refactor: clean up subscription

src/routes/subscriptions.rs

@@ -1,5 +1,6 @@
 use crate::domain::SubscriberEmail;
 use crate::domain::{NewSubscriber, SubscriberName};
+use crate::email_client::EmailClient;
 use crate::startup::AppState;
 use axum::extract::State;
 use axum::routing::post;
@@ -30,6 +31,29 @@ impl TryFrom<FormData> for NewSubscriber {
     }
 }
 
+#[tracing::instrument(
+    name = "Send a confirmation email to a new subscriber",
+    skip(email_client, new_subscriber)
+)]
+pub async fn send_confirmation_email(
+    email_client: &EmailClient,
+    new_subscriber: NewSubscriber,
+) -> Result<(), reqwest::Error> {
+    let confirmation_link = "https://my-api.com/subscriptions/confirm";
+    let plain_body = format!(
+        "Welcome to our newsletter! Visit {} to confirm your subscription.",
+        confirmation_link
+    );
+    let html_body = format!(
+        "Welcome to our newsletter!<br />\
+        Click <a href=\"{}\">here</a> to confirm your subscription.",
+        confirmation_link
+    );
+    email_client
+        .send_email(new_subscriber.email, "Welcome!", &html_body, &plain_body)
+        .await
+}
+
 // TODO: remove request_id?
 #[tracing::instrument(
     name = "Adding a new subscriber",
@@ -56,21 +80,7 @@ pub async fn subscribe(
     if insert_subscriber(&db_pool, &new_subscriber).await.is_err() {
         return (StatusCode::INTERNAL_SERVER_ERROR, "Something went wrong.").into_response();
     }
-    let confirmation_link = "https://my-api.com/subscriptions/confirm";
-    if email_client
-        .send_email(
-            new_subscriber.email,
-            "Welcome!",
-            &format!(
-                "Welcome to our newsletter!<br />\
-                Click <a href=\"{}\">here</a> to confirm your subscription.",
-                confirmation_link,
-            ),
-            &format!(
-                "Welcome to our newsletter! \nVisit {} to confirm your subscription.",
-                confirmation_link,
-            ),
-        )
+    if send_confirmation_email(&email_client, new_subscriber)
         .await
         .is_err()
     {