Panic on enable user_subscribe_to_personal

[xjtdy888]

version: Centrifugo v2.8.3 (Go version: go1.16.2)
primary config:

   "proxy_connect_endpoint": "http://localhost:8000/api/cent/connect",
   "user_subscribe_to_personal" : true,
   "user_personal_channel_namespace": "personal",

  "namespaces": [
  	{
  		"name": "personal"
  	}

panic: assignment to entry in nil map

goroutine 53 [running]:
github.com/centrifugal/centrifugo/internal/client.(*Handler).OnClientConnecting(0xc000290240, 0x1b7b658, 0xc0000ac198, 0xc0001ac930, 0x24, 0x0, 0x0, 0x0, 0x0, 0x0, ...)
	/home/runner/work/centrifugo/centrifugo/internal/client/handler.go:295 +0x34b
github.com/centrifugal/centrifugo/internal/client.(*Handler).Setup.func1(0x1b7b658, 0xc0000ac198, 0xc0001ac930, 0x24, 0x0, 0x0, 0x0, 0x0, 0x0, 0xc0004cc3d8, ...)
	/home/runner/work/centrifugo/centrifugo/internal/client/handler.go:82 +0xeb
github.com/centrifugal/centrifuge.(*Client).connectCmd(0xc0002be000, 0xc00008c140, 0xc0004d4078, 0x0, 0x0)
	/home/runner/go/pkg/mod/github.com/centrifugal/centrifuge@v0.14.2/client.go:1596 +0x1ad8
github.com/centrifugal/centrifuge.(*Client).handleConnect(0xc0002be000, 0xc0004cc100, 0xd, 0x10, 0xc0004d4078, 0x0, 0x19b4b60)
	/home/runner/go/pkg/mod/github.com/centrifugal/centrifuge@v0.14.2/client.go:929 +0x1e5
github.com/centrifugal/centrifuge.(*Client).handleCommand(0xc0002be000, 0xc0004ca000, 0x0)
	/home/runner/go/pkg/mod/github.com/centrifugal/centrifuge@v0.14.2/client.go:812 +0x519
github.com/centrifugal/centrifuge.(*Client).Handle(0xc0002be000, 0xc0004c6000, 0x1f, 0x200, 0x200)
	/home/runner/go/pkg/mod/github.com/centrifugal/centrifuge@v0.14.2/client.go:721 +0x411
github.com/centrifugal/centrifuge.(*WebsocketHandler).ServeHTTP.func2(0x5d21dba00, 0x3b9aca00, 0x0, 0x1a14653, 0x4, 0x1a14653, 0x4, 0xc0001cc000, 0xc0000bfb00, 0xc000090400)
	/home/runner/go/pkg/mod/github.com/centrifugal/centrifuge@v0.14.2/handler_websocket.go:343 +0x559
created by github.com/centrifugal/centrifuge.(*WebsocketHandler).ServeHTTP
	/home/runner/go/pkg/mod/github.com/centrifugal/centrifuge@v0.14.2/handler_websocket.go:304 +0x2a5

[xjtdy888]

It looks like

centrifugo/internal/client/handler.go

Line 272 in dab3bc9

subscriptions = connectReply.Subscriptions

This overwrites the previously initialized variable and becomes nil if the endpoint does not return channel information

[FZambia]

@xjtdy888 hello, thanks for finding and fixing! Let's keep this open till release.

[FZambia]

v2.8.4 with #437 released