feat: add email client

Cargo.lock

@@ -60,6 +60,16 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "assert-json-diff"
+version = "2.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "47e4f2b81832e72834d7518d8487a0396a28cc408186a2e8854c0f98011faf12"
+dependencies = [
+ "serde",
+ "serde_json",
+]
+
 [[package]]
 name = "async-trait"
 version = "0.1.68"
@@ -374,6 +384,24 @@ dependencies = [
  "typenum",
 ]
 
+[[package]]
+name = "deadpool"
+version = "0.10.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fb84100978c1c7b37f09ed3ce3e5f843af02c2a2c431bae5b19230dad2c1b490"
+dependencies = [
+ "async-trait",
+ "deadpool-runtime",
+ "num_cpus",
+ "tokio",
+]
+
+[[package]]
+name = "deadpool-runtime"
+version = "0.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "63dfa964fe2a66f3fde91fc70b267fe193d822c7e603e2a675a49a7f46ad3f49"
+
 [[package]]
 name = "der"
 version = "0.7.8"
@@ -550,6 +578,21 @@ dependencies = [
  "percent-encoding",
 ]
 
+[[package]]
+name = "futures"
+version = "0.3.28"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "23342abe12aba583913b2e62f22225ff9c950774065e4bfb61a19cd9770fec40"
+dependencies = [
+ "futures-channel",
+ "futures-core",
+ "futures-executor",
+ "futures-io",
+ "futures-sink",
+ "futures-task",
+ "futures-util",
+]
+
 [[package]]
 name = "futures-channel"
 version = "0.3.28"
@@ -594,6 +637,17 @@ version = "0.3.30"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a44623e20b9681a318efdd71c299b6b222ed6f231972bfe2f224ebad6311f0c1"
 
+[[package]]
+name = "futures-macro"
+version = "0.3.28"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "89ca545a94061b6365f2c7355b4b32bd20df3ff95f02da9329b34ccc3bd6ee72"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.32",
+]
+
 [[package]]
 name = "futures-sink"
 version = "0.3.28"
@@ -612,8 +666,10 @@ version = "0.3.28"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "26b01e40b772d54cf6c6d721c1d1abd0647a0106a12ecaa1c186273392a69533"
 dependencies = [
+ "futures-channel",
  "futures-core",
  "futures-io",
+ "futures-macro",
  "futures-sink",
  "futures-task",
  "memchr",
@@ -1076,6 +1132,7 @@ dependencies = [
  "unicode-segmentation",
  "uuid",
  "validator",
+ "wiremock",
 ]
 
 [[package]]
@@ -3007,6 +3064,30 @@ dependencies = [
  "winapi",
 ]
 
+[[package]]
+name = "wiremock"
+version = "0.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ec874e1eef0df2dcac546057fe5e29186f09c378181cd7b635b4b7bcc98e9d81"
+dependencies = [
+ "assert-json-diff",
+ "async-trait",
+ "base64",
+ "deadpool",
+ "futures",
+ "http 1.0.0",
+ "http-body-util",
+ "hyper 1.1.0",
+ "hyper-util",
+ "log",
+ "once_cell",
+ "regex",
+ "serde",
+ "serde_json",
+ "tokio",
+ "url",
+]
+
 [[package]]
 name = "yaml-rust"
 version = "0.4.5"

Cargo.toml

@@ -59,9 +59,11 @@ default-features = false
 features = ["json", "rustls-tls"]
 
 [dev-dependencies]
+tokio = { version = "1", features = ["rt", "macros"] }
 once_cell = "1"
 claims = "0.7"
 fake = "2.9.2"
 quickcheck = "1.0.3"
 quickcheck_macros = "1.0.0"
 rand = "0.8.5"
+wiremock = "0.6.0"

configuration/base.yaml

@@ -9,3 +9,4 @@ database:
 email_client:
   base_url: "localhost"
   sender_email: "test@fmail.com"
+  authorization_token: "my-secret-token"

src/configuration.rs

@@ -21,6 +21,7 @@ pub struct Settings {
 pub struct EmailClientSettings {
     pub base_url: String,
     pub sender_email: String,
+    pub authorization_token: Secret<String>,
 }
 
 impl EmailClientSettings {

src/email_client.rs

@@ -1,19 +1,26 @@
 use crate::domain::SubscriberEmail;
 use reqwest::Client;
+use secrecy::{ExposeSecret, Secret};
 
 #[derive(Clone)]
 pub struct EmailClient {
     http_client: Client,
     base_url: String,
     sender: SubscriberEmail,
+    authorization_token: Secret<String>,
 }
 
 impl EmailClient {
-    pub fn new(base_url: String, sender: SubscriberEmail) -> Self {
+    pub fn new(
+        base_url: String,
+        sender: SubscriberEmail,
+        authorization_token: Secret<String>,
+    ) -> Self {
         Self {
             http_client: Client::new(),
             base_url,
             sender,
+            authorization_token,
         }
     }
 
@@ -24,6 +31,69 @@ impl EmailClient {
         html_content: &str,
         text_content: &str,
     ) -> Result<(), String> {
-        todo!()
+        // TODO: use `reqwest::Url::join` and change `base_url`'s type from `String` to `reqwest::Url`
+        let url = format!("{}/email", self.base_url);
+        let request_body = SendEmailRequest {
+            from: self.sender.as_ref().to_owned(),
+            to: recipient.as_ref().to_owned(),
+            subject: subject.to_owned(),
+            html_body: html_content.to_owned(),
+            text_body: text_content.to_owned(),
+        };
+        let builder = self
+            .http_client
+            .post(&url)
+            .header(
+                "X-Postmark-Server-Token",
+                self.authorization_token.expose_secret(),
+            )
+            .json(&request_body);
+        Ok(())
+    }
+}
+#[derive(serde::Serialize)]
+struct SendEmailRequest {
+    from: String,
+    to: String,
+    subject: String,
+    html_body: String,
+    text_body: String,
+}
+
+#[cfg(test)]
+mod tests {
+
+    use crate::domain::SubscriberEmail;
+    use crate::email_client::EmailClient;
+    use fake::faker::internet::en::SafeEmail;
+    use fake::faker::lorem::en::{Paragraph, Sentence};
+    use fake::{Fake, Faker};
+    use secrecy::Secret;
+    use wiremock::matchers::any;
+    use wiremock::{Mock, MockServer, ResponseTemplate};
+
+    #[tokio::test]
+    async fn send_email_fires_a_request_to_base_url() {
+        // Arrange
+        let mock_server = MockServer::start().await;
+        let sender = SubscriberEmail::parse(SafeEmail().fake()).unwrap();
+        let email_client = EmailClient::new(mock_server.uri(), sender, Secret::new(Faker.fake()));
+
+        Mock::given(any())
+            .respond_with(ResponseTemplate::new(200))
+            .expect(1)
+            .mount(&mock_server)
+            .await;
+
+        let subscriber_email = SubscriberEmail::parse(SafeEmail().fake()).unwrap();
+        let subject: String = Sentence(1..2).fake();
+        let content: String = Paragraph(1..10).fake();
+
+        // Act
+        let _ = email_client
+            .send_email(subscriber_email, &subject, &content, &content)
+            .await;
+
+        // Assert
     }
 }

src/main.rs

@@ -25,7 +25,11 @@ async fn main() {
         .email_client
         .sender()
         .expect("Invalid sender email address.");
-    let email_client = EmailClient::new(configuration.email_client.base_url, sender_email);
+    let email_client = EmailClient::new(
+        configuration.email_client.base_url,
+        sender_email,
+        configuration.email_client.authorization_token,
+    );
     startup::run(listener, connection_pool, email_client)
         .await
         .unwrap();

tests/health_check.rs

@@ -153,7 +153,11 @@ async fn spawn_app() -> TestApp {
         .email_client
         .sender()
         .expect("Invalid sender email address.");
-    let email_client = EmailClient::new(configuration.email_client.base_url, sender_email);
+    let email_client = EmailClient::new(
+        configuration.email_client.base_url,
+        sender_email,
+        configuration.email_client.authorization_token,
+    );
 
     let service = learn_axum::startup::app(connection_pool.clone(), email_client);
     tokio::spawn(async move {