add subscriber data validation

Cargo.toml

@@ -25,6 +25,8 @@ tracing-actix-web = "0.7"
 tracing-subscriber = { version = "0.3", features = ["registry", "env-filter"] }
 tracing-bunyan-formatter = "0.3"
 serde-aux = "4.5.0"
+unicode-segmentation = "1.11.0"
+validator = "0.16.0"
 
 [dependencies.sqlx]
 version = "0.7"
@@ -41,3 +43,8 @@ features = [
 [dev-dependencies]
 reqwest = "0.12.2"
 once_cell = "1"
+claims = "0.7"
+fake = "2.9.2"
+quickcheck = "1.0.3"
+quickcheck_macros = "1.0.0"
+rand = "0.8.5"

justfile

@@ -49,6 +49,7 @@ testv:
 
 ## Run the linter
 lint:
+    cargo check
     cargo clippy
 
 ## Authenticate against DigitalOcean

spec.yaml

@@ -27,9 +27,6 @@ services:
     routes:
       - path: /
     envs:
-      - key: APP_APPLICATION__BASE_URL
-        scope: RUN_TIME
-        value: ${APP_URL}
       - key: APP_DATABASE__USERNAME
         scope: RUN_TIME
         value: ${newsletter.USERNAME}

src/domain/mod.rs

@@ -0,0 +1,7 @@
+mod subscriber_email;
+mod subscriber_name;
+mod new_subscriber;
+
+pub use subscriber_email::SubscriberEmail;
+pub use subscriber_name::SubscriberName;
+pub use new_subscriber::NewSubscriber;

src/domain/new_subscriber.rs

@@ -0,0 +1,8 @@
+
+use crate::domain::subscriber_name::SubscriberName;
+use crate::domain::subscriber_email::SubscriberEmail;
+
+pub struct NewSubscriber {
+    pub email: SubscriberEmail,
+    pub name: SubscriberName,
+}

src/domain/subscriber_email.rs

@@ -0,0 +1,64 @@
+use validator::validate_email;
+
+#[derive(Debug)]
+pub struct SubscriberEmail(String);
+
+impl SubscriberEmail {
+    pub fn parse(s: String) -> Result<SubscriberEmail, String> {
+        if validate_email(&s) {
+            Ok(Self(s))
+        }
+        else {
+            Err(format!("{} is not a valid email address.", s))
+        }
+    }
+}
+
+impl AsRef<str> for SubscriberEmail {
+    fn as_ref(&self) -> &str {
+        &self.0
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use fake::faker::internet::en::SafeEmail;
+    use fake::Fake;
+    use rand::{rngs::StdRng, SeedableRng};
+    use claims::assert_err;
+    use crate::domain::SubscriberEmail;
+
+    #[test]
+    fn empty_string_is_rejected() {
+        let email = "".to_string();
+        assert_err!(SubscriberEmail::parse(email));
+    }
+
+    #[test]
+    fn email_missing_at_symbol_is_rejected() {
+        let email = "name.example.com".to_string();
+        assert_err!(SubscriberEmail::parse(email));
+    }
+
+    #[test]
+    fn email_missing_subject_is_rejected() {
+        let email = "@example.com".to_string();
+        assert_err!(SubscriberEmail::parse(email));
+    }
+
+    #[derive(Debug, Clone)]
+    struct ValidEmailFixture(pub String);
+
+    impl quickcheck::Arbitrary for ValidEmailFixture {
+        fn arbitrary(g: &mut quickcheck::Gen) -> Self {
+            let mut rng = StdRng::seed_from_u64(u64::arbitrary(g));
+            let email = SafeEmail().fake_with_rng(&mut rng);
+            Self(email)
+        }
+    }
+
+    #[quickcheck_macros::quickcheck]
+    fn valid_emails_are_parsed_successfully(valid_email: ValidEmailFixture) -> bool {
+        SubscriberEmail::parse(valid_email.0).is_ok()
+    }
+}

src/domain/subscriber_name.rs

@@ -0,0 +1,70 @@
+use unicode_segmentation::UnicodeSegmentation;
+
+#[derive(Debug)]
+pub struct SubscriberName(String);
+
+impl SubscriberName {
+    pub fn parse(s: String) -> Result<SubscriberName, String> {
+        let is_empty_or_whitespace = s.trim().is_empty();
+        let is_too_long = s.graphemes(true).count() > 256;
+        let forbidden_characters = ['/', '(', ')', '"', '<', '>', '\\', '{', '}'];
+        let contains_forbidden_characters = s.chars().any(|c| forbidden_characters.contains(&c));
+        if is_empty_or_whitespace || is_too_long || contains_forbidden_characters {
+            Err(format!("{} is not a valid subscriber name.", s))
+        }
+        else {
+            Ok(Self(s))
+        }
+    }
+}
+
+impl AsRef<str> for SubscriberName {
+    fn as_ref(&self) -> &str {
+        &self.0
+    }
+}
+
+
+#[cfg(test)]
+mod tests {
+    use crate::domain::SubscriberName;
+    use claims::{assert_err, assert_ok};
+
+    #[test]
+    fn a_256_grapheme_long_name_is_valid() {
+        let name = "a".repeat(256);
+        assert_ok!(SubscriberName::parse(name));
+    }
+
+    #[test]
+    fn a_257_grapheme_long_name_is_rejected() {
+        let name = "a".repeat(257);
+        assert_err!(SubscriberName::parse(name));
+    }
+
+    #[test]
+    fn a_whitespaces_only_name_is_rejected() {
+        let name = " ".repeat(10);
+        assert_err!(SubscriberName::parse(name));
+    }
+
+    #[test]
+    fn a_name_with_forbidden_characters_is_rejected() {
+        let name = "a/b".to_string();
+        assert_err!(SubscriberName::parse(name));
+    }
+
+    #[test]
+    fn an_empty_name_is_rejected() {
+        let name = "".to_string();
+        assert_err!(SubscriberName::parse(name));
+    }
+
+    #[test]
+    fn names_containing_an_invalid_character_are_rejected() {
+        for name in &['/', '(', ')', '"', '<', '>', '\\', '{', '}'] {
+            let name = format!("a{}b", name);
+            assert_err!(SubscriberName::parse(name));
+        }
+    }
+}

src/lib.rs

@@ -1,4 +1,5 @@
 pub mod configuration;
+pub mod domain;
 pub mod routes;
 pub mod startup;
 pub mod telemetry;