refactor configs into a crate

apps/api/src/configs/server.rs

@@ -0,0 +1,56 @@
+use std::net::IpAddr;
+
+use config::{Config, ConfigError};
+use tracing::warn;
+
+use super::{
+    FromConfig,
+    key::{SERVER_ADDRESS_KEY, SERVER_PORT_KEY},
+};
+
+#[derive(Debug, Clone)]
+pub struct ServerSettings {
+    pub address: IpAddr,
+    pub port: u16,
+}
+
+impl FromConfig for ServerSettings {
+    fn from_config(_config: &Config) -> Result<Self, String> {
+        Ok(ServerSettings {
+            address: _config
+                .get_string(SERVER_ADDRESS_KEY)
+                .unwrap_or_else(|err| {
+                    const DEFAULT_ADDRESS: &str = "0.0.0.0";
+                    match err {
+                        ConfigError::NotFound(_) => {}
+                        _ => {
+                            warn!(
+                                "Failed to read {} from configuration, defaulting to {}. Error: {}",
+                                SERVER_ADDRESS_KEY, DEFAULT_ADDRESS, err
+                            );
+                        }
+                    };
+                    DEFAULT_ADDRESS.to_string()
+                })
+                .parse()
+                .map_err(|e| format!("Invalid {} in configuration: {}", SERVER_ADDRESS_KEY, e))?,
+
+            port: _config.get_int(SERVER_PORT_KEY).unwrap_or_else(|err| {
+                const DEFAULT_PORT: i64 = 8080;
+                warn!(
+                    "{} not set or invalid in configuration, defaulting to {}. Error: {}",
+                    SERVER_PORT_KEY, DEFAULT_PORT, err
+                );
+                DEFAULT_PORT
+            }) as u16,
+        })
+    }
+
+    fn validate(&self) -> Result<(), String> {
+        #[allow(clippy::absurd_extreme_comparisons, unused_comparisons)]
+        if self.port == 0 || self.port > 65535 {
+            return Err("Server port must be between 1 and 65535".into());
+        }
+        Ok(())
+    }
+}