Telemetry

.github/workflows/general.yml

@@ -53,12 +53,10 @@ jobs:
         # This is an action that checks out your repository onto the runner, allowing you to run scripts or other actions against your code (such as build and test tools).
         # You should use the checkout action any time your workflow will run against the repository's code.
         uses: actions/checkout@v4
-
       # This GitHub Action installs a Rust toolchain using rustup. It is designed for one-line concise usage and good defaults.
       # It also takes care of caching intermediate build artifacts.
       - name: Install the Rust toolchain
         uses: actions-rust-lang/setup-rust-toolchain@v1
-
       - name: Install sqlx-cli
         run: cargo install sqlx-cli
           --version=${{ env.SQLX_VERSION }}
@@ -76,13 +74,10 @@ jobs:
           # Grant create db privileges to the app user
           GRANT_QUERY="ALTER USER ${APP_USER} CREATEDB;"
           PGPASSWORD="password" psql -U "postgres" -h "localhost" -c "${GRANT_QUERY}"
-
       - name: Migrate database
         run: SKIP_DOCKER=true ./scripts/init_db.sh
-
       - name: Run tests
         run: cargo test
-
       - name: Check that queries are fresh
         run: cargo sqlx prepare --workspace --check -- --all-targets
 

.sqlx/query-829555ccf8877b594f4b0691e42315405521c985dfd196902df2ccc74e2aeb49.json

@@ -0,0 +1,17 @@
+{
+  "db_name": "PostgreSQL",
+  "query": "\n        INSERT INTO subscriptions (id, email, name, subscribed_at)\n        VALUES ($1, $2, $3, $4);\n        ",
+  "describe": {
+    "columns": [],
+    "parameters": {
+      "Left": [
+        "Uuid",
+        "Text",
+        "Text",
+        "Timestamptz"
+      ]
+    },
+    "nullable": []
+  },
+  "hash": "829555ccf8877b594f4b0691e42315405521c985dfd196902df2ccc74e2aeb49"
+}

Cargo.lock

@@ -17,6 +17,19 @@ version = "2.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "320119579fcad9c21884f5c4861d16174d0e06250625266f50fe6898340abefa"
 
+[[package]]
+name = "ahash"
+version = "0.8.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5a15f179cd60c4584b8a8c596927aadc462e27f2ca70c04e0071964a73ba7a75"
+dependencies = [
+ "cfg-if",
+ "getrandom 0.3.3",
+ "once_cell",
+ "version_check",
+ "zerocopy",
+]
+
 [[package]]
 name = "aho-corasick"
 version = "1.1.3"
@@ -381,6 +394,15 @@ dependencies = [
  "zeroize",
 ]
 
+[[package]]
+name = "deranged"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9c9e6a11ca8224451684bc0d7d5a7adbf8f2fd6887261a1cfc3c0432f9d4068e"
+dependencies = [
+ "powerfmt",
+]
+
 [[package]]
 name = "digest"
 version = "0.10.7"
@@ -620,6 +642,16 @@ dependencies = [
  "version_check",
 ]
 
+[[package]]
+name = "gethostname"
+version = "0.2.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c1ebd34e35c46e00bb73e81363248d627782724609fe1b6396f553f68fe3862e"
+dependencies = [
+ "libc",
+ "winapi",
+]
+
 [[package]]
 name = "getrandom"
 version = "0.2.16"
@@ -1226,6 +1258,12 @@ dependencies = [
  "zeroize",
 ]
 
+[[package]]
+name = "num-conv"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "51d515d32fb182ee37cda2ccdcb92950d6a3c2893aa280e540671c2cd0f3b1d9"
+
 [[package]]
 name = "num-integer"
 version = "0.1.46"
@@ -1473,6 +1511,12 @@ dependencies = [
  "zerovec",
 ]
 
+[[package]]
+name = "powerfmt"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "439ee305def115ba05938db6eb1644ff94165c5ab5e9420d1c1bcedbba909391"
+
 [[package]]
 name = "ppv-lite86"
 version = "0.2.21"
@@ -1766,6 +1810,16 @@ version = "1.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "94143f37725109f92c262ed2cf5e59bce7498c01bcc1502d7b9afe439a4e9f49"
 
+[[package]]
+name = "secrecy"
+version = "0.10.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e891af845473308773346dc847b2c23ee78fe442e0472ac50e22a18a93d3ae5a"
+dependencies = [
+ "serde",
+ "zeroize",
+]
+
 [[package]]
 name = "security-framework"
 version = "2.11.1"
@@ -2269,6 +2323,37 @@ dependencies = [
  "cfg-if",
 ]
 
+[[package]]
+name = "time"
+version = "0.3.41"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8a7619e19bc266e0f9c5e6686659d394bc57973859340060a69221e57dbc0c40"
+dependencies = [
+ "deranged",
+ "itoa",
+ "num-conv",
+ "powerfmt",
+ "serde",
+ "time-core",
+ "time-macros",
+]
+
+[[package]]
+name = "time-core"
+version = "0.1.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c9e9a38711f559d9e3ce1cdb06dd7c5b8ea546bc90052da6d06bb76da74bb07c"
+
+[[package]]
+name = "time-macros"
+version = "0.2.22"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3526739392ec93fd8b359c8e98514cb3e8e021beb4e5f597b00a0221f8ed8a49"
+dependencies = [
+ "num-conv",
+ "time-core",
+]
+
 [[package]]
 name = "tiny-keccak"
 version = "2.0.2"
@@ -2477,6 +2562,24 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "tracing-bunyan-formatter"
+version = "0.3.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2d637245a0d8774bd48df6482e086c59a8b5348a910c3b0579354045a9d82411"
+dependencies = [
+ "ahash",
+ "gethostname",
+ "log",
+ "serde",
+ "serde_json",
+ "time",
+ "tracing",
+ "tracing-core",
+ "tracing-log 0.1.4",
+ "tracing-subscriber",
+]
+
 [[package]]
 name = "tracing-core"
 version = "0.1.34"
@@ -2487,6 +2590,17 @@ dependencies = [
  "valuable",
 ]
 
+[[package]]
+name = "tracing-log"
+version = "0.1.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f751112709b4e791d8ce53e32c4ed2d353565a795ce84da2285393f41557bdf2"
+dependencies = [
+ "log",
+ "once_cell",
+ "tracing-core",
+]
+
 [[package]]
 name = "tracing-log"
 version = "0.2.0"
@@ -2513,7 +2627,7 @@ dependencies = [
  "thread_local",
  "tracing",
  "tracing-core",
- "tracing-log",
+ "tracing-log 0.2.0",
 ]
 
 [[package]]
@@ -3076,12 +3190,15 @@ dependencies = [
  "axum",
  "chrono",
  "config",
+ "once_cell",
  "reqwest",
+ "secrecy",
  "serde",
  "sqlx",
  "tokio",
  "tower-http",
  "tracing",
+ "tracing-bunyan-formatter",
  "tracing-subscriber",
  "uuid",
 ]

Cargo.toml

@@ -14,13 +14,16 @@ name = "zero2prod"
 axum = "0.8.4"
 chrono = { version = "0.4.41", default-features = false, features = ["clock"] }
 config = "0.15.14"
+secrecy = { version = "0.10.3", features = ["serde"] }
 serde = { version = "1.0.219", features = ["derive"] }
 sqlx = { version = "0.8.6", features = ["runtime-tokio-rustls", "macros", "postgres", "uuid", "chrono", "migrate"] }
 tokio = { version = "1.47.1", features = ["macros", "rt-multi-thread"] }
 tower-http = { version = "0.6.6", features = ["trace"] }
 tracing = "0.1.41"
+tracing-bunyan-formatter = "0.3.10"
 tracing-subscriber = { version = "0.3.19", features = ["env-filter"] }
 uuid = { version = "1.18.0", features = ["v4"] }
 
 [dev-dependencies]
+once_cell = "1.21.3"
 reqwest = "0.12.23"

src/configuration.rs

@@ -1,3 +1,4 @@
+use secrecy::{ExposeSecret, SecretString};
 use serde::Deserialize;
 
 pub fn get_configuration() -> Result<Settings, config::ConfigError> {
@@ -19,24 +20,33 @@ pub struct Settings {
 #[derive(Deserialize)]
 pub struct DatabaseSettings {
     pub username: String,
-    pub password: String,
+    pub password: SecretString,
     pub port: u16,
     pub host: String,
     pub database_name: String,
 }
 
 impl DatabaseSettings {
-    pub fn connection_string(&self) -> String {
+    pub fn connection_string(&self) -> SecretString {
         format!(
             "postgres://{}:{}@{}:{}/{}",
-            self.username, self.password, self.host, self.port, self.database_name
+            self.username,
+            self.password.expose_secret(),
+            self.host,
+            self.port,
+            self.database_name
         )
+        .into()
     }
 
-    pub fn connection_string_without_db(&self) -> String {
+    pub fn connection_string_without_db(&self) -> SecretString {
         format!(
             "postgres://{}:{}@{}:{}",
-            self.username, self.password, self.host, self.port
+            self.username,
+            self.password.expose_secret(),
+            self.host,
+            self.port
         )
+        .into()
     }
 }

src/lib.rs

@@ -1,3 +1,4 @@
 pub mod configuration;
 pub mod routes;
 pub mod startup;
+pub mod telemetry;

src/main.rs

@@ -1,29 +1,18 @@
+use secrecy::ExposeSecret;
 use sqlx::PgPool;
 use tokio::net::TcpListener;
-use tracing_subscriber::{layer::SubscriberExt, util::SubscriberInitExt};
+use zero2prod::{configuration::get_configuration, startup::run, telemetry::init_subscriber};
-use zero2prod::{configuration::get_configuration, startup::run};
 
 #[tokio::main]
 async fn main() {
-    tracing_subscriber::registry()
+    init_subscriber(std::io::stdout);
-        .with(
-            tracing_subscriber::EnvFilter::try_from_default_env().unwrap_or_else(|_| {
-                format!(
-                    "{}=debug,tower_http=debug,axum::rejection=trace",
-                    env!("CARGO_CRATE_NAME")
-                )
-                .into()
-            }),
-        )
-        .with(tracing_subscriber::fmt::layer())
-        .init();
-
     let configuration = get_configuration().expect("Failed to read configuration");
     let listener = TcpListener::bind(format!("127.0.0.1:{}", configuration.application_port))
         .await
         .unwrap();
     tracing::debug!("listening on {}", listener.local_addr().unwrap());
-    let connection_pool = PgPool::connect(&configuration.database.connection_string())
+    let connection_pool =
+        PgPool::connect(configuration.database.connection_string().expose_secret())
             .await
             .unwrap();
 

src/routes/subscriptions.rs

@@ -4,32 +4,53 @@ use serde::Deserialize;
 use sqlx::PgPool;
 use uuid::Uuid;
 
+#[tracing::instrument(
+    name = "Adding a new subscriber",
+    skip(connection, form),
+    fields(
+        subscriber_email = %form.email,
+        subscriber_name = %form.name
+    )
+)]
 pub async fn subscribe(
     State(connection): State<PgPool>,
     form: Form<FormData>,
 ) -> impl IntoResponse {
-    match sqlx::query!(
+    if insert_subscriber(&connection, &form).await.is_err() {
+        StatusCode::INTERNAL_SERVER_ERROR
+    } else {
+        StatusCode::OK
+    }
+}
+
+#[tracing::instrument(
+    name = "Saving new subscriber details in the database",
+    skip(connection, form)
+)]
+pub async fn insert_subscriber(
+    connection: &PgPool,
+    form: &Form<FormData>,
+) -> Result<(), sqlx::Error> {
+    sqlx::query!(
         r#"
-            insert into subscriptions (id, email, name, subscribed_at)
+        INSERT INTO subscriptions (id, email, name, subscribed_at)
-            values ($1, $2, $3, $4);
+        VALUES ($1, $2, $3, $4);
         "#,
         Uuid::new_v4(),
         form.email,
         form.name,
         Utc::now()
     )
-    .execute(&connection)
+    .execute(connection)
     .await
-    {
+    .map_err(|e| {
-        Ok(_) => StatusCode::OK,
+        tracing::error!("Failed to execute query: {:?}", e);
-        Err(e) => {
+        e
-            eprintln!("Failed to execute query: {}", e);
+    })?;
-            StatusCode::INTERNAL_SERVER_ERROR
+    Ok(())
-        }
-    }
 }
 
-#[derive(Deserialize)]
+#[derive(Debug, Deserialize)]
 #[allow(dead_code)]
 pub struct FormData {
     name: String,

src/startup.rs

@@ -8,6 +8,7 @@ use axum::{
 use sqlx::PgPool;
 use tokio::net::TcpListener;
 use tower_http::trace::TraceLayer;
+use uuid::Uuid;
 
 pub async fn run(listener: TcpListener, connection_pool: PgPool) {
     axum::serve(listener, app(connection_pool)).await.unwrap();
@@ -23,11 +24,13 @@ pub fn app(connection_pool: PgPool) -> Router {
                     .extensions()
                     .get::<MatchedPath>()
                     .map(MatchedPath::as_str);
+                let request_id = Uuid::new_v4().to_string();
 
                 tracing::info_span!(
                     "http_request",
                     method = ?request.method(),
                     matched_path,
+                    request_id,
                     some_other_field = tracing::field::Empty,
                 )
             }),

src/telemetry.rs

@@ -0,0 +1,22 @@
+use tracing_bunyan_formatter::{BunyanFormattingLayer, JsonStorageLayer};
+use tracing_subscriber::{fmt::MakeWriter, layer::SubscriberExt, util::SubscriberInitExt};
+
+pub fn init_subscriber<Sink>(sink: Sink)
+where
+    Sink: for<'a> MakeWriter<'a> + Send + Sync + 'static,
+{
+    let formatting_layer = BunyanFormattingLayer::new(env!("CARGO_CRATE_NAME").into(), sink);
+    tracing_subscriber::registry()
+        .with(
+            tracing_subscriber::EnvFilter::try_from_default_env().unwrap_or_else(|_| {
+                format!(
+                    "{}=debug,tower_http=debug,axum::rejection=trace",
+                    env!("CARGO_CRATE_NAME")
+                )
+                .into()
+            }),
+        )
+        .with(JsonStorageLayer)
+        .with(formatting_layer)
+        .init();
+}

tests/health_check.rs

@@ -1,7 +1,20 @@
+use once_cell::sync::Lazy;
+use secrecy::ExposeSecret;
 use sqlx::{Connection, Executor, PgConnection, PgPool};
 use tokio::net::TcpListener;
 use uuid::Uuid;
-use zero2prod::configuration::{DatabaseSettings, get_configuration};
+use zero2prod::{
+    configuration::{DatabaseSettings, get_configuration},
+    telemetry::init_subscriber,
+};
+
+static TRACING: Lazy<()> = Lazy::new(|| {
+    if std::env::var("TEST_LOG").is_ok() {
+        init_subscriber(std::io::stdout);
+    } else {
+        init_subscriber(std::io::sink);
+    }
+});
 
 pub struct TestApp {
     pub address: String,
@@ -28,7 +41,7 @@ async fn subscribe_returns_a_200_for_valid_form_data() {
     let app = spawn_app().await;
     let configuration = get_configuration().expect("Failed to read configuration");
     let connection_string = configuration.database.connection_string();
-    let mut connection = PgConnection::connect(&connection_string)
+    let mut connection = PgConnection::connect(connection_string.expose_secret())
         .await
         .expect("Failed to connect to Postgres");
     let client = reqwest::Client::new();
@@ -82,6 +95,8 @@ async fn subscribe_returns_a_422_when_data_is_missing() {
 }
 
 async fn spawn_app() -> TestApp {
+    Lazy::force(&TRACING);
+
     let listener = TcpListener::bind("127.0.0.1:0").await.unwrap();
     let address = listener.local_addr().unwrap().to_string();
 
@@ -102,7 +117,7 @@ async fn spawn_app() -> TestApp {
 }
 
 async fn configure_database(config: &DatabaseSettings) -> PgPool {
-    let connection = PgPool::connect(&config.connection_string_without_db())
+    let connection = PgPool::connect(config.connection_string_without_db().expose_secret())
         .await
         .expect("Failed to connect to Postgres");
     connection
@@ -110,7 +125,7 @@ async fn configure_database(config: &DatabaseSettings) -> PgPool {
         .await
         .expect("Failed to create the database");
 
-    let connection_pool = PgPool::connect(&config.connection_string())
+    let connection_pool = PgPool::connect(config.connection_string().expose_secret())
         .await
         .expect("Failed to connect to Postgres");
     sqlx::migrate!("./migrations")