Add all connectors

moneymgr_backend/src/connections/db_connection.rs

@@ -0,0 +1,38 @@
+use crate::app_config::AppConfig;
+use diesel::PgConnection;
+use diesel::r2d2::{ConnectionManager, Pool, PooledConnection};
+use diesel_migrations::{EmbeddedMigrations, MigrationHarness, embed_migrations};
+use lazy_static::lazy_static;
+use std::sync::Arc;
+
+const MIGRATIONS: EmbeddedMigrations = embed_migrations!();
+
+pub type DBConn = Arc<Pool<ConnectionManager<PgConnection>>>;
+
+fn get_db_connection_pool() -> anyhow::Result<DBConn> {
+    log::info!("Connect to PostgresSQL database...");
+    let url = AppConfig::get().db_connection_chain();
+    let manager = ConnectionManager::<PgConnection>::new(url);
+    // Refer to the `r2d2` documentation for more methods to use
+    // when building a connection pool
+    Ok(Arc::new(
+        Pool::builder().test_on_check_out(true).build(manager)?,
+    ))
+}
+
+lazy_static! {
+    static ref DB_POOL: DBConn = get_db_connection_pool().expect("Failed to connect to database");
+}
+
+pub fn db() -> anyhow::Result<PooledConnection<ConnectionManager<PgConnection>>> {
+    Ok(DB_POOL.clone().get()?)
+}
+
+pub fn initialize_conn() -> anyhow::Result<()> {
+    // Run pending diesel migrations
+    let mut db = db()?;
+    db.run_pending_migrations(MIGRATIONS)
+        .expect("Failed to run DB migrations");
+
+    Ok(())
+}