From efa4a7888334cef41e97b1e0d80be54cb627d61b Mon Sep 17 00:00:00 2001
From: Patrick White <patrickwhite.256@gmail.com>
Date: Thu, 1 Aug 2019 14:59:53 -0700
Subject: [PATCH] Close single conn connection pool

---
 internal/error.go            |  7 +++++++
 internal/pool/pool_single.go | 16 ++++++++++++++--
 2 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/internal/error.go b/internal/error.go
index cd90d0d..a425574 100644
--- a/internal/error.go
+++ b/internal/error.go
@@ -2,6 +2,7 @@ package internal
 
 import (
 	"context"
+	"errors"
 	"io"
 	"net"
 	"strings"
@@ -9,6 +10,8 @@ import (
 	"github.com/go-redis/redis/internal/proto"
 )
 
+var ErrSingleConnPoolClosed = errors.New("redis: SingleConnPool is closed")
+
 func IsRetryableError(err error, retryTimeout bool) bool {
 	switch err {
 	case nil, context.Canceled, context.DeadlineExceeded:
@@ -22,6 +25,10 @@ func IsRetryableError(err error, retryTimeout bool) bool {
 		}
 		return true
 	}
+	if err == ErrSingleConnPoolClosed {
+		return true
+	}
+
 	s := err.Error()
 	if s == "ERR max number of clients reached" {
 		return true
diff --git a/internal/pool/pool_single.go b/internal/pool/pool_single.go
index fda1c8a..12542c6 100644
--- a/internal/pool/pool_single.go
+++ b/internal/pool/pool_single.go
@@ -1,9 +1,14 @@
 package pool
 
-import "context"
+import (
+	"context"
+
+	"github.com/go-redis/redis/internal"
+)
 
 type SingleConnPool struct {
-	cn *Conn
+	cn       *Conn
+	cnClosed bool
 }
 
 var _ Pooler = (*SingleConnPool)(nil)
@@ -23,6 +28,9 @@ func (p *SingleConnPool) CloseConn(*Conn) error {
 }
 
 func (p *SingleConnPool) Get(ctx context.Context) (*Conn, error) {
+	if p.cnClosed {
+		return nil, internal.ErrSingleConnPoolClosed
+	}
 	return p.cn, nil
 }
 
@@ -36,9 +44,13 @@ func (p *SingleConnPool) Remove(cn *Conn) {
 	if p.cn != cn {
 		panic("p.cn != cn")
 	}
+	p.cnClosed = true
 }
 
 func (p *SingleConnPool) Len() int {
+	if p.cnClosed {
+		return 0
+	}
 	return 1
 }