api: better handling of helper errors to distinguish error codes

src/api/s3/api_server.rs

@@ -150,7 +150,8 @@ impl ApiHandler for S3ApiServer {
 		let bucket_id = garage
 			.bucket_helper()
 			.resolve_bucket(&bucket_name, &api_key)
-			.await?;
+			.await
+			.map_err(pass_helper_error)?;
 		let bucket = garage
 			.bucket_helper()
 			.get_existing_bucket(bucket_id)

src/api/s3/copy.rs

@@ -655,7 +655,8 @@ async fn get_copy_source(ctx: &ReqCtx, req: &Request<ReqBody>) -> Result<Object,
 	let source_bucket_id = garage
 		.bucket_helper()
 		.resolve_bucket(&source_bucket.to_string(), api_key)
-		.await?;
+		.await
+		.map_err(pass_helper_error)?;
 
 	if !api_key.allow_read(&source_bucket_id) {
 		return Err(Error::forbidden(format!(

src/api/s3/cors.rs

@@ -1,6 +1,7 @@
-use quick_xml::de::from_reader;
 use std::sync::Arc;
 
+use quick_xml::de::from_reader;
+
 use http::header::{
 	ACCESS_CONTROL_ALLOW_HEADERS, ACCESS_CONTROL_ALLOW_METHODS, ACCESS_CONTROL_ALLOW_ORIGIN,
 	ACCESS_CONTROL_EXPOSE_HEADERS, ACCESS_CONTROL_REQUEST_HEADERS, ACCESS_CONTROL_REQUEST_METHOD,
@@ -14,7 +15,7 @@ use http_body_util::BodyExt;
 
 use serde::{Deserialize, Serialize};
 
-use crate::common_error::CommonError;
+use crate::common_error::{helper_error_as_internal, CommonError};
 use crate::helpers::*;
 use crate::s3::api_server::{ReqBody, ResBody};
 use crate::s3::error::*;
@@ -116,9 +117,16 @@ pub async fn handle_options_api(
 	// OPTIONS calls are not auhtenticated).
 	if let Some(bn) = bucket_name {
 		let helper = garage.bucket_helper();
-		let bucket_id = helper.resolve_global_bucket_name(&bn).await?;
+		let bucket_id = helper
+			.resolve_global_bucket_name(&bn)
+			.await
+			.map_err(helper_error_as_internal)?;
 		if let Some(id) = bucket_id {
-			let bucket = garage.bucket_helper().get_existing_bucket(id).await?;
+			let bucket = garage
+				.bucket_helper()
+				.get_existing_bucket(id)
+				.await
+				.map_err(helper_error_as_internal)?;
 			let bucket_params = bucket.state.into_option().unwrap();
 			handle_options_for_bucket(req, &bucket_params)
 		} else {

src/api/s3/error.rs

@@ -4,7 +4,10 @@ use err_derive::Error;
 use hyper::header::HeaderValue;
 use hyper::{HeaderMap, StatusCode};
 
-use crate::common_error::CommonError;
+use garage_model::helper::error::Error as HelperError;
+
+pub(crate) use crate::common_error::pass_helper_error;
+use crate::common_error::{helper_error_as_internal, CommonError};
 pub use crate::common_error::{CommonErrorDerivative, OkOrBadRequest, OkOrInternalError};
 use crate::generic_server::ApiError;
 use crate::helpers::*;
@@ -87,6 +90,14 @@ where
 	}
 }
 
+// Helper errors are always passed as internal errors by default.
+// To pass the specific error code back to the client, use `pass_helper_error`.
+impl From<HelperError> for Error {
+	fn from(err: HelperError) -> Error {
+		Error::Common(helper_error_as_internal(err))
+	}
+}
+
 impl CommonErrorDerivative for Error {}
 
 impl From<roxmltree::Error> for Error {

src/api/s3/post_object.rs

@@ -107,7 +107,8 @@ pub async fn handle_post_object(
 	let bucket_id = garage
 		.bucket_helper()
 		.resolve_bucket(&bucket_name, &api_key)
-		.await?;
+		.await
+		.map_err(pass_helper_error)?;
 
 	if !api_key.allow_write(&bucket_id) {
 		return Err(Error::forbidden("Operation is not allowed for this key."));