feat: support configure refinery to use redis in cluster mode

config/config.go

@@ -66,6 +66,10 @@ type Config interface {
 	// management.
 	GetRedisHost() string
 
+	// GetRedisClusterHosts returns the list of addresses of a Redis cluster, used for
+	// managing peer cluster membership.
+	GetRedisClusterHosts() []string
+
 	// GetRedisUsername returns the username of a Redis instance to use for peer
 	// management.
 	GetRedisUsername() string

config/config_test.go

@@ -12,6 +12,7 @@ import (
 	"github.com/honeycombio/refinery/internal/configwatcher"
 	"github.com/honeycombio/refinery/pubsub"
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 	"gopkg.in/yaml.v3"
 )
 
@@ -454,6 +455,27 @@ func TestDryRun(t *testing.T) {
 	}
 }
 
+func TestRedisClusterHosts(t *testing.T) {
+	clusterHosts := []string{"localhost:7001", "localhost:7002"}
+	cm := makeYAML(
+		"General.ConfigurationVersion", 2,
+		"PeerManagement.Type", "redis",
+		"RedisPeerManagement.ClusterHosts", clusterHosts,
+		"RedisPeerManagement.Prefix", "test",
+		"RedisPeerManagement.Database", 9,
+	)
+	rm := makeYAML("ConfigVersion", 2)
+	config, rules := createTempConfigs(t, cm, rm)
+	defer os.Remove(rules)
+	defer os.Remove(config)
+	c, err := getConfig([]string{"--no-validate", "--config", config, "--rules_config", rules})
+	assert.NoError(t, err)
+
+	d := c.GetRedisClusterHosts()
+	require.NotNil(t, d)
+	require.EqualValues(t, clusterHosts, d)
+}
+
 func TestMaxAlloc(t *testing.T) {
 	cm := makeYAML("General.ConfigurationVersion", 2, "Collection.CacheCapacity", 1000, "Collection.MaxAlloc", 17179869184)
 	rm := makeYAML("ConfigVersion", 2)

config/file_config.go

@@ -285,6 +285,7 @@ type PeerManagementConfig struct {
 
 type RedisPeerManagementConfig struct {
 	Host           string   `yaml:"Host" cmdenv:"RedisHost"`
+	ClusterHosts   []string `yaml:"ClusterHosts"`
 	Username       string   `yaml:"Username" cmdenv:"RedisUsername"`
 	Password       string   `yaml:"Password" cmdenv:"RedisPassword"`
 	AuthCode       string   `yaml:"AuthCode" cmdenv:"RedisAuthCode"`
@@ -653,6 +654,13 @@ func (f *fileConfig) GetRedisHost() string {
 	return f.mainConfig.RedisPeerManagement.Host
 }
 
+func (f *fileConfig) GetRedisClusterHosts() []string {
+	f.mux.RLock()
+	defer f.mux.RUnlock()
+
+	return f.mainConfig.RedisPeerManagement.ClusterHosts
+}
+
 func (f *fileConfig) GetRedisUsername() string {
 	f.mux.RLock()
 	defer f.mux.RUnlock()

config/metadata/configMeta.yaml

@@ -987,6 +987,20 @@ groups:
         description: >
           Must be in the form `host:port`.
 
+      - name: ClusterHosts
+        type: stringarray
+        valuetype: stringarray
+        example: "- localhost:6379"
+        firstversion: v2.8
+        validations:
+          - type: elementType
+            arg: hostport
+        reload: false
+        summary: is a list of host and port pairs for the instances in a Redis Cluster, used for managing peer cluster membership.
+        description: >
+          This configuration enables Refinery to connect to a Redis cluster. Each entry in the list should follow the format `host:port`.
+          If `ClusterHosts` is specified, the `Host` setting will be ignored.
+
       - name: Username
         v1group: PeerManagement
         v1name: RedisUsername
@@ -1253,6 +1267,7 @@ groups:
       - name: ShutdownDelay
         type: duration
         valuetype: nondefault
+        firstversion: v2.8
         default: 15s
         reload: true
         summary: controls the maximum time Refinery can use while draining traces at shutdown.

config/mock.go

@@ -27,6 +27,7 @@ type MockConfig struct {
 	GetLoggerLevelVal                Level
 	GetPeersVal                      []string
 	GetRedisHostVal                  string
+	GetRedisClusterHostsVal          []string
 	GetRedisUsernameVal              string
 	GetRedisPasswordVal              string
 	GetRedisAuthCodeVal              string
@@ -216,6 +217,12 @@ func (m *MockConfig) GetRedisHost() string {
 	return m.GetRedisHostVal
 }
 
+func (m *MockConfig) GetRedisClusterHosts() []string {
+	m.Mux.RLock()
+	defer m.Mux.RUnlock()
+
+	return m.GetRedisClusterHostsVal
+}
 func (m *MockConfig) GetRedisUsername() string {
 	m.Mux.RLock()
 	defer m.Mux.RUnlock()

pubsub/pubsub_goredis.go

@@ -3,7 +3,6 @@ package pubsub
 import (
 	"context"
 	"crypto/tls"
-	"strings"
 	"sync"
 
 	"go.opentelemetry.io/otel/trace"
@@ -58,14 +57,17 @@ func (ps *GoRedisPubSub) Start() error {
 
 	if ps.Config != nil {
 		host := ps.Config.GetRedisHost()
+		hosts := []string{host}
+		clusterHosts := ps.Config.GetRedisClusterHosts()
+		// if we have a cluster host, use that instead of the regular host
+		if len(clusterHosts) > 0 {
+			hosts = clusterHosts
+		}
+
 		username := ps.Config.GetRedisUsername()
 		pw := ps.Config.GetRedisPassword()
 		authcode = ps.Config.GetRedisAuthCode()
 
-		// we may have multiple hosts, separated by commas, so split them up and
-		// use them as the addrs for the client (if there are multiples, it will
-		// create a cluster client)
-		hosts := strings.Split(host, ",")
 		options.Addrs = hosts
 		options.Username = username
 		options.Password = pw