Complete Chapter 5

+ Add in More CI/CD
+ Update Tests and Configurations

.dockerignore

@@ -0,0 +1,6 @@
+.env
+target/
+tests/
+Dockerfile
+scripts/
+migrations/

.gitlab-ci.yml

@@ -1,50 +1,57 @@
-default:
-  before_script:
-    - rustc --version && cargo --version
-  image: "registry.nickbland.dev/nickbland/rust-docker-ci:latest"
-  cache:
-    key:
-      files:
-        - Cargo.lock
-    paths:
-      - .cargo/
-      - target/
-    policy: pull-push
+image: "rust:latest"
+
+services:
+  - postgres:latest
 
 variables:
-  FF_USE_FASTZIP: "true"
-  CACHE_COMPRESSION_LEVEL: "fastest"
+  POSTGRES_DB: newsletter
+  POSTGRES_USER: postgres
+  POSTGRES_PASSWORD: password
+  POSTGRES_HOST: postgres
+  DB_PORT: 5432
+  DATABASE_URL: "postgres://$POSTGRES_USER:$POSTGRES_PASSWORD@$POSTGRES_HOST:$DB_PORT/$POSTGRES_DB"
+  APP_DATABASE__HOST: $POSTGRES_HOST
+
+cache: # Caches build artifacts so we don't build from scratch in both build and test
+  key: ${CI_COMMIT_REF_SLUG}
+  paths:
+    - .cargo/bin
+    - .cargo/registry/index
+    - .cargo/registry/cache
+    - target/debug/deps
+    - target/debug/build
+  policy: pull-push
+
+default:
+  before_script:
+    - export CARGO_HOME="$CI_PROJECT_DIR/.cargo"
+    - export PATH="$CARGO_HOME/bin:$PATH"
+    - rustc --version
+    - cargo --version
+    - if ! [ -x "$(command -v cargo-sqlx)" ]; then cargo install --version='~0.7' sqlx-cli --no-default-features --features rustls,postgres; fi
+    - apt update -yq && apt-get install -yq postgresql-client
+    - SKIP_DOCKER=true ./scripts/init_db.sh
+    # This is to ensure that the database is reachable and give it some time to initialize.
+    - until psql "dbname=$POSTGRES_DB user=$POSTGRES_USER password=$POSTGRES_PASSWORD host=postgres" -c '\l'; do sleep 3; done
 
 stages:
-  - format
+  - build
   - test
 
-format-code:
-  stage: format
+build:
+  stage: build
   script:
-    - cargo fmt -- --check
-
-postgres-service:
-  stage: test
-  services:
-    - postgres:15-alpine
-  variables:
-    POSTGRES_USER: postgres
-    POSTGRES_PASSWORD: password
-    POSTGRES_DB: newsletter
-    POSTGRES_HOST: postgres
-    POSTGRES_PORT: 5432
-  script:
-    - SKIP_DOCKER=true ./scripts/init_db.sh # Migrate DB
+    - cargo build
 
 test-code:
   stage: test
-  needs: ["postgres-service"]
   script:
-    - export DATABASE_URL="postgres://postgres:password@postgres:5432/newsletter" cargo test
+    - cargo test
+    - if ! [ -x "$(command -v cargo-tarpaulin)" ]; then cargo install cargo-tarpaulin; fi
+    - cargo tarpaulin --ignore-tests
 
 lint-code:
   stage: test
-  needs: ["postgres-service"]
   script:
-    - DATABASE_URL="postgres://postgres:password@postgres:5432/newsletter" cargo clippy -- -D warnings
+    - rustup component add clippy
+    - cargo clippy -- -D warnings

.sqlx/query-bcfcfebc6f5e8ffbf97d97c5a209be78b46d703924482cf8b43842705fcb7714.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": "bcfcfebc6f5e8ffbf97d97c5a209be78b46d703924482cf8b43842705fcb7714"
+}

Cargo.lock

@@ -1164,6 +1164,7 @@ dependencies = [
  "reqwest",
  "secrecy",
  "serde",
+ "serde-aux",
  "sqlx",
  "tokio",
  "tracing",
@@ -1849,6 +1850,17 @@ dependencies = [
  "serde_derive",
 ]
 
+[[package]]
+name = "serde-aux"
+version = "4.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0d2e8bfba469d06512e11e3311d4d051a4a387a5b42d010404fecf3200321c95"
+dependencies = [
+ "chrono",
+ "serde",
+ "serde_json",
+]
+
 [[package]]
 name = "serde_derive"
 version = "1.0.188"

Cargo.toml

@@ -14,6 +14,7 @@ name = "mail_app"
 actix-web = "4"
 tokio = { version = "1", features = ["macros", "rt-multi-thread"] }
 serde = { version = "1", features = ["derive"] }
+serde-aux = "4"
 config = { version = "0.13", default-features = false, features = ["yaml"] }
 uuid = { version = "1", features = ["v4"] }
 chrono = { version = "0.4.22", default-features = false, features = ["clock"] }

Dockerfile

@@ -0,0 +1,32 @@
+##### Chef
+FROM lukemathwalker/cargo-chef:latest-rust-1.76.0 as chef
+WORKDIR /app
+RUN apt update && apt install lld clang -y
+
+##### Planner
+FROM chef as planner
+COPY . .
+RUN cargo chef prepare --recipe-path recipe.json
+
+##### Builder
+# Builder prepares project dependancies, not the application.
+FROM chef as builder
+COPY --from=planner /app/recipe.json recipe.json
+RUN cargo chef cook --release --recipe-path recipe.json
+COPY . .
+ENV SQLX_OFFLINE true
+# Now build the application itself.
+RUN cargo build --release --bin mail_app
+
+##### Runtime
+FROM debian:bookworm-slim as runtime
+
+WORKDIR /app
+RUN apt update && apt install -y --no-install-recommends openssl ca-certificates \
+    && apt autoremove -y \
+    && apt clean -y \
+    && rm -rf /var/lib/apt/lists/*
+COPY --from=builder /app/target/release/mail_app mail_app
+COPY configuration  configuration
+ENV APP_ENVIRONMENT production
+ENTRYPOINT ["./mail_app"]

configuration.yaml

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

configuration/base.yaml

@@ -0,0 +1,8 @@
+application:
+  port: 8000
+database:
+  host: "localhost"
+  port: 5432
+  username: "postgres"
+  password: "password"
+  database_name: "newsletter"

configuration/local.yaml

@@ -0,0 +1,4 @@
+application:
+  host: 127.0.0.1
+database:
+  require_ssl: false

configuration/production.yaml

@@ -0,0 +1,4 @@
+application:
+  host: 0.0.0.0
+database:
+  require_ssl: true

scripts/remove_test_dbs.sh

@@ -0,0 +1,14 @@
+#!/usr/bin/env bash
+set -x
+set -eo pipefail
+
+DB_USER="${POSTGRES_USER:=postgres}"
+DB_PASSWORD="${POSTGRES_PASSWORD:=password}"
+DB_NAME="${POSTGRES_DB:=newsletter}"
+DB_PORT="${POSTGRES_PORT:=5432}"
+DB_HOST="${POSTGRES_HOST:=localhost}"
+
+for dbname in $(psql -h "$DB_HOST" -p "$DB_PORT" -U "$DB_USER" -d "$DB_NAME" -c "copy (select datname from pg_database where datname like '%-%-%-%-%') to stdout") ; do
+    echo "dropping database $dbname"
+    dropdb -h "$DB_HOST" -p "$DB_PORT" -U "$DB_USER" "$dbname"
+done

src/configuration.rs

@@ -1,50 +1,105 @@
 use secrecy::{ExposeSecret, Secret};
+use serde_aux::field_attributes::deserialize_number_from_string;
+use sqlx::postgres::{PgConnectOptions, PgSslMode};
 
 #[derive(serde::Deserialize)]
 pub struct Settings {
     pub database: DatabaseSettings,
-    pub application_port: u16,
+    pub application: ApplicationSettings,
 }
 
 #[derive(serde::Deserialize)]
 pub struct DatabaseSettings {
     pub username: String,
     pub password: Secret<String>,
+    #[serde(deserialize_with = "deserialize_number_from_string")]
     pub port: u16,
     pub host: String,
     pub database_name: String,
+    pub require_ssl: bool,
+}
+
+#[derive(serde::Deserialize)]
+pub struct ApplicationSettings {
+    #[serde(deserialize_with = "deserialize_number_from_string")]
+    pub port: u16,
+    pub host: String,
+}
+
+pub enum Environment {
+    Local,
+    Production,
+}
+
+impl Environment {
+    pub fn as_str(&self) -> &'static str {
+        match self {
+            Environment::Local => "local",
+            Environment::Production => "production",
+        }
+    }
+}
+
+impl TryFrom<String> for Environment {
+    type Error = String;
+
+    fn try_from(s: String) -> Result<Self, Self::Error> {
+        match s.to_lowercase().as_str() {
+            "local" => Ok(Environment::Local),
+            "production" => Ok(Environment::Production),
+            e => Err(format!(
+                "{} is not a supported environment. Use `local` or `production`",
+                e
+            )),
+        }
+    }
 }
 
 pub fn get_configuration() -> Result<Settings, config::ConfigError> {
+    let base_path = std::env::current_dir().expect("Failed to determine the current directory");
+    let configuration_directory = base_path.join("configuration");
+
+    // Detect current environment, default to LOCAL
+    let environment: Environment = std::env::var("APP_ENVIRONMENT")
+        .unwrap_or_else(|_| "local".into())
+        .try_into()
+        .expect("Failed to parse APP_ENVIRONMENT");
+    let environment_filename = format!("{}.yaml", environment.as_str());
+
     // initialise config reader
     let settings = config::Config::builder()
-        .add_source(config::File::new(
-            "configuration.yaml",
-            config::FileFormat::Yaml,
+        .add_source(config::File::from(
+            configuration_directory.join("base.yaml"),
         ))
+        .add_source(config::File::from(
+            configuration_directory.join(environment_filename),
+        ))
+        .add_source(
+            config::Environment::with_prefix("APP")
+                .prefix_separator("_")
+                .separator("__"),
+        )
         .build()?;
+
     settings.try_deserialize::<Settings>()
 }
 
 impl DatabaseSettings {
-    pub fn connection_string(&self) -> Secret<String> {
-        Secret::new(format!(
-            "postgres://{}:{}@{}:{}/{}",
-            self.username,
-            self.password.expose_secret(),
-            self.host,
-            self.port,
-            self.database_name
-        ))
+    pub fn without_db(&self) -> PgConnectOptions {
+        let ssl_mode = if self.require_ssl {
+            PgSslMode::Require
+        } else {
+            PgSslMode::Prefer
+        };
+        PgConnectOptions::new()
+            .username(&self.username)
+            .password(self.password.expose_secret())
+            .host(&self.host)
+            .port(self.port)
+            .ssl_mode(ssl_mode)
     }
 
-    pub fn connection_string_without_db(&self) -> Secret<String> {
-        Secret::new(format!(
-            "postgres://{}:{}@{}:{}",
-            self.username,
-            self.password.expose_secret(),
-            self.host,
-            self.port
-        ))
+    pub fn with_db(&self) -> PgConnectOptions {
+        self.without_db().database(&self.database_name)
     }
 }

src/main.rs

@@ -1,8 +1,7 @@
 use mail_app::configuration::get_configuration;
 use mail_app::startup::run;
 use mail_app::telemetry::{get_subscriber, init_subscriber};
-use secrecy::ExposeSecret;
-use sqlx::postgres::PgPool;
+use sqlx::postgres::PgPoolOptions;
 use std::net::TcpListener;
 
 #[tokio::main]
@@ -11,11 +10,11 @@ async fn main() -> Result<(), std::io::Error> {
     init_subscriber(subscriber);
 
     let configuration = get_configuration().expect("Failed to read configuration");
-    let connection_pool =
-        PgPool::connect(&configuration.database.connection_string().expose_secret())
-            .await
-            .expect("Failed to connect to Postgres.");
-    let address = format!("127.0.0.1:{}", configuration.application_port);
+    let connection_pool = PgPoolOptions::new().connect_lazy_with(configuration.database.with_db());
+    let address = format!(
+        "{}:{}",
+        configuration.application.host, configuration.application.port
+    );
     let listener = TcpListener::bind(address)?;
     run(listener, connection_pool)?.await
 }

tests/health_check.rs

@@ -2,8 +2,7 @@ use mail_app::configuration::{get_configuration, DatabaseSettings};
 use mail_app::startup::run;
 use mail_app::telemetry::{get_subscriber, init_subscriber};
 use once_cell::sync::Lazy;
-use secrecy::ExposeSecret;
-use sqlx::{Executor, PgPool};
+use sqlx::{Connection, Executor, PgConnection, PgPool};
 use std::net::TcpListener;
 use uuid::Uuid;
 
@@ -47,7 +46,7 @@ async fn spawn_app() -> TestApp {
 
 pub async fn configure_database(config: &DatabaseSettings) -> PgPool {
     // Create Database
-    let connection = PgPool::connect(&config.connection_string_without_db().expose_secret())
+    let mut connection = PgConnection::connect_with(&config.without_db())
         .await
         .expect("Failed to connect to Postgres.");
     connection
@@ -56,7 +55,7 @@ pub async fn configure_database(config: &DatabaseSettings) -> PgPool {
         .expect("Failed to create database.");
 
     // Migrate Database
-    let connection_pool = PgPool::connect(&config.connection_string().expose_secret())
+    let connection_pool = PgPool::connect_with(config.with_db())
         .await
         .expect("Failed to connect to Postgres.");
     sqlx::migrate!("./migrations")