Refactor emails to be async

backend/Cargo.lock

@@ -1192,10 +1192,12 @@ version = "0.10.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "76bd09637ae3ec7bd605b8e135e757980b3968430ff2b1a4a94fb7769e50166d"
 dependencies = [
+ "async-trait",
  "base64 0.21.0",
  "email-encoding",
  "email_address",
  "fastrand",
+ "futures-io",
  "futures-util",
  "hostname",
  "httpdate",
@@ -1207,6 +1209,7 @@ dependencies = [
  "quoted_printable",
  "socket2",
  "tokio",
+ "tokio-native-tls",
 ]
 
 [[package]]

backend/Cargo.toml

@@ -9,7 +9,7 @@ actix-web = "4.3.1"
 anyhow = "1.0.70"
 chrono = "0.4.24"
 flexi_logger = "0.25.3"
-lettre = "0.10.4"
+lettre = { version = "0.10.4", features = ["tokio1-native-tls"] }
 log = "0.4.17"
 once_cell = "1.17.1"
 rand = "0.8.5"

backend/src/confirmation.rs

@@ -9,7 +9,7 @@ use crate::utils::{extract_domain, get_email_from_cert, parse_pem, read_file};
 use crate::{log_err, pending_path};
 use anyhow::Result;
 
-use lettre::{Message, Transport};
+use lettre::{AsyncTransport, Message};
 use std::fs;
 use std::path::Path;
 
@@ -43,7 +43,7 @@ pub fn confirm_action(token: &str) -> Result<(Action, String)> {
     }
 }
 
-pub fn send_confirmation_email(address: &str, action: &Action, token: &str) -> Result<()> {
+pub async fn send_confirmation_email(address: &str, action: &Action, token: &str) -> Result<()> {
     let template = log_err!(
         read_file(&Path::new("assets").join("mail-template.html")),
         error,
@@ -82,7 +82,7 @@ pub fn send_confirmation_email(address: &str, action: &Action, token: &str) -> R
 
     let email = log_err!(email, warn)?;
 
-    match log_err!(MAILER.send(&email), warn) {
+    match log_err!(MAILER.send(email).await, warn) {
         Ok(_) => Ok(()),
         Err(_) => Err(SpecialErrors::MailErr)?,
     }

backend/src/main.rs

@@ -110,7 +110,7 @@ async fn submit(pem: web::Form<Key>) -> Result<HttpResponse, CompatErr> {
         "Sending email to {} to add a key... (Request token: {})",
         email, token
     );
-    send_confirmation_email(&email, &Action::Add, &token)?;
+    send_confirmation_email(&email, &Action::Add, &token).await?;
     info!("User {} requested to add a key successfully!", email);
     Ok(return_outcome(Ok("You submitted your key successfully!"))?)
 }
@@ -140,7 +140,7 @@ async fn delete(email: web::Query<Email>) -> Result<HttpResponse, CompatErr> {
         "Sending email to {} to delete a key... (Request token: {})",
         email.email, token
     );
-    send_confirmation_email(&email.email, &Action::Delete, &token)?;
+    send_confirmation_email(&email.email, &Action::Delete, &token).await?;
     info!(
         "User {} requested to delete his key successfully!",
         email.email

backend/src/settings.rs

@@ -1,5 +1,5 @@
-use lettre::{transport::smtp::authentication::Credentials, SmtpTransport};
-use log::{debug, error, warn};
+use lettre::{transport::smtp::authentication::Credentials, AsyncSmtpTransport, Tokio1Executor};
+use log::{debug, error};
 use once_cell::sync::Lazy;
 use sequoia_net::wkd::Variant;
 use sequoia_openpgp::policy::StandardPolicy;
@@ -65,16 +65,18 @@ fn get_settings() -> Settings {
     settings
 }
 
-fn get_mailer() -> SmtpTransport {
+fn get_mailer() -> AsyncSmtpTransport<Tokio1Executor> {
     debug!("Setting up smtp...");
     let creds = Credentials::new(
         SETTINGS.mail_settings.smtp_username.to_owned(),
         SETTINGS.mail_settings.smtp_password.to_owned(),
     );
     let builder = match &SETTINGS.mail_settings.smtp_tls {
-        SMTPEncryption::Tls => SmtpTransport::relay(&SETTINGS.mail_settings.smtp_host),
+        SMTPEncryption::Tls => {
+            AsyncSmtpTransport::<Tokio1Executor>::relay(&SETTINGS.mail_settings.smtp_host)
+        }
         SMTPEncryption::Starttls => {
-            SmtpTransport::starttls_relay(&SETTINGS.mail_settings.smtp_host)
+            AsyncSmtpTransport::<Tokio1Executor>::starttls_relay(&SETTINGS.mail_settings.smtp_host)
         }
     };
     let mailer = match builder {
@@ -87,8 +89,6 @@ fn get_mailer() -> SmtpTransport {
     .credentials(creds)
     .port(SETTINGS.mail_settings.smtp_port)
     .build();
-    debug!("Testing smtp connection...");
-    let _ = log_err!(mailer.test_connection(), warn);
     mailer
 }
 
@@ -96,4 +96,4 @@ pub const ERROR_TEXT: &str = "An error occoured:";
 pub const POLICY: &StandardPolicy = &StandardPolicy::new();
 pub const ROOT_FOLDER: &str = "data";
 pub static SETTINGS: Lazy<Settings> = Lazy::new(get_settings);
-pub static MAILER: Lazy<SmtpTransport> = Lazy::new(get_mailer);
+pub static MAILER: Lazy<AsyncSmtpTransport<Tokio1Executor>> = Lazy::new(get_mailer);