Merge pull request #1546 from 1819997197/fix-1545

sessions: database: redis: fix clustering
Former-commit-id: 063e026a06f61a0a1414bb8d97361bf7a6e8601c

sessions/sessiondb/redis/database.go

@@ -31,7 +31,6 @@ type Config struct {
 	Addr string
 	// Clusters a list of network addresses for clusters.
 	// If not empty "Addr" is ignored.
-	// Currently only Radix() Driver supports it.
 	Clusters []string
 	// Password string .If no password then no 'AUTH'. Defaults to "".
 	Password string
@@ -119,8 +118,7 @@ func New(cfg ...Config) *Database {
 	db := &Database{c: c}
 	_, err := db.c.Driver.PingPong()
 	if err != nil {
-		golog.Debugf("error connecting to redis: %v", err)
-		return nil
+		panic(err)
 	}
 	// runtime.SetFinalizer(db, closeDB)
 	return db

sessions/sessiondb/redis/driver_radix.go

@@ -4,13 +4,18 @@ import (
 	"bufio"
 	"errors"
 	"fmt"
-	"math/rand"
 	"strconv"
 
 	"github.com/mediocregopher/radix/v3"
 	"github.com/mediocregopher/radix/v3/resp/resp2"
 )
 
+// radixPool an interface to complete both *radix.Pool and *radix.Cluster.
+type radixPool interface {
+	Do(a radix.Action) error
+	Close() error
+}
+
 // RadixDriver the Redis service based on the radix go client,
 // contains the config and the redis pool.
 type RadixDriver struct {
@@ -18,7 +23,7 @@ type RadixDriver struct {
 	Connected bool
 	// Config the read-only redis database config.
 	Config Config
-	pool   *radix.Pool
+	pool   radixPool
 }
 
 // Connect connects to the redis, called only once
@@ -70,6 +75,12 @@ func (r *RadixDriver) Connect(c Config) error {
 
 	var connFunc radix.ConnFunc
 
+	/* Note(@kataras): according to #1545 the below does NOT work, and we should
+	use the Cluster instance itself to fire requests.
+	We need a separate `radix.Cluster` instance to do the calls,
+	fortunally both Pool and Cluster implement the same Do and Close methods we need,
+	so a new `radixPool` interface to remove any dupl code is used instead.
+
 	if len(c.Clusters) > 0 {
 		cluster, err := radix.NewCluster(c.Clusters)
 		if err != nil {
@@ -84,14 +95,31 @@ func (r *RadixDriver) Connect(c Config) error {
 			return radix.Dial(c.Network, node.Addr, options...)
 		}
 	} else {
-		connFunc = func(network, addr string) (radix.Conn, error) {
-			return radix.Dial(c.Network, c.Addr, options...)
-		}
+	*/
+	connFunc = func(network, addr string) (radix.Conn, error) {
+		return radix.Dial(c.Network, c.Addr, options...)
 	}
 
-	pool, err := radix.NewPool(c.Network, c.Addr, c.MaxActive, radix.PoolConnFunc(connFunc))
-	if err != nil {
-		return err
+	var pool radixPool
+
+	if len(c.Clusters) > 0 {
+		poolFunc := func(network, addr string) (radix.Client, error) {
+			return radix.NewPool(network, addr, c.MaxActive, radix.PoolConnFunc(connFunc))
+		}
+
+		cluster, err := radix.NewCluster(c.Clusters, radix.ClusterPoolFunc(poolFunc))
+		if err != nil {
+			return err
+		}
+
+		pool = cluster
+	} else {
+		p, err := radix.NewPool(c.Network, c.Addr, c.MaxActive, radix.PoolConnFunc(connFunc))
+		if err != nil {
+			return err
+		}
+
+		pool = p
 	}
 
 	r.Connected = true