Common error type and admin error type that uses it

src/api/common_error.rs

@@ -0,0 +1,108 @@
+use err_derive::Error;
+use hyper::header::HeaderValue;
+use hyper::{Body, HeaderMap, StatusCode};
+
+use garage_model::helper::error::Error as HelperError;
+use garage_util::error::Error as GarageError;
+
+use crate::generic_server::ApiError;
+
+/// Errors of this crate
+#[derive(Debug, Error)]
+pub enum CommonError {
+	// Category: internal error
+	/// Error related to deeper parts of Garage
+	#[error(display = "Internal error: {}", _0)]
+	InternalError(#[error(source)] GarageError),
+
+	/// Error related to Hyper
+	#[error(display = "Internal error (Hyper error): {}", _0)]
+	Hyper(#[error(source)] hyper::Error),
+
+	/// Error related to HTTP
+	#[error(display = "Internal error (HTTP error): {}", _0)]
+	Http(#[error(source)] http::Error),
+
+	/// The client sent an invalid request
+	#[error(display = "Bad request: {}", _0)]
+	BadRequest(String),
+}
+
+impl CommonError {
+	pub fn http_status_code(&self) -> StatusCode {
+		match self {
+			CommonError::InternalError(
+				GarageError::Timeout
+				| GarageError::RemoteError(_)
+				| GarageError::Quorum(_, _, _, _),
+			) => StatusCode::SERVICE_UNAVAILABLE,
+			CommonError::InternalError(_) | CommonError::Hyper(_) | CommonError::Http(_) => 
+				StatusCode::INTERNAL_SERVER_ERROR,
+			CommonError::BadRequest(_) => StatusCode::BAD_REQUEST,
+		}
+	}
+}
+
+/// Trait to map error to the Bad Request error code
+pub trait OkOrBadRequest {
+	type S;
+	fn ok_or_bad_request<M: AsRef<str>>(self, reason: M) -> Result<Self::S, CommonError>;
+}
+
+impl<T, E> OkOrBadRequest for Result<T, E>
+where
+	E: std::fmt::Display,
+{
+	type S = T;
+	fn ok_or_bad_request<M: AsRef<str>>(self, reason: M) -> Result<T, CommonError> {
+		match self {
+			Ok(x) => Ok(x),
+			Err(e) => Err(CommonError::BadRequest(format!("{}: {}", reason.as_ref(), e))),
+		}
+	}
+}
+
+impl<T> OkOrBadRequest for Option<T> {
+	type S = T;
+	fn ok_or_bad_request<M: AsRef<str>>(self, reason: M) -> Result<T, CommonError> {
+		match self {
+			Some(x) => Ok(x),
+			None => Err(CommonError::BadRequest(reason.as_ref().to_string())),
+		}
+	}
+}
+
+/// Trait to map an error to an Internal Error code
+pub trait OkOrInternalError {
+	type S;
+	fn ok_or_internal_error<M: AsRef<str>>(self, reason: M) -> Result<Self::S, CommonError>;
+}
+
+impl<T, E> OkOrInternalError for Result<T, E>
+where
+	E: std::fmt::Display,
+{
+	type S = T;
+	fn ok_or_internal_error<M: AsRef<str>>(self, reason: M) -> Result<T, CommonError> {
+		match self {
+			Ok(x) => Ok(x),
+			Err(e) => Err(CommonError::InternalError(GarageError::Message(format!(
+				"{}: {}",
+				reason.as_ref(),
+				e
+			)))),
+		}
+	}
+}
+
+impl<T> OkOrInternalError for Option<T> {
+	type S = T;
+	fn ok_or_internal_error<M: AsRef<str>>(self, reason: M) -> Result<T, CommonError> {
+		match self {
+			Some(x) => Ok(x),
+			None => Err(CommonError::InternalError(GarageError::Message(
+				reason.as_ref().to_string(),
+			))),
+		}
+	}
+}