Use OnOpen handler for DataChannels

Using an improvment of pion/datachannel, the channel opener can now
set an event to be called when the DATA_CHANNEL_ACK message is recieved

Resolves pion#1063
Relates to pion/datachannel#81

datachannel.go

@@ -169,7 +169,7 @@ func (d *DataChannel) open(sctpTransport *SCTPTransport) error {
 	dc.OnBufferedAmountLow(d.onBufferedAmountLow)
 	d.mu.Unlock()
 
-	d.handleOpen(dc)
+	d.handleOpen(dc, false)
 	return nil
 }
 
@@ -263,13 +263,22 @@ func (d *DataChannel) onMessage(msg DataChannelMessage) {
 	handler(msg)
 }
 
-func (d *DataChannel) handleOpen(dc *datachannel.DataChannel) {
+func (d *DataChannel) handleOpen(dc *datachannel.DataChannel, isRemote bool) {
 	d.mu.Lock()
 	d.dataChannel = dc
 	d.mu.Unlock()
 	d.setReadyState(DataChannelStateOpen)
 
-	d.onOpen()
+	// Fire the OnOpen handler immediately not using pion/datachannel
+	// * detached datachannels have no read loop, the user needs to read and query themselves
+	// * remote datachannels should fire OnOpened. This isn't spec compliant, but we can't break behavior yet
+	if d.api.settingEngine.detach.DataChannels || isRemote {
+		d.onOpen()
+	} else {
+		dc.OnOpen(func() {
+			d.onOpen()
+		})
+	}
 
 	d.mu.Lock()
 	defer d.mu.Unlock()

go.mod

@@ -5,7 +5,7 @@ go 1.13
 require (
 	github.com/onsi/ginkgo v1.16.1 // indirect
 	github.com/onsi/gomega v1.11.0 // indirect
-	github.com/pion/datachannel v1.4.21
+	github.com/pion/datachannel v1.5.0
 	github.com/pion/dtls/v2 v2.0.10
 	github.com/pion/ice/v2 v2.1.13
 	github.com/pion/interceptor v0.1.0

go.sum

@@ -37,8 +37,8 @@ github.com/onsi/gomega v1.7.1/go.mod h1:XdKZgCCFLUoM/7CFJVPcG8C1xQ1AJ0vpAezJrB7J
 github.com/onsi/gomega v1.10.1/go.mod h1:iN09h71vgCQne3DLsj+A5owkum+a2tYe+TOCB1ybHNo=
 github.com/onsi/gomega v1.11.0 h1:+CqWgvj0OZycCaqclBD1pxKHAU+tOkHmQIWvDHq2aug=
 github.com/onsi/gomega v1.11.0/go.mod h1:azGKhqFUon9Vuj0YmTfLSmx0FUwqXYSTl5re8lQLTUg=
-github.com/pion/datachannel v1.4.21 h1:3ZvhNyfmxsAqltQrApLPQMhSFNA+aT87RqyCq4OXmf0=
-github.com/pion/datachannel v1.4.21/go.mod h1:oiNyP4gHx2DIwRzX/MFyH0Rz/Gz05OgBlayAI2hAWjg=
+github.com/pion/datachannel v1.5.0 h1:Jy6xWr9hysxet69qP23ibiJ6M0P30ZRnndHU+N6cpkY=
+github.com/pion/datachannel v1.5.0/go.mod h1:TVbgWP+PVM9TlwL1IkG3JqXXfjGxLvsu9QUeFdpTegI=
 github.com/pion/dtls/v2 v2.0.9/go.mod h1:O0Wr7si/Zj5/EBFlDzDd6UtVxx25CE1r7XM7BQKYQho=
 github.com/pion/dtls/v2 v2.0.10 h1:wgys7gPR1NMbWjmjJ3CW7lkUGaun8djgH8nahpNLnxI=
 github.com/pion/dtls/v2 v2.0.10/go.mod h1:00OxfeCRWHShcqT9jx8pKKmBWuTt0NCZoVPCaC4VKvU=
@@ -59,7 +59,6 @@ github.com/pion/rtp v1.7.0/go.mod h1:bDb5n+BFZxXx0Ea7E5qe+klMuqiBrP+w8XSjiWtCUko
 github.com/pion/rtp v1.7.2/go.mod h1:bDb5n+BFZxXx0Ea7E5qe+klMuqiBrP+w8XSjiWtCUko=
 github.com/pion/rtp v1.7.4 h1:4dMbjb1SuynU5OpA3kz1zHK+u+eOCQjW3MAeVHf1ODA=
 github.com/pion/rtp v1.7.4/go.mod h1:bDb5n+BFZxXx0Ea7E5qe+klMuqiBrP+w8XSjiWtCUko=
-github.com/pion/sctp v1.7.10/go.mod h1:EhpTUQu1/lcK3xI+eriS6/96fWetHGCvBi9MSsnaBN0=
 github.com/pion/sctp v1.7.12 h1:GsatLufywVruXbZZT1CKg+Jr8ZTkwiPnmUC/oO9+uuY=
 github.com/pion/sctp v1.7.12/go.mod h1:xFe9cLMZ5Vj6eOzpyiKjT9SwGM4KpK/8Jbw5//jc+0s=
 github.com/pion/sdp/v3 v3.0.4 h1:2Kf+dgrzJflNCSw3TV5v2VLeI0s/qkzy2r5jlR0wzf8=
@@ -76,8 +75,6 @@ github.com/pion/turn/v2 v2.0.5 h1:iwMHqDfPEDEOFzwWKT56eFmh6DYC6o/+xnLAEzgISbA=
 github.com/pion/turn/v2 v2.0.5/go.mod h1:APg43CFyt/14Uy7heYUOGWdkem/Wu4PhCO/bjyrTqMw=
 github.com/pion/udp v0.1.1 h1:8UAPvyqmsxK8oOjloDk4wUt63TzFe9WEJkg5lChlj7o=
 github.com/pion/udp v0.1.1/go.mod h1:6AFo+CMdKQm7UiA0eUPA8/eVCTx8jBIITLZHc9DWX5M=
-github.com/pkg/errors v0.9.1 h1:FEBLx1zS214owpjy7qsBeixbURkuhQAwrK5UwLGTwt4=
-github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/sclevine/agouti v3.0.0+incompatible h1:8IBJS6PWz3uTlMP3YBIR5f+KAldcGuOeFkFbUWfBgK4=

sctptransport.go

@@ -195,7 +195,7 @@ func (r *SCTPTransport) acceptDataChannels(a *sctp.Association) {
 		}
 
 		<-r.onDataChannel(rtcDC)
-		rtcDC.handleOpen(dc)
+		rtcDC.handleOpen(dc, true)
 
 		r.lock.Lock()
 		r.dataChannelsOpened++