Validation for user's name and email

Email validation is still primitive but checks if the email could theoretically exist (name@domain.com). Separation of Subscriber type into a module as well as actions that cane be performed on it. Updates to the subscribe functionality to align with new test cases that have been made.

Cargo.lock

@@ -50,7 +50,7 @@ dependencies = [
  "mime",
  "percent-encoding",
  "pin-project-lite",
- "rand",
+ "rand 0.8.4",
  "sha-1 0.10.0",
  "smallvec",
  "zstd",
@@ -194,7 +194,7 @@ version = "0.7.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "fcb51a0695d8f838b1ee009b3fbf66bda078cd64590202a864a8f3e8c4315c47"
 dependencies = [
- "getrandom",
+ "getrandom 0.2.3",
  "once_cell",
  "version_check",
 ]
@@ -349,6 +349,15 @@ dependencies = [
  "winapi",
 ]
 
+[[package]]
+name = "claim"
+version = "0.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f81099d6bb72e1df6d50bb2347224b666a670912bb7f06dbe867a4a070ab3ce8"
+dependencies = [
+ "autocfg",
+]
+
 [[package]]
 name = "config"
 version = "0.11.0"
@@ -565,6 +574,25 @@ dependencies = [
  "cfg-if",
 ]
 
+[[package]]
+name = "env_logger"
+version = "0.7.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "44533bbbb3bb3c1fa17d9f2e4e38bbbaf8396ba82193c4cb1b6445d711445d36"
+dependencies = [
+ "log",
+ "regex",
+]
+
+[[package]]
+name = "fake"
+version = "2.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6479fa2c7e83ddf8be7d435421e093b072ca891b99a49bc84eba098f4044f818"
+dependencies = [
+ "rand 0.7.3",
+]
+
 [[package]]
 name = "firestorm"
 version = "0.4.6"
@@ -687,6 +715,17 @@ dependencies = [
  "winapi",
 ]
 
+[[package]]
+name = "getrandom"
+version = "0.1.16"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8fc3cb4d91f53b50155bdcfd23f6a4c39ae1969c2ae85982b135750cccaf5fce"
+dependencies = [
+ "cfg-if",
+ "libc",
+ "wasi 0.9.0+wasi-snapshot-preview1",
+]
+
 [[package]]
 name = "getrandom"
 version = "0.2.3"
@@ -695,7 +734,7 @@ checksum = "7fcd999463524c52659517fe2cea98493cfe485d10565e7b0fb07dbba7ad2753"
 dependencies = [
  "cfg-if",
  "libc",
- "wasi",
+ "wasi 0.10.2+wasi-snapshot-preview1",
 ]
 
 [[package]]
@@ -994,8 +1033,12 @@ version = "0.1.0"
 dependencies = [
  "actix-web",
  "chrono",
+ "claim",
  "config",
+ "fake",
  "once_cell",
+ "quickcheck",
+ "quickcheck_macros",
  "reqwest",
  "secrecy",
  "serde",
@@ -1007,7 +1050,9 @@ dependencies = [
  "tracing-bunyan-formatter",
  "tracing-log",
  "tracing-subscriber",
+ "unicode-segmentation",
  "uuid",
+ "validator",
 ]
 
 [[package]]
@@ -1327,6 +1372,29 @@ dependencies = [
  "unicode-xid",
 ]
 
+[[package]]
+name = "quickcheck"
+version = "0.9.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a44883e74aa97ad63db83c4bf8ca490f02b2fc02f92575e720c8551e843c945f"
+dependencies = [
+ "env_logger",
+ "log",
+ "rand 0.7.3",
+ "rand_core 0.5.1",
+]
+
+[[package]]
+name = "quickcheck_macros"
+version = "0.9.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "608c156fd8e97febc07dc9c2e2c80bf74cfc6ef26893eae3daf8bc2bc94a4b7f"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "quote"
 version = "1.0.10"
@@ -1336,6 +1404,19 @@ dependencies = [
  "proc-macro2",
 ]
 
+[[package]]
+name = "rand"
+version = "0.7.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6a6b1679d49b24bbfe0c803429aa1874472f50d9b363131f0e89fc356b544d03"
+dependencies = [
+ "getrandom 0.1.16",
+ "libc",
+ "rand_chacha 0.2.2",
+ "rand_core 0.5.1",
+ "rand_hc 0.2.0",
+]
+
 [[package]]
 name = "rand"
 version = "0.8.4"
@@ -1343,9 +1424,19 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2e7573632e6454cf6b99d7aac4ccca54be06da05aca2ef7423d22d27d4d4bcd8"
 dependencies = [
  "libc",
- "rand_chacha",
+ "rand_chacha 0.3.1",
- "rand_core",
+ "rand_core 0.6.3",
- "rand_hc",
+ "rand_hc 0.3.1",
+]
+
+[[package]]
+name = "rand_chacha"
+version = "0.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f4c8ed856279c9737206bf725bf36935d8666ead7aa69b52be55af369d193402"
+dependencies = [
+ "ppv-lite86",
+ "rand_core 0.5.1",
 ]
 
 [[package]]
@@ -1355,7 +1446,16 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e6c10a63a0fa32252be49d21e7709d4d4baf8d231c2dbce1eaa8141b9b127d88"
 dependencies = [
  "ppv-lite86",
- "rand_core",
+ "rand_core 0.6.3",
+]
+
+[[package]]
+name = "rand_core"
+version = "0.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "90bde5296fc891b0cef12a6d03ddccc162ce7b2aff54160af9338f8d40df6d19"
+dependencies = [
+ "getrandom 0.1.16",
 ]
 
 [[package]]
@@ -1364,7 +1464,16 @@ version = "0.6.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d34f1408f55294453790c48b2f1ebbb1c5b4b7563eb1f418bcfcfdbb06ebb4e7"
 dependencies = [
- "getrandom",
+ "getrandom 0.2.3",
+]
+
+[[package]]
+name = "rand_hc"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ca3129af7b92a17112d59ad498c6f81eaf463253766b90396d39ea7a39d6613c"
+dependencies = [
+ "rand_core 0.5.1",
 ]
 
 [[package]]
@@ -1373,7 +1482,7 @@ version = "0.3.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d51e9f596de227fda2ea6c84607f5558e196eeaf43c986b724ba4fb8fdf497e7"
 dependencies = [
- "rand_core",
+ "rand_core 0.6.3",
 ]
 
 [[package]]
@@ -1391,7 +1500,7 @@ version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "528532f3d801c87aec9def2add9ca802fe569e44a544afe633765267840abe64"
 dependencies = [
- "getrandom",
+ "getrandom 0.2.3",
  "redox_syscall",
 ]
 
@@ -1809,7 +1918,7 @@ dependencies = [
  "once_cell",
  "parking_lot",
  "percent-encoding",
- "rand",
+ "rand 0.8.4",
  "rustls",
  "serde",
  "serde_json",
@@ -1961,7 +2070,7 @@ checksum = "dac1c663cfc93810f88aed9b8941d48cabf856a1b111c29a40439018d870eb22"
 dependencies = [
  "cfg-if",
  "libc",
- "rand",
+ "rand 0.8.4",
  "redox_syscall",
  "remove_dir_all",
  "winapi",
@@ -2328,7 +2437,33 @@ version = "0.8.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bc5cf98d8186244414c848017f0e2676b3fcb46807f6668a97dfe67359a3c4b7"
 dependencies = [
- "getrandom",
+ "getrandom 0.2.3",
+]
+
+[[package]]
+name = "validator"
+version = "0.14.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6d0f08911ab0fee2c5009580f04615fa868898ee57de10692a45da0c3bcc3e5e"
+dependencies = [
+ "idna",
+ "lazy_static",
+ "regex",
+ "serde",
+ "serde_derive",
+ "serde_json",
+ "url",
+ "validator_types",
+]
+
+[[package]]
+name = "validator_types"
+version = "0.14.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ded9d97e1d42327632f5f3bae6403c04886e2de3036261ef42deebd931a6a291"
+dependencies = [
+ "proc-macro2",
+ "syn",
 ]
 
 [[package]]
@@ -2353,6 +2488,12 @@ dependencies = [
  "try-lock",
 ]
 
+[[package]]
+name = "wasi"
+version = "0.9.0+wasi-snapshot-preview1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cccddf32554fecc6acb585f82a32a72e28b48f8c4c1883ddfeeeaa96f7d8e519"
+
 [[package]]
 name = "wasi"
 version = "0.10.2+wasi-snapshot-preview1"

Cargo.toml

@@ -26,7 +26,13 @@ tracing-log = "0.1.1"
 serde-aux = "3"
 tracing-actix-web = "0.5.0-beta.7"
 secrecy = { version = "0.8", features = ["serde"] }
+unicode-segmentation = "1"
+validator = "0.14"
 
 [dev-dependencies]
 reqwest = { version = "0.11", features = ["json"] }
-once_cell = "1.7.2"
+once_cell = "1.7.2"
+claim = "0.5"
+fake = "~2.3"
+quickcheck = "0.9.2"
+quickcheck_macros = "0.9.1"

src/domain/mod.rs

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

src/domain/new_subscriber.rs

@@ -0,0 +1,7 @@
+use crate::domain::SubscriberName;
+use crate::domain::SubscriberEmail;
+
+pub struct NewSubscriber {
+    pub email: SubscriberEmail,
+    pub name: SubscriberName,
+}

src/domain/subscriber_email.rs

@@ -0,0 +1,61 @@
+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 super::SubscriberEmail;
+    use claim::assert_err;
+    use fake::faker::internet::en::SafeEmail;
+    use fake::Fake;
+
+    #[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 = "ursuladomain.com".to_string();
+        assert_err!(SubscriberEmail::parse(email));
+    }
+
+    #[test]
+    fn email_missing_subject_is_rejected() {
+        let email = "@domain.com".to_string();
+        assert_err!(SubscriberEmail::parse(email));
+    }
+
+    #[derive(Debug, Clone)]
+    struct ValidEmailFixture(pub String);
+
+    impl quickcheck::Arbitrary for ValidEmailFixture {
+        fn arbitrary<G: quickcheck::Gen>(g: &mut G) -> Self {
+            let email = SafeEmail().fake_with_rng(g);
+            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 +1,64 @@
+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(); // Remove trailing whitespaces and check if containsd any characters
+        let is_too_long = s.graphemes(true).count() > 256;
+        let forbidden_characters = ['/', '(', ')', '"', '<', '>', '\\', '{', '}'];
+        let contains_forbidden_characters = s.chars().any(|g| forbidden_characters.contains(&g)); // Iterate to check if name contains any of the forbidden characters
+    
+        // Return `false` if any conditions are violated
+        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 claim::{assert_err, assert_ok};
+
+    #[test]
+    fn a_name_longer_than_256_graphemes_is_rejected() {
+        let name = "a".repeat(257);
+        assert_err!(SubscriberName::parse(name));
+    }
+
+    #[test]
+    fn whitespace_only_names_are_rejected() {
+        let name = " ".to_string();
+        assert_err!(SubscriberName::parse(name));
+    }
+
+    #[test]
+    fn empty_string_is_rejected() {
+        let name = "".to_string();
+        assert_err!(SubscriberName::parse(name));
+    }
+
+    #[test]
+    fn names_containing_invalid_characters_are_rejected() {
+        for name in &['/', '(', ')', '"', '<', '>', '\\', '{', '}'] {
+            let name = name.to_string();
+            assert_err!(SubscriberName::parse(name));
+        }
+    }
+
+    #[test]
+    fn a_valid_name_is_parsed_successfully() {
+        let name = "Ursula Le Guin".to_string();
+        assert_ok!(SubscriberName::parse(name));
+    }
+}

src/lib.rs

@@ -2,4 +2,5 @@
 pub mod configuration;
 pub mod routes;
 pub mod startup;
-pub mod telemetry;
+pub mod telemetry;
+pub mod domain;

src/routes/subscriptions.rs

@@ -2,7 +2,8 @@ use actix_web::{web, HttpResponse};
 use sqlx::PgPool;
 use chrono::Utc;
 use uuid::Uuid;
-// use tracing_futures::Instrument;
+
+use crate::domain::{NewSubscriber, SubscriberName, SubscriberEmail};
 
 #[derive(serde::Deserialize)]
 pub struct FormData {
@@ -10,6 +11,16 @@ pub struct FormData {
     name: String
 }
 
+impl TryFrom<FormData> for NewSubscriber {
+    type Error = String;
+
+    fn try_from(value: FormData) -> Result<Self, Self::Error> {
+        let name = SubscriberName::parse(value.name)?;
+        let email = SubscriberEmail::parse(value.email)?;
+        Ok(Self { email, name })
+    }
+}
+
 #[allow(clippy::async_yields_async)]
 #[tracing::instrument(
     name = "Adding a new subscriber",
@@ -19,9 +30,12 @@ pub struct FormData {
         subscriber_name = %form.name
     )
 )]
-
 pub async fn subscribe(form: web::Form<FormData>, pool: web::Data<PgPool>,) -> HttpResponse {
-    match insert_subscriber(&pool, &form).await {
+    let new_subscriber = match form.0.try_into() {
+        Ok(form) => form,
+        Err(_) => return HttpResponse::BadRequest().finish(),
+    };
+    match insert_subscriber(&pool, &new_subscriber).await {
         Ok(_) => HttpResponse::Ok().finish(),
         Err(_) => HttpResponse::InternalServerError().finish(),
     }
@@ -29,17 +43,17 @@ pub async fn subscribe(form: web::Form<FormData>, pool: web::Data<PgPool>,) -> H
 
 #[tracing::instrument(
     name = "Saving new subscriber details in the database",
-    skip(form, pool)
+    skip(new_subscriber, pool)
 )]
-pub async fn insert_subscriber(pool: &PgPool, form: &FormData) -> Result<(), sqlx::Error> {
+pub async fn insert_subscriber(pool: &PgPool, new_subscriber: &NewSubscriber) -> Result<(), sqlx::Error> {
     sqlx::query!(
         r#"
     INSERT INTO subscriptions (id, email, name, subscribed_at)
     VALUES ($1, $2, $3, $4)
             "#,
         Uuid::new_v4(),
-        form.email,
+        new_subscriber.email.as_ref(),
-        form.name,
+        new_subscriber.name.as_ref(),
         Utc::now()
     )
     .execute(pool)

tests/health_check.rs

@@ -144,4 +144,33 @@ async fn subscribe_returns_400_for_missing_form_data() {
             "The API did not fail with 400 Bad Request when the payload was {}.", error_message
         );
     }
+}
+
+#[tokio::test]
+async fn subscribe_returns_a_400_when_fields_are_present_but_empty() {
+    // Arrange
+    let app = spawn_app().await;
+    let client = reqwest::Client::new();
+    let test_cases = vec![
+        ("name=&email=ursula_le_guin%40gmail.com", "empty name"),
+        ("name=Ursula&email=", "empty email"),
+        ("name=Ursula&email=definitely-not-an-email", "invalid email"),
+    ];
+
+    for (body, description) in test_cases {
+        // Act
+        let response = client
+            .post(&format!("{}/subscriptions", &app.address))
+            .header("Content-Type", "application/x-www-form-urlencoded")
+            .body(body)
+            .send()
+            .await
+            .expect("Failed to execute request.");
+
+        // Assert
+        assert_eq!(400,
+            response.status().as_u16(),
+            "The API did not return a 400 Bad Request when the payload was {}.", description
+        );
+    }
 }