fix #141

bb8/src/api.rs

@@ -272,6 +272,7 @@ impl<M: ManageConnection> Builder<M> {
     /// minimum number of connections, or it times out.
     pub async fn build(self, manager: M) -> Result<Pool<M>, M::Error> {
         let pool = self.build_inner(manager);
+        pool.inner.preconnect().await?;
         pool.inner.start_connections().await.map(|()| pool)
     }
 

bb8/src/inner.rs

@@ -151,6 +151,10 @@ where
         Ok(conn)
     }
 
+    pub(crate) async fn preconnect(&self) -> Result<(), M::Error> {
+        self.inner.manager.connect().await.map(|_| ())
+    }
+
     /// Return connection back in to the pool
     pub(crate) fn put_back(&self, conn: Option<Conn<M::Connection>>) {
         let conn = conn.and_then(|mut conn| {

bb8/tests/test.rs

@@ -108,7 +108,7 @@ where
 
 #[tokio::test]
 async fn test_max_size_ok() {
-    let manager = NthConnectionFailManager::<FakeConnection>::new(5);
+    let manager = NthConnectionFailManager::<FakeConnection>::new(6);
     let pool = Pool::builder().max_size(5).build(manager).await.unwrap();
     let mut channels = Vec::with_capacity(5);
     let mut ignored = Vec::with_capacity(5);
@@ -409,7 +409,7 @@ async fn test_max_lifetime() {
         }
     }
 
-    let manager = NthConnectionFailManager::<Connection>::new(5);
+    let manager = NthConnectionFailManager::<Connection>::new(6);
     let pool = Pool::builder()
         .max_lifetime(Some(Duration::from_secs(1)))
         .connection_timeout(Duration::from_secs(1))
@@ -442,14 +442,14 @@ async fn test_max_lifetime() {
     assert!(timeout(Duration::from_secs(2), pending::<()>())
         .await
         .is_err());
-    assert_eq!(DROPPED.load(Ordering::SeqCst), 4);
+    assert_eq!(DROPPED.load(Ordering::SeqCst), 5);
     tx2.send(()).unwrap();
 
     // And wait some more.
     assert!(timeout(Duration::from_secs(2), pending::<()>())
         .await
         .is_err());
-    assert_eq!(DROPPED.load(Ordering::SeqCst), 5);
+    assert_eq!(DROPPED.load(Ordering::SeqCst), 6);
 }
 
 #[tokio::test]
@@ -550,7 +550,7 @@ async fn test_conns_drop_on_pool_drop() {
     drop(pool);
 
     for _ in 0u8..10 {
-        if DROPPED.load(Ordering::SeqCst) == 10 {
+        if DROPPED.load(Ordering::SeqCst) == 11 {
             return;
         }
 
@@ -626,7 +626,7 @@ async fn test_conn_fail_once() {
 
         async fn connect(&self) -> Result<Self::Connection, Self::Error> {
             // only fail once so the retry should work
-            if FAILED_ONCE.load(Ordering::SeqCst) {
+            if FAILED_ONCE.load(Ordering::SeqCst) || NB_CALL.load(Ordering::SeqCst) == 0 {
                 Ok(Connection)
             } else {
                 FAILED_ONCE.store(true, Ordering::SeqCst);