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-rw-r--r--dependencies/pkg/mod/github.com/go-redis/redis/v8@v8.11.5/pubsub.go668
1 files changed, 668 insertions, 0 deletions
diff --git a/dependencies/pkg/mod/github.com/go-redis/redis/v8@v8.11.5/pubsub.go b/dependencies/pkg/mod/github.com/go-redis/redis/v8@v8.11.5/pubsub.go
new file mode 100644
index 0000000..efc2354
--- /dev/null
+++ b/dependencies/pkg/mod/github.com/go-redis/redis/v8@v8.11.5/pubsub.go
@@ -0,0 +1,668 @@
+package redis
+
+import (
+ "context"
+ "fmt"
+ "strings"
+ "sync"
+ "time"
+
+ "github.com/go-redis/redis/v8/internal"
+ "github.com/go-redis/redis/v8/internal/pool"
+ "github.com/go-redis/redis/v8/internal/proto"
+)
+
+// PubSub implements Pub/Sub commands as described in
+// http://redis.io/topics/pubsub. Message receiving is NOT safe
+// for concurrent use by multiple goroutines.
+//
+// PubSub automatically reconnects to Redis Server and resubscribes
+// to the channels in case of network errors.
+type PubSub struct {
+ opt *Options
+
+ newConn func(ctx context.Context, channels []string) (*pool.Conn, error)
+ closeConn func(*pool.Conn) error
+
+ mu sync.Mutex
+ cn *pool.Conn
+ channels map[string]struct{}
+ patterns map[string]struct{}
+
+ closed bool
+ exit chan struct{}
+
+ cmd *Cmd
+
+ chOnce sync.Once
+ msgCh *channel
+ allCh *channel
+}
+
+func (c *PubSub) init() {
+ c.exit = make(chan struct{})
+}
+
+func (c *PubSub) String() string {
+ channels := mapKeys(c.channels)
+ channels = append(channels, mapKeys(c.patterns)...)
+ return fmt.Sprintf("PubSub(%s)", strings.Join(channels, ", "))
+}
+
+func (c *PubSub) connWithLock(ctx context.Context) (*pool.Conn, error) {
+ c.mu.Lock()
+ cn, err := c.conn(ctx, nil)
+ c.mu.Unlock()
+ return cn, err
+}
+
+func (c *PubSub) conn(ctx context.Context, newChannels []string) (*pool.Conn, error) {
+ if c.closed {
+ return nil, pool.ErrClosed
+ }
+ if c.cn != nil {
+ return c.cn, nil
+ }
+
+ channels := mapKeys(c.channels)
+ channels = append(channels, newChannels...)
+
+ cn, err := c.newConn(ctx, channels)
+ if err != nil {
+ return nil, err
+ }
+
+ if err := c.resubscribe(ctx, cn); err != nil {
+ _ = c.closeConn(cn)
+ return nil, err
+ }
+
+ c.cn = cn
+ return cn, nil
+}
+
+func (c *PubSub) writeCmd(ctx context.Context, cn *pool.Conn, cmd Cmder) error {
+ return cn.WithWriter(ctx, c.opt.WriteTimeout, func(wr *proto.Writer) error {
+ return writeCmd(wr, cmd)
+ })
+}
+
+func (c *PubSub) resubscribe(ctx context.Context, cn *pool.Conn) error {
+ var firstErr error
+
+ if len(c.channels) > 0 {
+ firstErr = c._subscribe(ctx, cn, "subscribe", mapKeys(c.channels))
+ }
+
+ if len(c.patterns) > 0 {
+ err := c._subscribe(ctx, cn, "psubscribe", mapKeys(c.patterns))
+ if err != nil && firstErr == nil {
+ firstErr = err
+ }
+ }
+
+ return firstErr
+}
+
+func mapKeys(m map[string]struct{}) []string {
+ s := make([]string, len(m))
+ i := 0
+ for k := range m {
+ s[i] = k
+ i++
+ }
+ return s
+}
+
+func (c *PubSub) _subscribe(
+ ctx context.Context, cn *pool.Conn, redisCmd string, channels []string,
+) error {
+ args := make([]interface{}, 0, 1+len(channels))
+ args = append(args, redisCmd)
+ for _, channel := range channels {
+ args = append(args, channel)
+ }
+ cmd := NewSliceCmd(ctx, args...)
+ return c.writeCmd(ctx, cn, cmd)
+}
+
+func (c *PubSub) releaseConnWithLock(
+ ctx context.Context,
+ cn *pool.Conn,
+ err error,
+ allowTimeout bool,
+) {
+ c.mu.Lock()
+ c.releaseConn(ctx, cn, err, allowTimeout)
+ c.mu.Unlock()
+}
+
+func (c *PubSub) releaseConn(ctx context.Context, cn *pool.Conn, err error, allowTimeout bool) {
+ if c.cn != cn {
+ return
+ }
+ if isBadConn(err, allowTimeout, c.opt.Addr) {
+ c.reconnect(ctx, err)
+ }
+}
+
+func (c *PubSub) reconnect(ctx context.Context, reason error) {
+ _ = c.closeTheCn(reason)
+ _, _ = c.conn(ctx, nil)
+}
+
+func (c *PubSub) closeTheCn(reason error) error {
+ if c.cn == nil {
+ return nil
+ }
+ if !c.closed {
+ internal.Logger.Printf(c.getContext(), "redis: discarding bad PubSub connection: %s", reason)
+ }
+ err := c.closeConn(c.cn)
+ c.cn = nil
+ return err
+}
+
+func (c *PubSub) Close() error {
+ c.mu.Lock()
+ defer c.mu.Unlock()
+
+ if c.closed {
+ return pool.ErrClosed
+ }
+ c.closed = true
+ close(c.exit)
+
+ return c.closeTheCn(pool.ErrClosed)
+}
+
+// Subscribe the client to the specified channels. It returns
+// empty subscription if there are no channels.
+func (c *PubSub) Subscribe(ctx context.Context, channels ...string) error {
+ c.mu.Lock()
+ defer c.mu.Unlock()
+
+ err := c.subscribe(ctx, "subscribe", channels...)
+ if c.channels == nil {
+ c.channels = make(map[string]struct{})
+ }
+ for _, s := range channels {
+ c.channels[s] = struct{}{}
+ }
+ return err
+}
+
+// PSubscribe the client to the given patterns. It returns
+// empty subscription if there are no patterns.
+func (c *PubSub) PSubscribe(ctx context.Context, patterns ...string) error {
+ c.mu.Lock()
+ defer c.mu.Unlock()
+
+ err := c.subscribe(ctx, "psubscribe", patterns...)
+ if c.patterns == nil {
+ c.patterns = make(map[string]struct{})
+ }
+ for _, s := range patterns {
+ c.patterns[s] = struct{}{}
+ }
+ return err
+}
+
+// Unsubscribe the client from the given channels, or from all of
+// them if none is given.
+func (c *PubSub) Unsubscribe(ctx context.Context, channels ...string) error {
+ c.mu.Lock()
+ defer c.mu.Unlock()
+
+ for _, channel := range channels {
+ delete(c.channels, channel)
+ }
+ err := c.subscribe(ctx, "unsubscribe", channels...)
+ return err
+}
+
+// PUnsubscribe the client from the given patterns, or from all of
+// them if none is given.
+func (c *PubSub) PUnsubscribe(ctx context.Context, patterns ...string) error {
+ c.mu.Lock()
+ defer c.mu.Unlock()
+
+ for _, pattern := range patterns {
+ delete(c.patterns, pattern)
+ }
+ err := c.subscribe(ctx, "punsubscribe", patterns...)
+ return err
+}
+
+func (c *PubSub) subscribe(ctx context.Context, redisCmd string, channels ...string) error {
+ cn, err := c.conn(ctx, channels)
+ if err != nil {
+ return err
+ }
+
+ err = c._subscribe(ctx, cn, redisCmd, channels)
+ c.releaseConn(ctx, cn, err, false)
+ return err
+}
+
+func (c *PubSub) Ping(ctx context.Context, payload ...string) error {
+ args := []interface{}{"ping"}
+ if len(payload) == 1 {
+ args = append(args, payload[0])
+ }
+ cmd := NewCmd(ctx, args...)
+
+ c.mu.Lock()
+ defer c.mu.Unlock()
+
+ cn, err := c.conn(ctx, nil)
+ if err != nil {
+ return err
+ }
+
+ err = c.writeCmd(ctx, cn, cmd)
+ c.releaseConn(ctx, cn, err, false)
+ return err
+}
+
+// Subscription received after a successful subscription to channel.
+type Subscription struct {
+ // Can be "subscribe", "unsubscribe", "psubscribe" or "punsubscribe".
+ Kind string
+ // Channel name we have subscribed to.
+ Channel string
+ // Number of channels we are currently subscribed to.
+ Count int
+}
+
+func (m *Subscription) String() string {
+ return fmt.Sprintf("%s: %s", m.Kind, m.Channel)
+}
+
+// Message received as result of a PUBLISH command issued by another client.
+type Message struct {
+ Channel string
+ Pattern string
+ Payload string
+ PayloadSlice []string
+}
+
+func (m *Message) String() string {
+ return fmt.Sprintf("Message<%s: %s>", m.Channel, m.Payload)
+}
+
+// Pong received as result of a PING command issued by another client.
+type Pong struct {
+ Payload string
+}
+
+func (p *Pong) String() string {
+ if p.Payload != "" {
+ return fmt.Sprintf("Pong<%s>", p.Payload)
+ }
+ return "Pong"
+}
+
+func (c *PubSub) newMessage(reply interface{}) (interface{}, error) {
+ switch reply := reply.(type) {
+ case string:
+ return &Pong{
+ Payload: reply,
+ }, nil
+ case []interface{}:
+ switch kind := reply[0].(string); kind {
+ case "subscribe", "unsubscribe", "psubscribe", "punsubscribe":
+ // Can be nil in case of "unsubscribe".
+ channel, _ := reply[1].(string)
+ return &Subscription{
+ Kind: kind,
+ Channel: channel,
+ Count: int(reply[2].(int64)),
+ }, nil
+ case "message":
+ switch payload := reply[2].(type) {
+ case string:
+ return &Message{
+ Channel: reply[1].(string),
+ Payload: payload,
+ }, nil
+ case []interface{}:
+ ss := make([]string, len(payload))
+ for i, s := range payload {
+ ss[i] = s.(string)
+ }
+ return &Message{
+ Channel: reply[1].(string),
+ PayloadSlice: ss,
+ }, nil
+ default:
+ return nil, fmt.Errorf("redis: unsupported pubsub message payload: %T", payload)
+ }
+ case "pmessage":
+ return &Message{
+ Pattern: reply[1].(string),
+ Channel: reply[2].(string),
+ Payload: reply[3].(string),
+ }, nil
+ case "pong":
+ return &Pong{
+ Payload: reply[1].(string),
+ }, nil
+ default:
+ return nil, fmt.Errorf("redis: unsupported pubsub message: %q", kind)
+ }
+ default:
+ return nil, fmt.Errorf("redis: unsupported pubsub message: %#v", reply)
+ }
+}
+
+// ReceiveTimeout acts like Receive but returns an error if message
+// is not received in time. This is low-level API and in most cases
+// Channel should be used instead.
+func (c *PubSub) ReceiveTimeout(ctx context.Context, timeout time.Duration) (interface{}, error) {
+ if c.cmd == nil {
+ c.cmd = NewCmd(ctx)
+ }
+
+ // Don't hold the lock to allow subscriptions and pings.
+
+ cn, err := c.connWithLock(ctx)
+ if err != nil {
+ return nil, err
+ }
+
+ err = cn.WithReader(ctx, timeout, func(rd *proto.Reader) error {
+ return c.cmd.readReply(rd)
+ })
+
+ c.releaseConnWithLock(ctx, cn, err, timeout > 0)
+
+ if err != nil {
+ return nil, err
+ }
+
+ return c.newMessage(c.cmd.Val())
+}
+
+// Receive returns a message as a Subscription, Message, Pong or error.
+// See PubSub example for details. This is low-level API and in most cases
+// Channel should be used instead.
+func (c *PubSub) Receive(ctx context.Context) (interface{}, error) {
+ return c.ReceiveTimeout(ctx, 0)
+}
+
+// ReceiveMessage returns a Message or error ignoring Subscription and Pong
+// messages. This is low-level API and in most cases Channel should be used
+// instead.
+func (c *PubSub) ReceiveMessage(ctx context.Context) (*Message, error) {
+ for {
+ msg, err := c.Receive(ctx)
+ if err != nil {
+ return nil, err
+ }
+
+ switch msg := msg.(type) {
+ case *Subscription:
+ // Ignore.
+ case *Pong:
+ // Ignore.
+ case *Message:
+ return msg, nil
+ default:
+ err := fmt.Errorf("redis: unknown message: %T", msg)
+ return nil, err
+ }
+ }
+}
+
+func (c *PubSub) getContext() context.Context {
+ if c.cmd != nil {
+ return c.cmd.ctx
+ }
+ return context.Background()
+}
+
+//------------------------------------------------------------------------------
+
+// Channel returns a Go channel for concurrently receiving messages.
+// The channel is closed together with the PubSub. If the Go channel
+// is blocked full for 30 seconds the message is dropped.
+// Receive* APIs can not be used after channel is created.
+//
+// go-redis periodically sends ping messages to test connection health
+// and re-subscribes if ping can not not received for 30 seconds.
+func (c *PubSub) Channel(opts ...ChannelOption) <-chan *Message {
+ c.chOnce.Do(func() {
+ c.msgCh = newChannel(c, opts...)
+ c.msgCh.initMsgChan()
+ })
+ if c.msgCh == nil {
+ err := fmt.Errorf("redis: Channel can't be called after ChannelWithSubscriptions")
+ panic(err)
+ }
+ return c.msgCh.msgCh
+}
+
+// ChannelSize is like Channel, but creates a Go channel
+// with specified buffer size.
+//
+// Deprecated: use Channel(WithChannelSize(size)), remove in v9.
+func (c *PubSub) ChannelSize(size int) <-chan *Message {
+ return c.Channel(WithChannelSize(size))
+}
+
+// ChannelWithSubscriptions is like Channel, but message type can be either
+// *Subscription or *Message. Subscription messages can be used to detect
+// reconnections.
+//
+// ChannelWithSubscriptions can not be used together with Channel or ChannelSize.
+func (c *PubSub) ChannelWithSubscriptions(_ context.Context, size int) <-chan interface{} {
+ c.chOnce.Do(func() {
+ c.allCh = newChannel(c, WithChannelSize(size))
+ c.allCh.initAllChan()
+ })
+ if c.allCh == nil {
+ err := fmt.Errorf("redis: ChannelWithSubscriptions can't be called after Channel")
+ panic(err)
+ }
+ return c.allCh.allCh
+}
+
+type ChannelOption func(c *channel)
+
+// WithChannelSize specifies the Go chan size that is used to buffer incoming messages.
+//
+// The default is 100 messages.
+func WithChannelSize(size int) ChannelOption {
+ return func(c *channel) {
+ c.chanSize = size
+ }
+}
+
+// WithChannelHealthCheckInterval specifies the health check interval.
+// PubSub will ping Redis Server if it does not receive any messages within the interval.
+// To disable health check, use zero interval.
+//
+// The default is 3 seconds.
+func WithChannelHealthCheckInterval(d time.Duration) ChannelOption {
+ return func(c *channel) {
+ c.checkInterval = d
+ }
+}
+
+// WithChannelSendTimeout specifies the channel send timeout after which
+// the message is dropped.
+//
+// The default is 60 seconds.
+func WithChannelSendTimeout(d time.Duration) ChannelOption {
+ return func(c *channel) {
+ c.chanSendTimeout = d
+ }
+}
+
+type channel struct {
+ pubSub *PubSub
+
+ msgCh chan *Message
+ allCh chan interface{}
+ ping chan struct{}
+
+ chanSize int
+ chanSendTimeout time.Duration
+ checkInterval time.Duration
+}
+
+func newChannel(pubSub *PubSub, opts ...ChannelOption) *channel {
+ c := &channel{
+ pubSub: pubSub,
+
+ chanSize: 100,
+ chanSendTimeout: time.Minute,
+ checkInterval: 3 * time.Second,
+ }
+ for _, opt := range opts {
+ opt(c)
+ }
+ if c.checkInterval > 0 {
+ c.initHealthCheck()
+ }
+ return c
+}
+
+func (c *channel) initHealthCheck() {
+ ctx := context.TODO()
+ c.ping = make(chan struct{}, 1)
+
+ go func() {
+ timer := time.NewTimer(time.Minute)
+ timer.Stop()
+
+ for {
+ timer.Reset(c.checkInterval)
+ select {
+ case <-c.ping:
+ if !timer.Stop() {
+ <-timer.C
+ }
+ case <-timer.C:
+ if pingErr := c.pubSub.Ping(ctx); pingErr != nil {
+ c.pubSub.mu.Lock()
+ c.pubSub.reconnect(ctx, pingErr)
+ c.pubSub.mu.Unlock()
+ }
+ case <-c.pubSub.exit:
+ return
+ }
+ }
+ }()
+}
+
+// initMsgChan must be in sync with initAllChan.
+func (c *channel) initMsgChan() {
+ ctx := context.TODO()
+ c.msgCh = make(chan *Message, c.chanSize)
+
+ go func() {
+ timer := time.NewTimer(time.Minute)
+ timer.Stop()
+
+ var errCount int
+ for {
+ msg, err := c.pubSub.Receive(ctx)
+ if err != nil {
+ if err == pool.ErrClosed {
+ close(c.msgCh)
+ return
+ }
+ if errCount > 0 {
+ time.Sleep(100 * time.Millisecond)
+ }
+ errCount++
+ continue
+ }
+
+ errCount = 0
+
+ // Any message is as good as a ping.
+ select {
+ case c.ping <- struct{}{}:
+ default:
+ }
+
+ switch msg := msg.(type) {
+ case *Subscription:
+ // Ignore.
+ case *Pong:
+ // Ignore.
+ case *Message:
+ timer.Reset(c.chanSendTimeout)
+ select {
+ case c.msgCh <- msg:
+ if !timer.Stop() {
+ <-timer.C
+ }
+ case <-timer.C:
+ internal.Logger.Printf(
+ ctx, "redis: %s channel is full for %s (message is dropped)",
+ c, c.chanSendTimeout)
+ }
+ default:
+ internal.Logger.Printf(ctx, "redis: unknown message type: %T", msg)
+ }
+ }
+ }()
+}
+
+// initAllChan must be in sync with initMsgChan.
+func (c *channel) initAllChan() {
+ ctx := context.TODO()
+ c.allCh = make(chan interface{}, c.chanSize)
+
+ go func() {
+ timer := time.NewTimer(time.Minute)
+ timer.Stop()
+
+ var errCount int
+ for {
+ msg, err := c.pubSub.Receive(ctx)
+ if err != nil {
+ if err == pool.ErrClosed {
+ close(c.allCh)
+ return
+ }
+ if errCount > 0 {
+ time.Sleep(100 * time.Millisecond)
+ }
+ errCount++
+ continue
+ }
+
+ errCount = 0
+
+ // Any message is as good as a ping.
+ select {
+ case c.ping <- struct{}{}:
+ default:
+ }
+
+ switch msg := msg.(type) {
+ case *Pong:
+ // Ignore.
+ case *Subscription, *Message:
+ timer.Reset(c.chanSendTimeout)
+ select {
+ case c.allCh <- msg:
+ if !timer.Stop() {
+ <-timer.C
+ }
+ case <-timer.C:
+ internal.Logger.Printf(
+ ctx, "redis: %s channel is full for %s (message is dropped)",
+ c, c.chanSendTimeout)
+ }
+ default:
+ internal.Logger.Printf(ctx, "redis: unknown message type: %T", msg)
+ }
+ }
+ }()
+}