refactor configs into a crate

apps/api/src/configs/database.rs

@@ -0,0 +1,53 @@
+use config::{Config, ConfigError};
+use tracing::warn;
+
+use super::{
+    FromConfig,
+    key::{DATABASE_MAX_CONNECTIONS_KEY, DATABASE_MIGRATE_ON_STARTUP_KEY},
+};
+
+#[derive(Debug, Clone)]
+pub struct DatabaseSettings {
+    pub url: String,
+    pub max_connections: u32,
+    pub migrate_on_startup: bool,
+}
+
+impl FromConfig for DatabaseSettings {
+    fn from_config(_config: &Config) -> Result<Self, String> {
+        Ok(DatabaseSettings {
+            url: _config
+                .get_string(super::key::DATABASE_URL_KEY)
+                .map_err(|op| match op {
+                    ConfigError::NotFound(_) => "Database URL not found in configuration".into(),
+                    err => {
+                        format!("Failed to read Database URL from configuration {err}")
+                    }
+                })?,
+            max_connections: _config
+                .get_int(DATABASE_MAX_CONNECTIONS_KEY)
+                .unwrap_or_else(|err| {
+                    const DEFAULT_MAX_CONNECTIONS: i64 = 10;
+                    warn!(
+                        "{} not set or invalid in configuration, defaulting to {}. Error: {}",
+                        DATABASE_MAX_CONNECTIONS_KEY, DEFAULT_MAX_CONNECTIONS, err
+                    );
+                    DEFAULT_MAX_CONNECTIONS
+                }) as u32,
+            migrate_on_startup: _config
+                .get_bool(DATABASE_MIGRATE_ON_STARTUP_KEY)
+                .unwrap_or_else(|err| {
+                    const DEFAULT_MIGRATE_ON_STARTUP: bool = true;
+                    warn!(
+                        "{} not set or invalid in configuration, defaulting to {}. Error: {}",
+                        DATABASE_MIGRATE_ON_STARTUP_KEY, DEFAULT_MIGRATE_ON_STARTUP, err
+                    );
+                    DEFAULT_MIGRATE_ON_STARTUP
+                }),
+        })
+    }
+
+    fn validate(&self) -> Result<(), String> {
+        Ok(())
+    }
+}