feat(config): App can take environ variables

- Change log level of SQLx to TRACE

src/configuration.rs

@@ -1,4 +1,7 @@
 use secrecy::{ExposeSecret, Secret};
+use serde_aux::field_attributes::deserialize_number_from_string;
+use sqlx::postgres::{PgConnectOptions, PgSslMode};
+use sqlx::ConnectOptions;
 
 #[derive(serde::Deserialize)]
 pub struct Settings {
@@ -8,6 +11,7 @@ pub struct Settings {
 
 #[derive(serde::Deserialize)]
 pub struct ApplicationSettings {
+    #[serde(deserialize_with = "deserialize_number_from_string")]
     pub port: u16,
     pub host: String,
 }
@@ -16,9 +20,11 @@ pub struct ApplicationSettings {
 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,
 }
 
 pub fn get_configuration() -> Result<Settings, config::ConfigError> {
@@ -39,6 +45,15 @@ pub fn get_configuration() -> Result<Settings, config::ConfigError> {
         .add_source(config::File::from(
             configuration_directory.join(environment_filename),
         ))
+        // take settings from environment variables
+        // with a prefix of APP and __ as separator
+        //
+        // E.g `APP_APPLICATION_PORT=5001` would set Settings.application.port
+        .add_source(
+            config::Environment::with_prefix("APP")
+                .prefix_separator("_")
+                .separator("__"),
+        )
         .build()?;
 
     settings.try_deserialize::<Settings>()
@@ -73,24 +88,26 @@ Use either `local` or `production`.",
 }
 
 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
-        ))
+    // for normal usage
+    pub fn with_db(&self) -> PgConnectOptions {
+        let mut options = self.without_db().database(&self.database_name);
+        options = options.log_statements(tracing_log::log::LevelFilter::Trace);
+        options
     }
 
-    pub fn connection_string_without_db(&self) -> Secret<String> {
-        Secret::new(format!(
-            "postgres://{}:{}@{}:{}",
-            self.username,
-            self.password.expose_secret(),
-            self.host,
-            self.port
-        ))
+    // for testings, we will set the database name with arbitrary values
+    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

@@ -2,8 +2,7 @@ use std::net::TcpListener;
 
 use email_newsletter_api::telemetry::{get_subscriber, init_subscriber};
 use email_newsletter_api::{configuration::get_configuration, startup};
-use secrecy::ExposeSecret;
-use sqlx::PgPool;
+use sqlx::postgres::PgPoolOptions;
 
 #[tokio::main]
 async fn main() -> Result<(), std::io::Error> {
@@ -16,8 +15,7 @@ async fn main() -> Result<(), std::io::Error> {
     );
     init_subscriber(subscriber);
 
-    let db_conn = PgPool::connect_lazy(configuration.database.connection_string().expose_secret())
-        .expect("Failed to connect to PostgreSQL");
+    let db_conn = PgPoolOptions::new().connect_lazy_with(configuration.database.with_db());
 
     let listener = TcpListener::bind(format!(
         "{}:{}",