controllers/user/update: Reduce spawn_blocking() scope (#9879)

The email sending code is still sync and needs to be in a `spawn_blocking()` block for now, but the rest of the `regenerate_token_and_send()` can be converted to use async database queries.

Author: Turbo87

src/controllers/user/resend.rs

@@ -4,14 +4,15 @@ use crate::auth::AuthCheck;
 use crate::controllers::helpers::ok_true;
 use crate::models::Email;
 use crate::tasks::spawn_blocking;
-use crate::util::errors::bad_request;
 use crate::util::errors::AppResult;
+use crate::util::errors::{bad_request, BoxedAppError};
 use axum::extract::Path;
 use axum::response::Response;
 use crates_io_database::schema::emails;
 use diesel::dsl::sql;
 use diesel::prelude::*;
-use diesel_async::async_connection_wrapper::AsyncConnectionWrapper;
+use diesel_async::scoped_futures::ScopedFutureExt;
+use diesel_async::{AsyncConnection, RunQueryDsl};
 use http::request::Parts;
 
 /// Handles `PUT /user/:user_id/resend` route
@@ -22,35 +23,40 @@ pub async fn regenerate_token_and_send(
 ) -> AppResult<Response> {
     let mut conn = state.db_write().await?;
     let auth = AuthCheck::default().check(&req, &mut conn).await?;
-    spawn_blocking(move || {
-        let conn: &mut AsyncConnectionWrapper<_> = &mut conn.into();
 
-        let user = auth.user();
-
-        // need to check if current user matches user to be updated
-        if user.id != param_user_id {
-            return Err(bad_request("current user does not match requested user"));
-        }
+    // need to check if current user matches user to be updated
+    if auth.user_id() != param_user_id {
+        return Err(bad_request("current user does not match requested user"));
+    }
 
-        conn.transaction(|conn| -> AppResult<_> {
-            let email: Email = diesel::update(Email::belonging_to(user))
+    conn.transaction(|conn| {
+        async move {
+            let email: Email = diesel::update(Email::belonging_to(auth.user()))
                 .set(emails::token.eq(sql("DEFAULT")))
                 .get_result(conn)
+                .await
                 .optional()?
                 .ok_or_else(|| bad_request("Email could not be found"))?;
 
-            let email1 = UserConfirmEmail {
-                user_name: &user.gh_login,
-                domain: &state.emails.domain,
-                token: email.token,
-            };
-
-            state.emails.send(&email.email, email1).map_err(Into::into)
-        })?;
-
-        ok_true()
+            spawn_blocking(move || {
+                let email1 = UserConfirmEmail {
+                    user_name: &auth.user().gh_login,
+                    domain: &state.emails.domain,
+                    token: email.token,
+                };
+
+                state
+                    .emails
+                    .send(&email.email, email1)
+                    .map_err(BoxedAppError::from)
+            })
+            .await
+        }
+        .scope_boxed()
     })
-    .await
+    .await?;
+
+    ok_true()
 }
 
 #[cfg(test)]