl<'a, Context: BuildContext> DistributionDatabase<'a, Context> {
             io::Error::new(
                 io::ErrorKind::TimedOut,
                 format!(
-                    "Failed to download distribution due to network timeout. Try increasing UV_HTTP_TIMEOUT (current value: {}s).", self.client.unmanaged.timeout().as_secs()
+                    "Failed to download distribution due to network timeout. Try increasing UV_HTTP_TIMEOUT (current value: {}s).",
+                    self.client.unmanaged.timeout().as_secs()
                 ),
             )
         } else {

crates/uv-publish/src/lib.rs

@@ -79,7 +79,7 @@ pub enum PublishPrepareError {
 #[derive(Error, Debug)]
 pub enum PublishSendError {
     #[error("Failed to send POST request")]
-    ReqwestMiddleware(#[from] reqwest_middleware::Error),
+    ReqwestMiddleware(#[source] reqwest_middleware::Error),
     #[error("Upload failed with status {0}")]
     StatusNoBody(StatusCode, #[source] reqwest::Error),
     #[error("Upload failed with status code {0}. Server says: {1}")]
@@ -336,7 +336,11 @@ pub async fn upload(
         }
 
         let response = result.map_err(|err| {
-            PublishError::PublishSend(file.to_path_buf(), registry.clone(), err.into())
+            PublishError::PublishSend(
+                file.to_path_buf(),
+                registry.clone(),
+                PublishSendError::ReqwestMiddleware(err),
+            )
         })?;
 
         return handle_response(registry, response)

crates/uv-publish/src/trusted_publishing.rs

@@ -17,10 +17,10 @@ pub enum TrustedPublishingError {
     Var(#[from] VarError),
     #[error(transparent)]
     Url(#[from] url::ParseError),
-    #[error(transparent)]
-    Reqwest(#[from] reqwest::Error),
-    #[error(transparent)]
-    ReqwestMiddleware(#[from] reqwest_middleware::Error),
+    #[error("Failed to fetch {0}")]
+    Reqwest(Url, #[source] reqwest::Error),
+    #[error("Failed to fetch {0}")]
+    ReqwestMiddleware(Url, #[source] reqwest_middleware::Error),
     #[error(transparent)]
     SerdeJson(#[from] serde_json::error::Error),
     #[error(
@@ -105,8 +105,17 @@ async fn get_audience(
     // (RFC 3986).
     let audience_url = Url::parse(&format!("https://{}/_/oidc/audience", registry.authority()))?;
     debug!("Querying the trusted publishing audience from {audience_url}");
-    let response = client.get(audience_url).send().await?;
-    let audience = response.error_for_status()?.json::<Audience>().await?;
+    let response = client
+        .get(audience_url.clone())
+        .send()
+        .await
+        .map_err(|err| TrustedPublishingError::ReqwestMiddleware(audience_url.clone(), err))?;
+    let audience = response
+        .error_for_status()
+        .map_err(|err| TrustedPublishingError::Reqwest(audience_url.clone(), err))?
+        .json::<Audience>()
+        .await
+        .map_err(|err| TrustedPublishingError::Reqwest(audience_url.clone(), err))?;
     trace!("The audience is `{}`", &audience.audience);
     Ok(audience.audience)
 }
@@ -123,11 +132,17 @@ async fn get_oidc_token(
     debug!("Querying the trusted publishing OIDC token from {oidc_token_url}");
     let authorization = format!("bearer {oidc_token_request_token}");
     let response = client
-        .get(oidc_token_url)
+        .get(oidc_token_url.clone())
         .header(header::AUTHORIZATION, authorization)
         .send()
-        .await?;
-    let oidc_token: OidcToken = response.error_for_status()?.json().await?;
+        .await
+        .map_err(|err| TrustedPublishingError::ReqwestMiddleware(oidc_token_url.clone(), err))?;
+    let oidc_token: OidcToken = response
+        .error_for_status()
+        .map_err(|err| TrustedPublishingError::Reqwest(oidc_token_url.clone(), err))?
+        .json()
+        .await
+        .map_err(|err| TrustedPublishingError::Reqwest(oidc_token_url.clone(), err))?;
     Ok(oidc_token.value)
 }
 
@@ -145,14 +160,18 @@ async fn get_publish_token(
         token: oidc_token.to_string(),
     };
     let response = client
-        .post(mint_token_url)
+        .post(mint_token_url.clone())
         .body(serde_json::to_vec(&mint_token_payload)?)
         .send()
-        .await?;
+        .await
+        .map_err(|err| TrustedPublishingError::ReqwestMiddleware(mint_token_url.clone(), err))?;
 
     // reqwest's implementation of `.json()` also goes through `.bytes()`
     let status = response.status();
-    let body = response.bytes().await?;
+    let body = response
+        .bytes()
+        .await
+        .map_err(|err| TrustedPublishingError::Reqwest(mint_token_url.clone(), err))?;
 
     if status.is_success() {
         let publish_token: PublishToken = serde_json::from_slice(&body)?;

crates/uv-python/src/downloads.rs

@@ -39,10 +39,10 @@ pub enum Error {
     InvalidPythonVersion(String),
     #[error("Invalid request key (too many parts): {0}")]
     TooManyParts(String),
-    #[error(transparent)]
-    NetworkError(#[from] WrappedReqwestError),
-    #[error(transparent)]
-    NetworkMiddlewareError(#[from] anyhow::Error),
+    #[error("Failed to download {0}")]
+    NetworkError(Url, #[source] WrappedReqwestError),
+    #[error("Failed to download {0}")]
+    NetworkMiddlewareError(Url, #[source] anyhow::Error),
     #[error("Failed to extract archive: {0}")]
     ExtractError(String, #[source] uv_extract::Error),
     #[error("Failed to hash installation")]
@@ -612,18 +612,18 @@ impl ManagedPythonDownload {
     }
 }
 
-impl From<reqwest::Error> for Error {
-    fn from(error: reqwest::Error) -> Self {
-        Self::NetworkError(WrappedReqwestError::from(error))
+impl Error {
+    pub(crate) fn from_reqwest(url: Url, err: reqwest::Error) -> Self {
+        Self::NetworkError(url, WrappedReqwestError::from(err))
     }
-}
 
-impl From<reqwest_middleware::Error> for Error {
-    fn from(error: reqwest_middleware::Error) -> Self {
-        match error {
-            reqwest_middleware::Error::Middleware(error) => Self::NetworkMiddlewareError(error),
+    pub(crate) fn from_reqwest_middleware(url: Url, err: reqwest_middleware::Error) -> Self {
+        match err {
+            reqwest_middleware::Error::Middleware(error) => {
+                Self::NetworkMiddlewareError(url, error)
+            }
             reqwest_middleware::Error::Reqwest(error) => {
-                Self::NetworkError(WrappedReqwestError::from(error))
+                Self::NetworkError(url, WrappedReqwestError::from(error))
             }
         }
     }
@@ -694,10 +694,17 @@ async fn read_url(
 
         Ok((Either::Left(reader), Some(size)))
     } else {
-        let response = client.for_host(url).get(url.clone()).send().await?;
+        let response = client
+            .for_host(url)
+            .get(url.clone())
+            .send()
+            .await
+            .map_err(|err| Error::from_reqwest_middleware(url.clone(), err))?;
 
         // Ensure the request was successful.
-        response.error_for_status_ref()?;
+        response
+            .error_for_status_ref()
+            .map_err(|err| Error::from_reqwest(url.clone(), err))?;
 
         let size = response.content_length();
         let stream = response