GeneIT/geneit_backend/src/connections/db_connection.rs

42 lines
1.4 KiB
Rust

//! # Database connection management
use crate::app_config::AppConfig;
use diesel::result::{DatabaseErrorKind, Error};
use diesel::{Connection, PgConnection};
use std::cell::RefCell;
thread_local! {
static POSTGRES_CONNECTION: RefCell<Option<PgConnection>> = RefCell::new(None);
}
/// Execute a request on the database
pub fn execute<E, I>(cb: E) -> anyhow::Result<I>
where
E: FnOnce(&mut PgConnection) -> diesel::QueryResult<I>,
{
// Establish connection if required
if POSTGRES_CONNECTION.with(|i| i.borrow().is_none()) {
let database_url = AppConfig::get().db_connection_chain();
let conn = PgConnection::establish(&database_url)
.unwrap_or_else(|_| panic!("Error connecting to {}", database_url));
POSTGRES_CONNECTION.with(|i| *i.borrow_mut() = Some(conn))
}
match POSTGRES_CONNECTION.with(|i| cb(i.borrow_mut().as_mut().unwrap())) {
Ok(res) => Ok(res),
Err(e) => {
if matches!(
e,
Error::DatabaseError(DatabaseErrorKind::ClosedConnection, _)
| Error::BrokenTransactionManager
) {
log::warn!("Connection to database closed, dropping handle!");
POSTGRES_CONNECTION.with(|i| *i.borrow_mut() = None)
}
log::error!("Database query error! {:?}", e);
Err(e.into())
}
}
}