Refactor admin routes to use new AppError struct in responses

src/routes.rs

@@ -8,7 +8,10 @@ mod subscriptions_confirm;
 
 pub use admin::*;
 use askama::Template;
-use axum::response::{Html, IntoResponse, Response};
+use axum::{
+    http::HeaderMap,
+    response::{Html, IntoResponse, Response},
+};
 pub use health_check::*;
 pub use home::*;
 pub use login::*;
@@ -17,6 +20,62 @@ use reqwest::StatusCode;
 pub use subscriptions::*;
 pub use subscriptions_confirm::*;
 
+use crate::templates::MessageTemplate;
+
+#[derive(thiserror::Error)]
+pub enum AppError {
+    #[error("An unexpected error was encountered.")]
+    UnexpectedError(#[from] anyhow::Error),
+    #[error("A validation error happened.")]
+    ValidationError(#[source] anyhow::Error),
+    #[error("An authentication is required.")]
+    NotAuthenticated,
+}
+
+impl std::fmt::Debug for AppError {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        error_chain_fmt(self, f)
+    }
+}
+
+impl IntoResponse for AppError {
+    fn into_response(self) -> Response {
+        tracing::error!("{:?}", self);
+
+        match &self {
+            AppError::UnexpectedError(_) => {
+                let template = MessageTemplate::Error {
+                    message: "An internal server error occured.".into(),
+                };
+                Html(template.render().unwrap()).into_response()
+            }
+            AppError::ValidationError(error) => {
+                let template = MessageTemplate::Error {
+                    message: error.to_string(),
+                };
+                Html(template.render().unwrap()).into_response()
+            }
+            AppError::NotAuthenticated => {
+                let mut headers = HeaderMap::new();
+                headers.insert("HX-Redirect", "/login".parse().unwrap());
+                (StatusCode::UNAUTHORIZED, headers).into_response()
+            }
+        }
+    }
+}
+
+impl From<AdminError> for AppError {
+    fn from(value: AdminError) -> Self {
+        match value {
+            AdminError::UnexpectedError(error) => AppError::UnexpectedError(error),
+            AdminError::NotAuthenticated => AppError::NotAuthenticated,
+            AdminError::ChangePassword(s) => AppError::ValidationError(anyhow::anyhow!(s)),
+            AdminError::Publish(e) => AppError::ValidationError(e),
+            AdminError::Idempotency(s) => AppError::UnexpectedError(anyhow::anyhow!(s)),
+        }
+    }
+}
+
 #[derive(Template)]
 #[template(path = "../templates/404.html")]
 struct NotFoundTemplate;