From 7333f0a0d2e17ee697b3849be08238c33c378966 Mon Sep 17 00:00:00 2001
From: Harmen <alicebob@lijzij.de>
Date: Mon, 15 Jan 2018 15:47:22 +0100
Subject: [PATCH] m.redigo(), to avoid a TCP connection in Lua

Not public to keep the redigo stuff internal
---
 cmd_scripting.go  |  9 +--------
 miniredis.go      | 10 ++++++++++
 miniredis_test.go | 18 ++++++++++++++++++
 server/server.go  | 35 ++++++++++++++++++++---------------
 4 files changed, 49 insertions(+), 23 deletions(-)

diff --git a/cmd_scripting.go b/cmd_scripting.go
index 2e645d43..f7a01fed 100644
--- a/cmd_scripting.go
+++ b/cmd_scripting.go
@@ -3,12 +3,10 @@ package miniredis
 import (
 	"crypto/sha1"
 	"encoding/hex"
-	"fmt"
 	"io"
 	"strconv"
 	"strings"
 
-	"github.com/garyburd/redigo/redis"
 	lua "github.com/yuin/gopher-lua"
 	"github.com/yuin/gopher-lua/parse"
 
@@ -25,12 +23,7 @@ func (m *Miniredis) runLuaScript(c *server.Peer, script string, args []string) {
 	l := lua.NewState()
 	defer l.Close()
 
-	// create a redis client for redis.call
-	conn, err := redis.Dial("tcp", m.srv.Addr().String())
-	if err != nil {
-		c.WriteError(fmt.Sprintf("ERR Redis error: %v", err.Error()))
-		return
-	}
+	conn := m.redigo()
 	defer conn.Close()
 
 	// set global variable KEYS
diff --git a/miniredis.go b/miniredis.go
index 9a016f0f..0370d0bd 100644
--- a/miniredis.go
+++ b/miniredis.go
@@ -16,10 +16,13 @@ package miniredis
 
 import (
 	"fmt"
+	"net"
 	"strconv"
 	"sync"
 	"time"
 
+	redigo "github.com/garyburd/redigo/redis"
+
 	"github.com/alicebob/miniredis/server"
 )
 
@@ -237,6 +240,13 @@ func (m *Miniredis) FastForward(duration time.Duration) {
 	}
 }
 
+// redigo returns a redigo.Conn, connected using net.Pipe
+func (m *Miniredis) redigo() redigo.Conn {
+	c1, c2 := net.Pipe()
+	m.srv.ServeConn(c1)
+	return redigo.NewConn(c2, 0, 0)
+}
+
 // Dump returns a text version of the selected DB, usable for debugging.
 func (m *Miniredis) Dump() string {
 	m.Lock()
diff --git a/miniredis_test.go b/miniredis_test.go
index bac7ddd6..a79aa23f 100644
--- a/miniredis_test.go
+++ b/miniredis_test.go
@@ -211,3 +211,21 @@ func TestExpireWithFastForward(t *testing.T) {
 	s.FastForward(5 * time.Second)
 	equals(t, 1, len(s.Keys()))
 }
+
+func TestRedigo(t *testing.T) {
+	s, err := Run()
+	ok(t, err)
+
+	r := s.redigo()
+	defer r.Close()
+
+	_, err = r.Do("SELECT", 2)
+	ok(t, err)
+
+	_, err = r.Do("SET", "foo", "bar")
+	ok(t, err)
+
+	v, err := redis.String(r.Do("GET", "foo"))
+	ok(t, err)
+	equals(t, "bar", v)
+}
diff --git a/server/server.go b/server/server.go
index fb130afc..69ee67e3 100644
--- a/server/server.go
+++ b/server/server.go
@@ -54,24 +54,29 @@ func (s *Server) serve(l net.Listener) {
 		if err != nil {
 			return
 		}
-		s.wg.Add(1)
-		go func() {
-			defer s.wg.Done()
-			defer conn.Close()
-			s.mu.Lock()
-			s.peers[conn] = struct{}{}
-			s.infoConns++
-			s.mu.Unlock()
-
-			s.servePeer(conn)
-
-			s.mu.Lock()
-			delete(s.peers, conn)
-			s.mu.Unlock()
-		}()
+		s.ServeConn(conn)
 	}
 }
 
+// ServeConn handles a net.Conn. Nice with net.Pipe()
+func (s *Server) ServeConn(conn net.Conn) {
+	s.wg.Add(1)
+	go func() {
+		defer s.wg.Done()
+		defer conn.Close()
+		s.mu.Lock()
+		s.peers[conn] = struct{}{}
+		s.infoConns++
+		s.mu.Unlock()
+
+		s.servePeer(conn)
+
+		s.mu.Lock()
+		delete(s.peers, conn)
+		s.mu.Unlock()
+	}()
+}
+
 // Addr has the net.Addr struct
 func (s *Server) Addr() *net.TCPAddr {
 	s.mu.Lock()