tile38/pkg/controller/pubsub.go

364 lines
8.0 KiB
Go

package controller
import (
"io"
"net"
"strconv"
"sync"
"time"
"github.com/tidwall/gjson"
"github.com/tidwall/match"
"github.com/tidwall/redcon"
"github.com/tidwall/resp"
"github.com/tidwall/tile38/pkg/log"
"github.com/tidwall/tile38/pkg/server"
)
const (
pubsubChannel = iota
pubsubPattern
)
type pubsub struct {
mu sync.RWMutex
hubs [2]map[string]*subhub
}
func newPubsub() *pubsub {
return &pubsub{
hubs: [2]map[string]*subhub{
make(map[string]*subhub),
make(map[string]*subhub),
},
}
}
// Publish a message to subscribers
func (c *Controller) Publish(channel string, message ...string) int {
var msgs []submsg
c.pubsub.mu.RLock()
if hub := c.pubsub.hubs[pubsubChannel][channel]; hub != nil {
for target := range hub.targets {
for _, message := range message {
msgs = append(msgs, submsg{
kind: pubsubChannel,
target: target,
channel: channel,
message: message,
})
}
}
}
for pattern, hub := range c.pubsub.hubs[pubsubPattern] {
if match.Match(channel, pattern) {
for target := range hub.targets {
for _, message := range message {
msgs = append(msgs, submsg{
kind: pubsubPattern,
target: target,
channel: channel,
pattern: pattern,
message: message,
})
}
}
}
}
c.pubsub.mu.RUnlock()
for _, msg := range msgs {
msg.target.cond.L.Lock()
msg.target.msgs = append(msg.target.msgs, msg)
msg.target.cond.Broadcast()
msg.target.cond.L.Unlock()
}
return len(msgs)
}
func (ps *pubsub) register(kind int, channel string, target *subtarget) {
ps.mu.Lock()
hub, ok := ps.hubs[kind][channel]
if !ok {
hub = newSubhub()
ps.hubs[kind][channel] = hub
}
hub.targets[target] = true
ps.mu.Unlock()
}
func (ps *pubsub) unregister(kind int, channel string, target *subtarget) {
ps.mu.Lock()
hub, ok := ps.hubs[kind][channel]
if ok {
delete(hub.targets, target)
if len(hub.targets) == 0 {
delete(ps.hubs[kind], channel)
}
}
ps.mu.Unlock()
}
type submsg struct {
kind byte
target *subtarget
pattern string
channel string
message string
}
type subtarget struct {
cond *sync.Cond
msgs []submsg
closed bool
}
func newSubtarget() *subtarget {
target := new(subtarget)
target.cond = sync.NewCond(&sync.Mutex{})
return target
}
type subhub struct {
targets map[*subtarget]bool
}
func newSubhub() *subhub {
hub := new(subhub)
hub.targets = make(map[*subtarget]bool)
return hub
}
type liveSubscriptionSwitches struct {
// no fields. everything is managed through the server.Message
}
func (sub liveSubscriptionSwitches) Error() string {
return goingLive
}
func (c *Controller) cmdSubscribe(msg *server.Message) (resp.Value, error) {
if len(msg.Values) < 2 {
return resp.Value{}, errInvalidNumberOfArguments
}
return server.NOMessage, liveSubscriptionSwitches{}
}
func (c *Controller) cmdPsubscribe(msg *server.Message) (resp.Value, error) {
if len(msg.Values) < 2 {
return resp.Value{}, errInvalidNumberOfArguments
}
return server.NOMessage, liveSubscriptionSwitches{}
}
func (c *Controller) cmdPublish(msg *server.Message) (resp.Value, error) {
start := time.Now()
if len(msg.Values) != 3 {
return resp.Value{}, errInvalidNumberOfArguments
}
channel := msg.Values[1].String()
message := msg.Values[2].String()
//geofence := gjson.Valid(message) && gjson.Get(message, "fence").Bool()
n := c.Publish(channel, message) //, geofence)
var res resp.Value
switch msg.OutputType {
case server.JSON:
res = resp.StringValue(`{"ok":true` +
`,"published":` + strconv.FormatInt(int64(n), 10) +
`,"elapsed":"` + time.Now().Sub(start).String() + `"}`)
case server.RESP:
res = resp.IntegerValue(n)
}
return res, nil
}
func (c *Controller) liveSubscription(
conn net.Conn,
rd *server.PipelineReader,
msg *server.Message,
websocket bool,
) error {
defer conn.Close() // close connection when we are done
outputType := msg.OutputType
connType := msg.ConnType
if websocket {
outputType = server.JSON
}
var start time.Time
// write helpers
var writeLock sync.Mutex
write := func(data []byte) {
writeLock.Lock()
defer writeLock.Unlock()
writeLiveMessage(conn, data, false, connType, websocket)
}
writeOK := func() {
switch outputType {
case server.JSON:
write([]byte(`{"ok":true` +
`,"elapsed":"` + time.Now().Sub(start).String() + `"}`))
case server.RESP:
write([]byte(`+OK\r\n`))
}
}
writeWrongNumberOfArgsErr := func(command string) {
switch outputType {
case server.JSON:
write([]byte(`{"ok":false,"err":"invalid number of arguments"` +
`,"elapsed":"` + time.Now().Sub(start).String() + `"}`))
case server.RESP:
write([]byte(`-ERR wrong number of arguments ` +
`for '` + command + `' command\r\n`))
}
}
writeOnlyPubsubErr := func() {
switch outputType {
case server.JSON:
write([]byte(`{"ok":false` +
`,"err":"only (P)SUBSCRIBE / (P)UNSUBSCRIBE / ` +
`PING / QUIT allowed in this context"` +
`,"elapsed":"` + time.Now().Sub(start).String() + `"}`))
case server.RESP:
write([]byte("-ERR only (P)SUBSCRIBE / (P)UNSUBSCRIBE / " +
"PING / QUIT allowed in this context\r\n"))
}
}
writeSubscribe := func(command, channel string, num int) {
switch outputType {
case server.JSON:
write([]byte(`{"ok":true` +
`,"command":` + jsonString(command) +
`,"channel":` + jsonString(channel) +
`,"num":` + strconv.FormatInt(int64(num), 10) +
`,"elapsed":"` + time.Now().Sub(start).String() + `"}`))
case server.RESP:
b := redcon.AppendArray(nil, 3)
b = redcon.AppendBulkString(b, command)
b = redcon.AppendBulkString(b, channel)
b = redcon.AppendInt(b, int64(num))
write(b)
}
}
writeMessage := func(msg submsg) {
if msg.kind == pubsubChannel {
switch outputType {
case server.JSON:
var data []byte
if !gjson.Valid(msg.message) {
data = appendJSONString(nil, msg.message)
} else {
data = []byte(msg.message)
}
write(data)
case server.RESP:
b := redcon.AppendArray(nil, 3)
b = redcon.AppendBulkString(b, "message")
b = redcon.AppendBulkString(b, msg.channel)
b = redcon.AppendBulkString(b, msg.message)
write(b)
}
} else {
switch outputType {
case server.JSON:
var data []byte
if !gjson.Valid(msg.message) {
data = appendJSONString(nil, msg.message)
} else {
data = []byte(msg.message)
}
write(data)
case server.RESP:
b := redcon.AppendArray(nil, 4)
b = redcon.AppendBulkString(b, "pmessage")
b = redcon.AppendBulkString(b, msg.pattern)
b = redcon.AppendBulkString(b, msg.channel)
b = redcon.AppendBulkString(b, msg.message)
write(b)
}
}
}
m := [2]map[string]bool{
make(map[string]bool),
make(map[string]bool),
}
target := newSubtarget()
defer func() {
for i := 0; i < 2; i++ {
for channel := range m[i] {
c.pubsub.unregister(i, channel, target)
}
}
target.cond.L.Lock()
target.closed = true
target.cond.Broadcast()
target.cond.L.Unlock()
}()
go func() {
log.Debugf("pubsub open")
defer log.Debugf("pubsub closed")
for {
var msgs []submsg
target.cond.L.Lock()
if len(target.msgs) > 0 {
msgs = target.msgs
target.msgs = nil
}
target.cond.L.Unlock()
for _, msg := range msgs {
writeMessage(msg)
}
target.cond.L.Lock()
if target.closed {
target.cond.L.Unlock()
return
}
target.cond.Wait()
target.cond.L.Unlock()
}
}()
msgs := []*server.Message{msg}
for {
for _, msg := range msgs {
start = time.Now()
var kind int
switch msg.Command {
case "quit":
writeOK()
return nil
case "psubscribe":
kind = pubsubPattern
case "subscribe":
kind = pubsubChannel
default:
writeOnlyPubsubErr()
}
if len(msg.Values) < 2 {
writeWrongNumberOfArgsErr(msg.Command)
}
for i := 1; i < len(msg.Values); i++ {
channel := msg.Values[i].String()
m[kind][channel] = true
c.pubsub.register(kind, channel, target)
writeSubscribe(msg.Command, channel, len(m[0])+len(m[1]))
}
}
var err error
msgs, err = rd.ReadMessages()
if err != nil {
if err == io.EOF {
return nil
}
return err
}
}
}