Description
esl is a go library to connect to freeSWITCH via esl.
Installation
Installation can be done as usual:
$ go get github.com/vma/esl
How it works
esl.NewConnection create a new esl connection and take a ConnectionHandler interface
which defines the callbacks to handle the esl events.
Example of use
This simple example originate a call, park it and start music on hold when it is answered.
When the call is hanged up, we close the connection, which ends the con.HandleEvents() loop.
package main
import (
"fmt"
"log"
"github.com/vma/esl"
)
type Handler struct {
CallId string
BgJobId string
}
const (
Caller = "+33184850000"
Callee = "+33184850001"
)
func main() {
handler := &Handler{}
con, err := esl.NewConnection("127.0.0.1:8021", handler)
if err != nil {
log.Fatal("ERR connecting to freeswitch:", err)
}
con.HandleEvents()
}
func (h *Handler) OnConnect(con *esl.Connection) {
con.SendRecv("event", "plain", "ALL")
h.CallId, _ = con.Api("create_uuid")
log.Println("call id:", h.CallId)
h.BgJobId, _ = con.BgApi("originate", "{origination_uuid="+h.CallId+
",origination_caller_id_number="+Caller+"}sofia/gateway/provider/"+Callee, "&park()")
log.Println("originate bg job id:", h.BgJobId)
}
func (h *Handler) OnDisconnect(con *esl.Connection, ev *esl.Event) {
log.Println("esl disconnected:", ev)
}
func (h *Handler) OnClose(con *esl.Connection) {
log.Println("esl connection closed")
}
func (h *Handler) OnEvent(con *esl.Connection, ev *esl.Event) {
log.Printf("%s - event %s %s %s\n", ev.UId, ev.Name, ev.App, ev.AppData)
fmt.Println(ev) // send to stderr as it is very verbose
switch ev.Name {
case esl.BACKGROUND_JOB:
log.Printf("bg job result:%s\n", ev.GetTextBody())
case esl.CHANNEL_ANSWER:
log.Println("call answered, starting moh")
con.Execute("playback", h.CallId, "local_stream://moh")
case esl.CHANNEL_HANGUP:
hupcause := ev.Get("Hangup-Cause")
log.Printf("call terminated with cause %s", hupcause)
con.Close()
}
}TODO
- add documentation
- add tests
- more usage examples