From 4868929ff11d08ee39bddf96d3a1f445a8ba47d1 Mon Sep 17 00:00:00 2001
From: Joseph Glanville <jpg@jpg.id.au>
Date: Fri, 11 Sep 2015 03:05:39 +1000
Subject: [PATCH] ConnPool.Begin/BeginIso will retry if they Acquire a dead
 connection

---
 conn_pool.go | 52 ++++++++++++++++++++++++++++++++--------------------
 1 file changed, 32 insertions(+), 20 deletions(-)

diff --git a/conn_pool.go b/conn_pool.go
index 041ac830..0c5f87f7 100644
--- a/conn_pool.go
+++ b/conn_pool.go
@@ -214,34 +214,46 @@ func (p *ConnPool) QueryRow(sql string, args ...interface{}) *Row {
 // Begin acquires a connection and begins a transaction on it. When the
 // transaction is closed the connection will be automatically released.
 func (p *ConnPool) Begin() (*Tx, error) {
-	c, err := p.Acquire()
-	if err != nil {
-		return nil, err
-	}
+	for {
+		c, err := p.Acquire()
+		if err != nil {
+			return nil, err
+		}
 
-	tx, err := c.Begin()
-	if err != nil {
-		return nil, err
-	}
+		tx, err := c.Begin()
+		if err == ErrDeadConn {
+			p.Release(c)
+			continue
+		}
+		if err != nil {
+			return nil, err
+		}
 
-	tx.pool = p
-	return tx, nil
+		tx.pool = p
+		return tx, nil
+	}
 }
 
 // BeginIso acquires a connection and begins a transaction in isolation mode iso
 // on it. When the transaction is closed the connection will be automatically
 // released.
 func (p *ConnPool) BeginIso(iso string) (*Tx, error) {
-	c, err := p.Acquire()
-	if err != nil {
-		return nil, err
-	}
+	for {
+		c, err := p.Acquire()
+		if err != nil {
+			return nil, err
+		}
 
-	tx, err := c.BeginIso(iso)
-	if err != nil {
-		return nil, err
-	}
+		tx, err := c.BeginIso(iso)
+		if err == ErrDeadConn {
+			p.Release(c)
+			continue
+		}
+		if err != nil {
+			return nil, err
+		}
 
-	tx.pool = p
-	return tx, nil
+		tx.pool = p
+		return tx, nil
+	}
 }