EmitSync stuck in channel

[rockwithamoon]

Hello.

I've noticed on rare occasions that EmitSync() does not return. From the stack trace it seems that done channel is not closing from https://github.com/lovoo/goka/blob/v1.1.1/emitter.go#L114

goroutine 6730623 [chan receive, 41 minutes]:
github.com/lovoo/goka.(*Emitter).EmitSyncWithHeaders(0xc08e5da290, {0xc042657368, 0x14}, {0x102b720, 0xc05475da40}, 0x1299ce0)
        /go/src/bitbucket.org/xx/xx/vendor/github.com/lovoo/goka/emitter.go:114 +0x131
github.com/lovoo/goka.(*Emitter).EmitSync(...)
        /go/src/bitbucket.org/xx/xx/vendor/github.com/lovoo/goka/emitter.go:120
bitbucket.org/xx/xx/core/ke.(*Kafka).mainLoop.func1({{0xc042657368, 0xc05ecc4fd0}, 0xc05475da40, 0xc070ce5500})
        /go/src/bitbucket.org/xx/xx/core/ke/ke.go:74 +0x4b
created by bitbucket.org/xx/xx/core/ke.(*Kafka).mainLoop
        /go/src/bitbucket.org/xx/xx/core/ke/ke.go:73 +0x7d

It's an older version of goka, I'll upgrade to latest but this happens once a month or so it will take a while for feedback.

        github.com/lovoo/goka v1.1.1
        github.com/Shopify/sarama v1.31.0 // indirect

[frairon]

Hmm, that looks really strange. The logic inside the emitter is not that complicated. It's merely wrapping sarama. Does the error occur during shutdown of the emitter or at normal runtime?

[rockwithamoon]

This is during normal runtime. I'm not 100% sure yet if this happens during Kafka re-partitioning. I've updated to goka v1.1.7 and sarama v1.38.1. If it occurs again I'll try to debug more as I've seen some receiving channels in waiting in sarama/async_producer.go.

[rockwithamoon]

After upgrading to sarama v1.38.1 this behaviour isn't reproduced. I'm closing this. Thanks.