client constructor overhaul + configuration exposure

Author: pascaldekloe

README.md

@@ -26,7 +26,7 @@ Version 2 [github.com/pascaldekloe/redis/v2] utilizes generics.
 
 ```go
 // Redis is a thread-safe connection establishment.
-var Redis = redis.NewClient[string,string]("rds1.example.com", time.Second/2, 0)
+var Redis = redis.NewDefaultClient[string,string]("rds1.example.com")
 
 // Grow adds a string to a list.
 func Grow() {

client.go

@@ -24,7 +24,7 @@ const (
 var errConnLost = errors.New("redis: connection lost while awaiting response")
 
 // ClientConfig defines a Client setup.
-type ClientConfig[Key, Value String] struct {
+type ClientConfig struct {
 	// The host defaults to localhost, and the port defaults to 6379.
 	// Thus, the empty string defaults to "localhost:6379". Use an
 	// absolute file path (e.g. "/var/run/redis.sock") for Unix
@@ -51,21 +51,13 @@ type ClientConfig[Key, Value String] struct {
 	DB int64
 }
 
-// NewClient launches a managed connection to a node (address).
-func (c *ClientConfig[Key, Value]) NewClient() *Client[Key, Value] {
-	return newClient(*c)
-}
-
 // Client manages a connection to a Redis node until Close. Broken connection
 // states cause automated reconnects.
 //
 // Multiple goroutines may invoke methods on a Client simultaneously. Command
 // invocation applies <https://redis.io/topics/pipelining> on concurrency.
 type Client[Key, Value String] struct {
-	// Normalized node address in use. This field is read-only.
-	Addr string
-
-	config ClientConfig[Key, Value]
+	ClientConfig // read-only attributes
 
 	noCopy noCopy
 
@@ -85,29 +77,18 @@ type Client[Key, Value String] struct {
 	readTerm chan struct{}
 }
 
-// NewClient launches a managed connection to a node (address).
-// The host defaults to localhost, and the port defaults to 6379.
-// Thus, the empty string defaults to "localhost:6379". Use an
-// absolute file path (e.g. "/var/run/redis.sock") for Unix
-// domain sockets.
-//
-// A command time-out limits execution duration when nonzero. Expiry causes a
-// reconnect (to prevent stale connections) and a net.Error with Timeout() true.
-//
-// The dial time-out limits the duration for network connection establishment.
-// Expiry causes an abort + retry. Zero defaults to one second. Any command
-// submission blocks on the first attempt. When connection establishment fails,
-// then command submission receives the error of the last attempt, until the
-// connection restores.
-func NewClient[Key, Value String](addr string, commandTimeout, dialTimeout time.Duration) *Client[Key, Value] {
-	return newClient(ClientConfig[Key, Value]{
+// NewDefaultClient launches a managed connection to a node (address).
+// Both CommandTimeout and DialTimeout are set to one second.
+func NewDefaultClient[Key, Value String](addr string) *Client[Key, Value] {
+	return NewClient[Key, Value](ClientConfig{
 		Addr:           addr,
-		CommandTimeout: commandTimeout,
-		DialTimeout:    dialTimeout,
+		CommandTimeout: time.Second,
+		DialTimeout:    time.Second,
 	})
 }
 
-func newClient[Key, Value String](config ClientConfig[Key, Value]) *Client[Key, Value] {
+// NewClient launches a managed connection to a node (address).
+func NewClient[Key, Value String](config ClientConfig) *Client[Key, Value] {
 	config.Addr = normalizeAddr(config.Addr)
 	if config.DialTimeout == 0 {
 		config.DialTimeout = time.Second
@@ -119,8 +100,7 @@ func newClient[Key, Value String](config ClientConfig[Key, Value]) *Client[Key,
 	}
 
 	c := &Client[Key, Value]{
-		Addr:   config.Addr, // decouple
-		config: config,
+		ClientConfig: config,
 
 		connSem:   make(chan *redisConn, 1),
 		readQueue: make(chan chan<- *bufio.Reader, queueSize),
@@ -172,7 +152,7 @@ func (c *Client[Key, Value]) Close() error {
 func (c *Client[Key, Value]) connectOrClosed() {
 	var retryDelay time.Duration
 	for {
-		conn, reader, err := c.config.connect(conservativeMSS)
+		conn, reader, err := c.connect(conservativeMSS)
 		if err != nil {
 			retry := time.NewTimer(retryDelay)
 
@@ -237,8 +217,8 @@ func (c *Client[Key, Value]) exchange(req *request) (*bufio.Reader, error) {
 
 	// apply time-out if set
 	var deadline time.Time
-	if c.config.CommandTimeout != 0 {
-		deadline = time.Now().Add(c.config.CommandTimeout)
+	if c.CommandTimeout != 0 {
+		deadline = time.Now().Add(c.CommandTimeout)
 		conn.SetWriteDeadline(deadline)
 	}
 
@@ -430,7 +410,7 @@ func (c *Client[Key, Value]) dropConnFromRead() {
 	}
 }
 
-func (c *ClientConfig[Key, Value]) connect(readBufferSize int) (net.Conn, *bufio.Reader, error) {
+func (c *ClientConfig) connect(readBufferSize int) (net.Conn, *bufio.Reader, error) {
 	network := "tcp"
 	if isUnixAddr(c.Addr) {
 		network = "unix"

client_test.go

@@ -14,35 +14,29 @@ import (
 	"time"
 )
 
-var testConfig ClientConfig[string, string]
 var testClient, benchClient *Client[string, string]
 
 func init() {
 	addr, ok := os.LookupEnv("TEST_REDIS_ADDR")
 	if !ok {
 		log.Fatal("Need TEST_REDIS_ADDR evironment variable with an address of a test server.\nCAUTION! Tests insert, modify and delete data.")
 	}
-	testConfig.Addr = addr
-
+	config := ClientConfig{Addr: addr}
 	if s, ok := os.LookupEnv("TEST_REDIS_PASSWORD"); ok {
-		testConfig.Password = []byte(s)
+		config.Password = []byte(s)
 	}
 
-	benchClient = testConfig.NewClient()
+	benchClient = NewClient[string, string](config)
 
-	testConfig.CommandTimeout = time.Second
-	testClient = testConfig.NewClient()
+	config.CommandTimeout = time.Second
+	testClient = NewClient[string, string](config)
 
 	// make random keys vary
 	rand.Seed(time.Now().UnixNano())
 }
 
 func byteValueClient(t testing.TB) *Client[string, []byte] {
-	config := ClientConfig[string, []byte]{
-		Addr:     testConfig.Addr,
-		Password: testConfig.Password,
-	}
-	c := config.NewClient()
+	c := NewClient[string, []byte](testClient.ClientConfig)
 	t.Cleanup(func() {
 		err := c.Close()
 		if err != nil {
@@ -58,7 +52,7 @@ func randomKey(prefix string) string {
 
 func TestClose(t *testing.T) {
 	t.Parallel()
-	c := NewClient[string, string](testClient.Addr, 0, 0)
+	c := NewDefaultClient[string, string](testClient.Addr)
 	if err := c.Close(); err != nil {
 		t.Fatal("close got error:", err)
 	}
@@ -74,7 +68,7 @@ func TestClose(t *testing.T) {
 
 func TestCloseBussy(t *testing.T) {
 	t.Parallel()
-	c := testConfig.NewClient()
+	c := NewClient[string, string](testClient.ClientConfig)
 	key := randomKey("counter")
 
 	timeout := time.NewTimer(time.Second)
@@ -115,9 +109,10 @@ func TestCloseBussy(t *testing.T) {
 func TestUnavailable(t *testing.T) {
 	t.Parallel()
 
-	connectTimeout := 100 * time.Millisecond
-
-	c := NewClient[string, string]("doesnotexist.example.com:70", 0, connectTimeout)
+	config := testClient.ClientConfig
+	config.Addr = "doesnotexist.example.com:70"
+	config.DialTimeout = 100 * time.Millisecond
+	c := NewClient[string, string](config)
 	defer func() {
 		if err := c.Close(); err != nil {
 			t.Error("close got error:", err)
@@ -136,7 +131,7 @@ func TestUnavailable(t *testing.T) {
 	}
 
 	// let the Client retry…
-	time.Sleep(2 * connectTimeout)
+	time.Sleep(2 * config.DialTimeout)
 
 	_, err = c.GET("arbitrary")
 	if e := new(net.OpError); !errors.As(err, &e) {

example_test.go

@@ -10,7 +10,7 @@ import (
 
 func ExampleClient_SETWithOptions() {
 	// connection setup
-	var Redis = redis.NewClient[string, string]("rds1.example.com", time.Second/2, 0)
+	var Redis = redis.NewDefaultClient[string, string]("rds1.example.com")
 	defer Redis.Close()
 
 	// execute command

pubsub.go

@@ -222,7 +222,7 @@ func (l *Listener) connectLoop() {
 
 	var retryDelay time.Duration
 	for {
-		config := ClientConfig[string, string]{
+		config := ClientConfig{
 			Addr:           l.Addr,
 			CommandTimeout: l.CommandTimeout,
 			DialTimeout:    l.DialTimeout,

pubsub_test.go

@@ -47,10 +47,10 @@ func newTestListener(t *testing.T) (*Listener, <-chan *listenerCall) {
 			}
 		},
 
-		Addr:           testConfig.Addr,
-		CommandTimeout: testConfig.CommandTimeout,
-		DialTimeout:    testConfig.DialTimeout,
-		Password:       testConfig.Password,
+		Addr:           testClient.Addr,
+		CommandTimeout: testClient.CommandTimeout,
+		DialTimeout:    testClient.DialTimeout,
+		Password:       testClient.Password,
 	})
 
 	t.Cleanup(func() {
@@ -329,10 +329,10 @@ func benchmarkPubSub(b *testing.B, size, routineN int) {
 				close(done)
 			}
 		},
-		Addr:           testConfig.Addr,
-		CommandTimeout: testConfig.CommandTimeout,
-		DialTimeout:    testConfig.DialTimeout,
-		Password:       testConfig.Password,
+		Addr:           testClient.Addr,
+		CommandTimeout: testClient.CommandTimeout,
+		DialTimeout:    testClient.DialTimeout,
+		Password:       testClient.Password,
 	})
 	defer l.Close()