Database connection and user registration

.github/workflows/general.yml

@@ -0,0 +1,170 @@
+# The name of your workflow. GitHub displays the names of your workflows on your repository's "Actions" tab
+name: Rust
+
+# To automatically trigger the workflow
+on:
+  # NB: this differs from the book's project!
+  # These settings allow us to run this specific CI pipeline for PRs against
+  # this specific branch (a.k.a. book chapter).
+  push:
+    branches:
+      - main
+  pull_request:
+    types: [opened, synchronize, reopened]
+    branches:
+      - main
+
+env:
+  CARGO_TERM_COLOR: always
+  SQLX_VERSION: 0.8.6
+  SQLX_FEATURES: "rustls,postgres"
+  APP_USER: app
+  APP_USER_PWD: secret
+  APP_DB_NAME: newsletter
+
+# A workflow run is made up of one or more jobs, which run in parallel by default
+# Each job runs in a runner environment specified by runs-on
+jobs:
+  # Unique identifier of our job (`job_id`)
+  test:
+    # Sets the name `Test` for the job, which is displayed in the GitHub UI
+    name: Test
+    # Containers must run in Linux based operating systems
+    runs-on: ubuntu-latest
+    # Service containers to run alongside the `test` container job
+    services:
+      # Label used to access the service container
+      postgres:
+        # Docker Hub image
+        image: postgres:14
+        # Environment variables scoped only for the `postgres` element
+        env:
+          POSTGRES_USER: postgres
+          POSTGRES_PASSWORD: password
+          POSTGRES_DB: postgres
+        # When you map ports using the ports keyword, GitHub uses the --publish command to publish the container’s ports to the Docker host
+        # Opens tcp port 5432 on the host and service container
+        ports:
+          - 5432:5432
+    steps:
+      # Downloads a copy of the code in your repository before running CI tests
+      - name: Check out repository code
+        # The uses keyword specifies that this step will run v4 of the actions/checkout action.
+        # 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 }}
+          --features ${{ env.SQLX_FEATURES }}
+          --no-default-features
+          --locked
+      - name: Create app user in Postgres
+        run: |
+          sudo apt-get install postgresql-client
+
+          # Create the application user
+          CREATE_QUERY="CREATE USER ${APP_USER} WITH PASSWORD '${APP_USER_PWD}';"
+          PGPASSWORD="password" psql -U "postgres" -h "localhost" -c "${CREATE_QUERY}"
+
+          # 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
+
+  # `fmt` container job
+  fmt:
+    name: Rustfmt
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Install the Rust toolchain
+        uses: actions-rust-lang/setup-rust-toolchain@v1
+        with:
+          components: rustfmt
+      - name: Enforce formatting
+        run: cargo fmt --check
+
+  # `clippy` container job
+  clippy:
+    name: Clippy
+    runs-on: ubuntu-latest
+    env:
+      # This environment variable forces sqlx to use its offline mode,
+      # which means that it will not attempt to connect to a database
+      # when running the tests. It'll instead use the cached query results.
+      # We check that the cached query results are up-to-date in another job,
+      # to speed up the overall CI pipeline.
+      # This will all be covered in detail in chapter 5.
+      SQLX_OFFLINE: true
+    steps:
+      - uses: actions/checkout@v4
+      - name: Install the Rust toolchain
+        uses: actions-rust-lang/setup-rust-toolchain@v1
+        with:
+          components: clippy
+      - name: Linting
+        run: cargo clippy -- -D warnings
+
+  # `coverage` container job
+  coverage:
+    name: Code coverage
+    runs-on: ubuntu-latest
+    services:
+      postgres:
+        image: postgres:14
+        env:
+          POSTGRES_USER: postgres
+          POSTGRES_PASSWORD: password
+          POSTGRES_DB: postgres
+        ports:
+          - 5432:5432
+    steps:
+      - uses: actions/checkout@v4
+      - name: Install the Rust toolchain
+        uses: actions-rust-lang/setup-rust-toolchain@v1
+        with:
+          components: llvm-tools-preview
+      - name: Install sqlx-cli
+        run: cargo install sqlx-cli
+          --version=${{ env.SQLX_VERSION }}
+          --features ${{ env.SQLX_FEATURES }}
+          --no-default-features
+          --locked
+      - name: Create app user in Postgres
+        run: |
+          sudo apt-get install postgresql-client
+
+          # Create the application user
+          CREATE_QUERY="CREATE USER ${APP_USER} WITH PASSWORD '${APP_USER_PWD}';"
+          PGPASSWORD="password" psql -U "postgres" -h "localhost" -c "${CREATE_QUERY}"
+
+          # 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: Install cargo-llvm-cov
+        uses: taiki-e/install-action@cargo-llvm-cov
+      - name: Generate code coverage
+        run: cargo llvm-cov --all-features --workspace --lcov --output-path lcov.info
+      - name: Generate report
+        run: cargo llvm-cov report --html --output-dir coverage
+      - uses: actions/upload-artifact@v4
+        with:
+          name: "Coverage report"
+          path: coverage/

Cargo.toml

@@ -3,6 +3,24 @@ name = "zero2prod"
 version = "0.1.0"
 edition = "2024"
 
+[lib]
+path = "src/lib.rs"
+
+[[bin]]
+path = "src/main.rs"
+name = "zero2prod"
+
 [dependencies]
 axum = "0.8.4"
-tokio = { version = "1.47.1", features = ["rt-multi-thread"] }
+chrono = { version = "0.4.41", default-features = false, features = ["clock"] }
+config = "0.15.14"
+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-subscriber = { version = "0.3.19", features = ["env-filter"] }
+uuid = { version = "1.18.0", features = ["v4"] }
+
+[dev-dependencies]
+reqwest = "0.12.23"

README.md

@@ -0,0 +1,10 @@
+# zero2prod
+
+## Commands
+
+```
+sudo apt install postgresql-client
+sudo apt install pkg-config
+sudo apt install libssl-dev
+cargo install sqlx-cli --no-default-features --features rustls,postgres
+```

configuration.yaml

@@ -0,0 +1,7 @@
+application_port: 8000
+database:
+  host: "127.0.0.1"
+  port: 5432
+  username: "postgres"
+  password: "password"
+  database_name: "newsletter"

migrations/20250821091459_create_subscriptions_table.sql

@@ -0,0 +1,7 @@
+CREATE TABLE subscriptions (
+    id UUID NOT NULL,
+    email TEXT NOT NULL UNIQUE,
+    name TEXT NOT NULL,
+    subscribed_at TIMESTAMPTZ NOT NULL,
+    PRIMARY KEY (id)
+);

src/configuration.rs

@@ -0,0 +1,42 @@
+use serde::Deserialize;
+
+pub fn get_configuration() -> Result<Settings, config::ConfigError> {
+    let settings = config::Config::builder()
+        .add_source(config::File::new(
+            "configuration.yaml",
+            config::FileFormat::Yaml,
+        ))
+        .build()?;
+    settings.try_deserialize::<Settings>()
+}
+
+#[derive(Deserialize)]
+pub struct Settings {
+    pub database: DatabaseSettings,
+    pub application_port: u16,
+}
+
+#[derive(Deserialize)]
+pub struct DatabaseSettings {
+    pub username: String,
+    pub password: String,
+    pub port: u16,
+    pub host: String,
+    pub database_name: String,
+}
+
+impl DatabaseSettings {
+    pub fn connection_string(&self) -> String {
+        format!(
+            "postgres://{}:{}@{}:{}/{}",
+            self.username, self.password, self.host, self.port, self.database_name
+        )
+    }
+
+    pub fn connection_string_without_db(&self) -> String {
+        format!(
+            "postgres://{}:{}@{}:{}",
+            self.username, self.password, self.host, self.port
+        )
+    }
+}

src/lib.rs

@@ -0,0 +1,3 @@
+pub mod configuration;
+pub mod routes;
+pub mod startup;

src/main.rs

@@ -1,9 +1,31 @@
-use axum::{Router, routing::get};
+use sqlx::PgPool;
+use tokio::net::TcpListener;
+use tracing_subscriber::{layer::SubscriberExt, util::SubscriberInitExt};
+use zero2prod::{configuration::get_configuration, startup::run};
 
 #[tokio::main]
 async fn main() {
-    let app = Router::new().route("/", get(|| async { "Hello, World!" }));
+    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(tracing_subscriber::fmt::layer())
+        .init();
 
-    let listener = tokio::net::TcpListener::bind("0.0.0.0:3000").await.unwrap();
-    axum::serve(listener, app).await.unwrap();
+    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())
+        .await
+        .unwrap();
+
+    run(listener, connection_pool).await
 }

src/routes.rs

@@ -0,0 +1,5 @@
+mod health_check;
+mod subscriptions;
+
+pub use health_check::*;
+pub use subscriptions::*;

src/routes/health_check.rs

@@ -0,0 +1,5 @@
+use axum::{http::StatusCode, response::IntoResponse};
+
+pub async fn health_check() -> impl IntoResponse {
+    StatusCode::OK
+}

src/routes/subscriptions.rs

@@ -0,0 +1,37 @@
+use axum::{Form, extract::State, http::StatusCode, response::IntoResponse};
+use chrono::Utc;
+use serde::Deserialize;
+use sqlx::PgPool;
+use uuid::Uuid;
+
+pub async fn subscribe(
+    State(connection): State<PgPool>,
+    form: Form<FormData>,
+) -> impl IntoResponse {
+    match sqlx::query!(
+        r#"
+            insert into subscriptions (id, email, name, subscribed_at)
+            values ($1, $2, $3, $4);
+    "#,
+        Uuid::new_v4(),
+        form.email,
+        form.name,
+        Utc::now()
+    )
+    .execute(&connection)
+    .await
+    {
+        Ok(_) => StatusCode::OK,
+        Err(e) => {
+            eprintln!("Failed to execute query: {}", e);
+            StatusCode::INTERNAL_SERVER_ERROR
+        }
+    }
+}
+
+#[derive(Deserialize)]
+#[allow(dead_code)]
+pub struct FormData {
+    name: String,
+    email: String,
+}

src/startup.rs

@@ -0,0 +1,36 @@
+use crate::routes::*;
+use axum::{
+    Router,
+    extract::MatchedPath,
+    http::Request,
+    routing::{get, post},
+};
+use sqlx::PgPool;
+use tokio::net::TcpListener;
+use tower_http::trace::TraceLayer;
+
+pub async fn run(listener: TcpListener, connection_pool: PgPool) {
+    axum::serve(listener, app(connection_pool)).await.unwrap();
+}
+
+pub fn app(connection_pool: PgPool) -> Router {
+    Router::new()
+        .route("/health_check", get(health_check))
+        .route("/subscriptions", post(subscribe))
+        .layer(
+            TraceLayer::new_for_http().make_span_with(|request: &Request<_>| {
+                let matched_path = request
+                    .extensions()
+                    .get::<MatchedPath>()
+                    .map(MatchedPath::as_str);
+
+                tracing::info_span!(
+                    "http_request",
+                    method = ?request.method(),
+                    matched_path,
+                    some_other_field = tracing::field::Empty,
+                )
+            }),
+        )
+        .with_state(connection_pool)
+}

tests/health_check.rs

@@ -0,0 +1,122 @@
+use sqlx::{Connection, Executor, PgConnection, PgPool};
+use tokio::net::TcpListener;
+use uuid::Uuid;
+use zero2prod::configuration::{DatabaseSettings, get_configuration};
+
+pub struct TestApp {
+    pub address: String,
+    pub connection_pool: PgPool,
+}
+
+#[tokio::test]
+async fn health_check_works() {
+    let app = spawn_app().await;
+    let client = reqwest::Client::new();
+
+    let response = client
+        .get(format!("http://{}/health_check", app.address))
+        .send()
+        .await
+        .unwrap();
+
+    assert!(response.status().is_success());
+    assert_eq!(Some(0), response.content_length());
+}
+
+#[tokio::test]
+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)
+        .await
+        .expect("Failed to connect to Postgres");
+    let client = reqwest::Client::new();
+
+    let body = "name=alphonse&email=alphonse.paix%40outlook.com";
+    let response = client
+        .post(format!("http://{}/subscriptions", app.address))
+        .header("Content-Type", "application/x-www-form-urlencoded")
+        .body(body)
+        .send()
+        .await
+        .unwrap();
+
+    assert_eq!(200, response.status().as_u16());
+
+    let saved = sqlx::query!("SELECT email, name FROM subscriptions")
+        .fetch_one(&mut connection)
+        .await
+        .expect("Failed to fetch saved subscription");
+
+    assert_eq!(saved.email, "alphonse.paix@outlook.com");
+    assert_eq!(saved.name, "alphonse");
+}
+
+#[tokio::test]
+async fn subscribe_returns_a_422_when_data_is_missing() {
+    let app = spawn_app().await;
+    let client = reqwest::Client::new();
+
+    let test_cases = [
+        ("name=Alphonse", "missing the email"),
+        ("email=alphonse.paix%40outlook.com", "missing the name"),
+        ("", "missing both name and email"),
+    ];
+    for (invalid_body, error_message) in test_cases {
+        let response = client
+            .post(format!("http://{}/subscriptions", app.address))
+            .header("Content-Type", "application/x-www-form-urlencoded")
+            .body(invalid_body)
+            .send()
+            .await
+            .unwrap();
+
+        assert_eq!(
+            422,
+            response.status().as_u16(),
+            "the API did not fail with 422 Unprocessable Entity when the payload was {}.",
+            error_message
+        );
+    }
+}
+
+async fn spawn_app() -> TestApp {
+    let listener = TcpListener::bind("127.0.0.1:0").await.unwrap();
+    let address = listener.local_addr().unwrap().to_string();
+
+    let mut configuration = get_configuration().expect("Failed to read configuration");
+    configuration.database.database_name = Uuid::new_v4().to_string();
+    let connection_pool = configure_database(&configuration.database).await;
+
+    let app = TestApp {
+        address,
+        connection_pool: connection_pool.clone(),
+    };
+
+    tokio::spawn(async move {
+        zero2prod::startup::run(listener, connection_pool).await;
+    });
+
+    app
+}
+
+async fn configure_database(config: &DatabaseSettings) -> PgPool {
+    let connection = PgPool::connect(&config.connection_string_without_db())
+        .await
+        .expect("Failed to connect to Postgres");
+    connection
+        .execute(format!(r#"CREATE DATABASE "{}";"#, config.database_name).as_ref())
+        .await
+        .expect("Failed to create the database");
+
+    let connection_pool = PgPool::connect(&config.connection_string())
+        .await
+        .expect("Failed to connect to Postgres");
+    sqlx::migrate!("./migrations")
+        .run(&connection_pool)
+        .await
+        .expect("Failed to migrate the database");
+
+    connection_pool
+}