[Add] Structure

src/db/mod.rs

@@ -0,0 +1,38 @@
+use crate::error::{OmegaError, Result};
+use once_cell::sync::Lazy;
+use sqlx::{MySql, Pool, mysql::MySqlPoolOptions};
+use std::{env, sync::Arc};
+use tokio::sync::RwLock;
+
+pub mod iota_repo;
+pub mod notification_repo;
+pub mod omikron_repo;
+pub mod short_link_repo;
+pub mod user_repo;
+
+pub type DbPool = Pool<MySql>;
+
+static POOL: Lazy<Arc<RwLock<Option<DbPool>>>> = Lazy::new(|| Arc::new(RwLock::new(None)));
+
+pub async fn pool() -> Result<DbPool> {
+    POOL.read()
+        .await
+        .as_ref()
+        .cloned()
+        .ok_or(OmegaError::DatabaseNotInitialized)
+}
+
+pub async fn initialize() -> Result<()> {
+    let url =
+        env::var("DB_URL").map_err(|_| OmegaError::Validation("DB_URL is not set".to_string()))?;
+    let pool = MySqlPoolOptions::new()
+        .max_connections(200)
+        .connect(&url)
+        .await?;
+    sqlx::migrate!()
+        .run(&pool)
+        .await
+        .map_err(|error| OmegaError::Validation(format!("database migration failed: {error}")))?;
+    *POOL.write().await = Some(pool);
+    Ok(())
+}