ch9: refactor

Signed-off-by: Jin Dong <djdongjin95@gmail.com>

src/domain/newsletter.rs

@@ -1,8 +1,9 @@
+use crate::domain::SubscriberEmail;
+use crate::{email_client::EmailClient, routes::error_chain_fmt};
 use actix_web::{http::StatusCode, web, HttpResponse, ResponseError};
+use anyhow::Context;
 use sqlx::PgPool;
 
-use crate::routes::error_chain_fmt;
-
 #[derive(serde::Deserialize)]
 pub struct BodyData {
     title: String,
@@ -15,10 +16,6 @@ pub struct Content {
     text: String,
 }
 
-struct ConfirmedSubscriber {
-    email: String,
-}
-
 #[derive(thiserror::Error)]
 pub enum PublishError {
     #[error(transparent)]
@@ -41,25 +38,56 @@ impl ResponseError for PublishError {
 }
 
 pub async fn publish_newsletter(
-    _body: web::Json<BodyData>,
+    body: web::Json<BodyData>,
     pool: web::Data<PgPool>,
+    email_client: web::Data<EmailClient>,
 ) -> Result<HttpResponse, PublishError> {
-    let _subscribers = get_confirmed_subscribers(&pool).await?;
+    let subscribers = get_confirmed_subscribers(&pool).await?;
+
+    for sub in subscribers {
+        match sub {
+            Ok(sub) => {
+                email_client
+                    .send_email(
+                        &sub.email,
+                        &body.title,
+                        &body.content.html,
+                        &body.content.text,
+                    )
+                    .await
+                    .with_context(|| format!("Failed to send email to {}", sub.email))?;
+            }
+            Err(error) => {
+                tracing::warn!(
+                    error.cause_chain = ?error,
+                    "Skip a confirmed subscriber. \
+                    Their stored contact details are invalid",
+                );
+            }
+        }
+    }
 
     Ok(HttpResponse::Ok().finish())
 }
 
+struct ConfirmedSubscriber {
+    email: SubscriberEmail,
+}
+
 #[tracing::instrument(name = "Get confirmed subscribers", skip(pool))]
 async fn get_confirmed_subscribers(
     pool: &PgPool,
-) -> Result<Vec<ConfirmedSubscriber>, anyhow::Error> {
-    // `query_as` maps results to the type specified as its first argument.
-    let confirmed_subscribers = sqlx::query_as!(
-        ConfirmedSubscriber,
-        r#"SELECT email FROM subscriptions WHERE status = 'confirmed'"#
-    )
-    .fetch_all(pool)
-    .await?;
+) -> Result<Vec<Result<ConfirmedSubscriber, anyhow::Error>>, anyhow::Error> {
+    let confirmed_subscribers =
+        sqlx::query!(r#"SELECT email FROM subscriptions WHERE status = 'confirmed'"#)
+            .fetch_all(pool)
+            .await?
+            .into_iter()
+            .map(|r| match SubscriberEmail::parse(r.email) {
+                Ok(email) => Ok(ConfirmedSubscriber { email }),
+                Err(error) => Err(anyhow::anyhow!(error)),
+            })
+            .collect();
 
     Ok(confirmed_subscribers)
 }

src/domain/subscriber_email.rs

@@ -20,6 +20,12 @@ impl AsRef<str> for SubscriberEmail {
     }
 }
 
+impl std::fmt::Display for SubscriberEmail {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        self.0.fmt(f)
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::SubscriberEmail;

src/email_client.rs

@@ -39,7 +39,7 @@ impl EmailClient {
 
     pub async fn send_email(
         &self,
-        recipient: SubscriberEmail,
+        recipient: &SubscriberEmail,
         subject: &str,
         html_content: &str,
         text_content: &str,
@@ -144,7 +144,7 @@ mod tests {
 
         // Act
         let _ = email_client
-            .send_email(email(), &subject(), &content(), &content())
+            .send_email(&email(), &subject(), &content(), &content())
             .await;
 
         // Assert via the mounted `Mock`.
@@ -164,7 +164,7 @@ mod tests {
 
         // Act
         let outcome = email_client
-            .send_email(email(), &subject(), &content(), &content())
+            .send_email(&email(), &subject(), &content(), &content())
             .await;
 
         // Assert
@@ -186,7 +186,7 @@ mod tests {
 
         // Act
         let outcome = email_client
-            .send_email(email(), &subject(), &content(), &content())
+            .send_email(&email(), &subject(), &content(), &content())
             .await;
 
         // Assert
@@ -208,7 +208,7 @@ mod tests {
 
         // Act
         let outcome = email_client
-            .send_email(email(), &subject(), &content(), &content())
+            .send_email(&email(), &subject(), &content(), &content())
             .await;
 
         // Assert

src/routes/subscriptions.rs

@@ -149,7 +149,7 @@ pub async fn send_confirmation_email(
     );
 
     email_client
-        .send_email(form.email, "welcome", &html_body, &plain_body)
+        .send_email(&form.email, "welcome", &html_body, &plain_body)
         .await
 }