blob: 242acf40e34a1730cb57c40e8c5f5487db08f392 (
plain) (
tree)
|
|
package slack
import (
"encoding/json"
"errors"
"sync"
"time"
"github.com/gorilla/websocket"
)
const (
// MaxMessageTextLength is the current maximum message length in number of characters as defined here
// https://api.slack.com/rtm#limits
MaxMessageTextLength = 4000
)
// RTM represents a managed websocket connection. It also supports
// all the methods of the `Client` type.
//
// Create this element with Client's NewRTM() or NewRTMWithOptions(*RTMOptions)
type RTM struct {
idGen IDGenerator
pingInterval time.Duration
pingDeadman *time.Timer
// Connection life-cycle
conn *websocket.Conn
IncomingEvents chan RTMEvent
outgoingMessages chan OutgoingMessage
killChannel chan bool
disconnected chan struct{} // disconnected is closed when Disconnect is invoked, regardless of connection state. Allows for ManagedConnection to not leak.
forcePing chan bool
rawEvents chan json.RawMessage
wasIntentional bool
isConnected bool
// Client is the main API, embedded
Client
websocketURL string
// UserDetails upon connection
info *Info
// useRTMStart should be set to true if you want to use
// rtm.start to connect to Slack, otherwise it will use
// rtm.connect
useRTMStart bool
// dialer is a gorilla/websocket Dialer. If nil, use the default
// Dialer.
dialer *websocket.Dialer
// mu is mutex used to prevent RTM connection race conditions
mu *sync.Mutex
}
// RTMOptions allows configuration of various options available for RTM messaging
//
// This structure will evolve in time so please make sure you are always using the
// named keys for every entry available as per Go 1 compatibility promise adding fields
// to this structure should not be considered a breaking change.
type RTMOptions struct {
// UseRTMStart set to true in order to use rtm.start or false to use rtm.connect
// As of 11th July 2017 you should prefer setting this to false, see:
// https://api.slack.com/changelog/2017-04-start-using-rtm-connect-and-stop-using-rtm-start
UseRTMStart bool
}
// Disconnect and wait, blocking until a successful disconnection.
func (rtm *RTM) Disconnect() error {
// avoid RTM disconnect race conditions
rtm.mu.Lock()
defer rtm.mu.Unlock()
// always push into the disconnected channel when invoked,
// this lets the ManagedConnection() function properly clean up.
// if the buffer is full then just continue on.
select {
case rtm.disconnected <- struct{}{}:
default:
}
if !rtm.isConnected {
return errors.New("Invalid call to Disconnect - Slack API is already disconnected")
}
rtm.killChannel <- true
return nil
}
// GetInfo returns the info structure received when calling
// "startrtm", holding all channels, groups and other metadata needed
// to implement a full chat client. It will be non-nil after a call to
// StartRTM().
func (rtm *RTM) GetInfo() *Info {
return rtm.info
}
// SendMessage submits a simple message through the websocket. For
// more complicated messages, use `rtm.PostMessage` with a complete
// struct describing your attachments and all.
func (rtm *RTM) SendMessage(msg *OutgoingMessage) {
if msg == nil {
rtm.Debugln("Error: Attempted to SendMessage(nil)")
return
}
rtm.outgoingMessages <- *msg
}
func (rtm *RTM) resetDeadman() {
timerReset(rtm.pingDeadman, deadmanDuration(rtm.pingInterval))
}
func deadmanDuration(d time.Duration) time.Duration {
return d * 4
}
|