Incorporate feedback

aws/rust-runtime/aws-config/src/imds/credentials.rs

@@ -13,11 +13,29 @@ use crate::imds::client::{ImdsError, LazyClient};
 use crate::json_credentials::{parse_json_credentials, JsonCredentials, RefreshableCredentials};
 use crate::provider_config::ProviderConfig;
 use aws_smithy_client::SdkError;
-use aws_smithy_types::error::display::DisplayErrorContext;
 use aws_types::credentials::{future, CredentialsError, ProvideCredentials};
 use aws_types::os_shim_internal::Env;
 use aws_types::{credentials, Credentials};
 use std::borrow::Cow;
+use std::error::Error as StdError;
+use std::fmt;
+
+#[derive(Debug)]
+struct ImdsCommunicationError {
+ source: Box<dyn StdError + Send + Sync + 'static>,
+}
+
+impl fmt::Display for ImdsCommunicationError {
+ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+ write!(f, "could not communicate with IMDS")
+ }
+}
+
+impl StdError for ImdsCommunicationError {
+ fn source(&self) -> Option<&(dyn StdError + 'static)> {
+ Some(self.source.as_ref())
+ }
+}
 
 /// IMDSv2 Credentials Provider
 ///
@@ -138,11 +156,10 @@ impl ImdsCredentialsProvider {
  );
  Err(CredentialsError::not_loaded("received 404 from IMDS"))
  }
- Err(ImdsError::FailedToLoadToken(ref err @ SdkError::DispatchFailure(_))) => {
- Err(CredentialsError::not_loaded(format!(
- "could not communicate with IMDS: {}",
- DisplayErrorContext(&err)
- )))
+ Err(ImdsError::FailedToLoadToken(err @ SdkError::DispatchFailure(_))) => {
+ Err(CredentialsError::not_loaded(ImdsCommunicationError {
+ source: err.into(),
+ }))
  }
  Err(other) => Err(CredentialsError::provider_error(other)),
  }

aws/rust-runtime/aws-sig-auth/src/middleware.rs

@@ -97,9 +97,13 @@ impl Display for SigningStageError {
 
 impl Error for SigningStageError {
  fn source(&self) -> Option<&(dyn Error + 'static)> {
+ use SigningStageErrorKind as ErrorKind;
  match &self.kind {
- SigningStageErrorKind::SigningFailure(err) => Some(err),
- _ => None,
+ ErrorKind::SigningFailure(err) => Some(err),
+ ErrorKind::MissingCredentials
+ | ErrorKind::MissingSigningRegion
+ | ErrorKind::MissingSigningService
+ | ErrorKind::MissingSigningConfig => None,
  }
  }
 }