From 90fc6abf19245c2063b5431e0e28fc6f31f9471f Mon Sep 17 00:00:00 2001
From: Sandro Eiler <sandro.eiler@posteo.de>
Date: Tue, 5 Mar 2024 10:12:34 +0100
Subject: [PATCH] feat: add confirmation link to email

---
 Cargo.lock                  | 10 ++++++++++
 Cargo.toml                  |  6 +-----
 src/routes/subscriptions.rs | 12 ++++++++++--
 tests/api/subscriptions.rs  | 35 +++++++++++++++++++++++++++++++++++
 4 files changed, 56 insertions(+), 7 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 14bb877..6ae4c9e 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1112,6 +1112,7 @@ dependencies = [
  "config",
  "fake",
  "hyper 1.2.0",
+ "linkify",
  "once_cell",
  "quickcheck",
  "quickcheck_macros",
@@ -1165,6 +1166,15 @@ version = "0.5.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0717cef1bc8b636c6e1c1bbdefc09e6322da8a9321966e8928ef80d20f7f770f"
 
+[[package]]
+name = "linkify"
+version = "0.10.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f1dfa36d52c581e9ec783a7ce2a5e0143da6237be5811a0b3153fedfdbe9f780"
+dependencies = [
+ "memchr",
+]
+
 [[package]]
 name = "linux-raw-sys"
 version = "0.3.8"
diff --git a/Cargo.toml b/Cargo.toml
index 5c621aa..fe81084 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -19,12 +19,10 @@ hyper = { version = "1.2.0", features = ["full"] }
 serde = { version = "1.0", features = ["derive"] }
 serde_json = "1"
 serde-aux = "4"
-# serde_with = "3"
 # Axum
 axum = { version = "0.7" }
 tower = { version = "0.4" }
 tower-http = { version = "0.5", features = ["trace", "request-id", "util"] }
-# tower-cookies = "0.10"
 # Others
 config = "0.14"
 uuid = { version = "1", features = ["v4", "fast-rng"] }
@@ -38,9 +36,6 @@ unicode-segmentation = "1"
 strum_macros = "0.26"
 validator = "0.16"
 
-# async-trait = "0.1"
-# strum_macros = "0.25"
-
 [dependencies.sqlx]
 version = "0.7"
 default-features = false
@@ -68,3 +63,4 @@ quickcheck_macros = "1.0.0"
 rand = "0.8.5"
 wiremock = "0.6.0"
 serde_json = "1"
+linkify = "0.10"
diff --git a/src/routes/subscriptions.rs b/src/routes/subscriptions.rs
index 6dd1fbb..7167657 100644
--- a/src/routes/subscriptions.rs
+++ b/src/routes/subscriptions.rs
@@ -56,12 +56,20 @@ 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!",
-            "Welcome to our newsletter!",
-            "Welcome to our newsletter!",
+            &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,
+            ),
         )
         .await
         .is_err()
diff --git a/tests/api/subscriptions.rs b/tests/api/subscriptions.rs
index bfa8587..e9bae61 100644
--- a/tests/api/subscriptions.rs
+++ b/tests/api/subscriptions.rs
@@ -2,6 +2,41 @@ use crate::helpers::spawn_app;
 use wiremock::matchers::{method, path};
 use wiremock::{Mock, ResponseTemplate};
 
+#[tokio::test]
+async fn subscribe_sends_a_confirmation_email_with_a_link() {
+    //Arrange
+    let app = spawn_app().await;
+    let body = "name=le%20guin&email=ursula_le_guin%40gmail.com";
+
+    Mock::given(path("/email"))
+        .and(method("POST"))
+        .respond_with(ResponseTemplate::new(200))
+        .mount(&app.email_server)
+        .await;
+
+    // Act
+    app.post_subscriptions(body.into()).await;
+
+    // Assert
+    // Get the first intercepted request
+    let email_request = &app.email_server.received_requests().await.unwrap()[0];
+    // Parse the body as JSON, starting from raw bytes
+    let body: serde_json::Value = serde_json::from_slice(&email_request.body).unwrap();
+    // Extract the link from one of the request fields.
+    let get_link = |s: &str| {
+        let links: Vec<_> = linkify::LinkFinder::new()
+            .links(s)
+            .filter(|l| *l.kind() == linkify::LinkKind::Url)
+            .collect();
+        assert_eq!(links.len(), 1);
+        links[0].as_str().to_owned()
+    };
+    let html_link = get_link(body["HtmlBody"].as_str().unwrap());
+    let text_link = get_link(body["TextBody"].as_str().unwrap());
+    // The two links should be identical
+    assert_eq!(html_link, text_link);
+}
+
 #[tokio::test]
 async fn subscribe_sends_a_confirmation_email_for_valid_data() {
     // Arrange