Environment variables at runtime to connect to database

src/configuration.rs

@@ -1,5 +1,7 @@
 use secrecy::{ExposeSecret, SecretString};
 use serde::Deserialize;
+use serde_aux::field_attributes::deserialize_number_from_string;
+use sqlx::postgres::{PgConnectOptions, PgSslMode};
 
 pub fn get_configuration() -> Result<Settings, config::ConfigError> {
     let base_path = std::env::current_dir().expect("Failed to determine the current directory");
@@ -13,6 +15,11 @@ pub fn get_configuration() -> Result<Settings, config::ConfigError> {
     let settings = config::Config::builder()
         .add_source(config::File::from(config_dir.join("base.yaml")))
         .add_source(config::File::from(config_dir.join(environment_filename)))
+        .add_source(
+            config::Environment::with_prefix("APP")
+                .prefix_separator("_")
+                .prefix("__"),
+        )
         .build()?;
 
     settings.try_deserialize::<Settings>()
@@ -55,6 +62,7 @@ pub struct Settings {
 
 #[derive(Deserialize)]
 pub struct ApplicationSettings {
+    #[serde(deserialize_with = "deserialize_number_from_string")]
     pub port: u16,
     pub host: String,
 }
@@ -63,32 +71,29 @@ pub struct ApplicationSettings {
 pub struct DatabaseSettings {
     pub username: String,
     pub password: SecretString,
+    #[serde(deserialize_with = "deserialize_number_from_string")]
     pub port: u16,
     pub host: String,
     pub database_name: String,
+    pub require_ssl: bool,
 }
 
 impl DatabaseSettings {
-    pub fn connection_string(&self) -> SecretString {
-        format!(
-            "postgres://{}:{}@{}:{}/{}",
-            self.username,
-            self.password.expose_secret(),
-            self.host,
-            self.port,
-            self.database_name
-        )
-        .into()
+    pub fn with_db(&self) -> PgConnectOptions {
+        self.without_db().database(&self.database_name)
     }
 
-    pub fn connection_string_without_db(&self) -> SecretString {
-        format!(
-            "postgres://{}:{}@{}:{}",
-            self.username,
-            self.password.expose_secret(),
-            self.host,
-            self.port
-        )
-        .into()
+    pub fn without_db(&self) -> PgConnectOptions {
+        let ssl_mode = if self.require_ssl {
+            PgSslMode::Require
+        } else {
+            PgSslMode::Prefer
+        };
+        PgConnectOptions::new()
+            .host(&self.host)
+            .username(&self.username)
+            .password(self.password.expose_secret())
+            .port(self.port)
+            .ssl_mode(ssl_mode)
     }
 }

src/main.rs

@@ -1,5 +1,4 @@
-use secrecy::ExposeSecret;
-use sqlx::PgPool;
+use sqlx::postgres::PgPoolOptions;
 use tokio::net::TcpListener;
 use zero2prod::{configuration::get_configuration, startup::run, telemetry::init_subscriber};
 
@@ -14,8 +13,7 @@ async fn main() {
     .await
     .unwrap();
     tracing::debug!("listening on {}", listener.local_addr().unwrap());
-    let connection_pool =
-        PgPool::connect_lazy(configuration.database.connection_string().expose_secret()).unwrap();
+    let connection_pool = PgPoolOptions::new().connect_lazy_with(configuration.database.with_db());
 
     run(listener, connection_pool).await
 }