add kitsune-error crate

Cargo.toml

@@ -24,6 +24,7 @@ members = [
     "crates/kitsune-db",
     "crates/kitsune-email",
     "crates/kitsune-embed",
+    "crates/kitsune-error",
     "crates/kitsune-federation",
     "crates/kitsune-federation-filter",
     "crates/kitsune-http-client",

crates/kitsune-error/Cargo.toml

@@ -0,0 +1,15 @@
+[package]
+name = "kitsune-error"
+authors.workspace = true
+edition.workspace = true
+version.workspace = true
+license.workspace = true
+
+[dependencies]
+axum-core = "0.4.3"
+eyre = "0.6.12"
+http = "1.1.0"
+tracing = "0.1.40"
+
+[lints]
+workspace = true

crates/kitsune-error/src/axum.rs

@@ -0,0 +1,27 @@
+use crate::{Error, ErrorType};
+use axum_core::response::{IntoResponse, Response};
+use http::StatusCode;
+
+#[inline]
+fn to_response<B>(status_code: StatusCode, maybe_body: Option<B>) -> Response
+where
+    B: IntoResponse,
+{
+    maybe_body.map_or_else(
+        || status_code.into_response(),
+        |body| (status_code, body).into_response(),
+    )
+}
+
+impl IntoResponse for Error {
+    fn into_response(self) -> Response {
+        debug!(error = ?self.inner);
+
+        match self.ty {
+            ErrorType::BadRequest(maybe_body) => to_response(StatusCode::BAD_REQUEST, maybe_body),
+            ErrorType::NotFound => StatusCode::NOT_FOUND.into_response(),
+            ErrorType::Unauthorized => StatusCode::UNAUTHORIZED.into_response(),
+            ErrorType::Other => StatusCode::INTERNAL_SERVER_ERROR.into_response(),
+        }
+    }
+}

crates/kitsune-error/src/ext.rs

@@ -0,0 +1,24 @@
+use crate::{Error, ErrorType};
+
+mod sealed {
+    pub trait Sealed {}
+
+    impl<T, E> Sealed for Result<T, E> {}
+}
+
+pub trait ResultExt<T>: sealed::Sealed {
+    fn with_error_type(self, ty: ErrorType) -> Result<T, Error>;
+}
+
+impl<T, E> ResultExt<T> for Result<T, E>
+where
+    E: Into<eyre::Report>,
+{
+    #[inline]
+    fn with_error_type(self, ty: ErrorType) -> Result<T, Error> {
+        self.map_err(|err| Error {
+            ty,
+            inner: err.into(),
+        })
+    }
+}

crates/kitsune-error/src/lib.rs

@@ -0,0 +1,58 @@
+#[macro_use]
+extern crate tracing;
+
+pub use self::ext::ResultExt;
+
+mod axum;
+mod ext;
+
+#[derive(Clone)]
+pub enum ErrorType {
+    BadRequest(Option<String>),
+    NotFound,
+    Unauthorized,
+    Other,
+}
+
+pub struct Error {
+    ty: ErrorType,
+    inner: eyre::Report,
+}
+
+impl Error {
+    pub fn new<E>(ty: ErrorType, err: E) -> Self
+    where
+        E: Into<eyre::Report>,
+    {
+        Self {
+            ty,
+            inner: err.into(),
+        }
+    }
+
+    #[must_use]
+    pub fn error_type(&self) -> &ErrorType {
+        &self.ty
+    }
+
+    pub fn error(&self) -> &eyre::Report {
+        &self.inner
+    }
+
+    #[must_use]
+    pub fn with_error_type(self, ty: ErrorType) -> Self {
+        Self { ty, ..self }
+    }
+}
+
+impl<T> From<T> for Error
+where
+    T: Into<eyre::Report>,
+{
+    fn from(value: T) -> Self {
+        Self {
+            ty: ErrorType::Other,
+            inner: value.into(),
+        }
+    }
+}