hubble observe does not work with stdin redirection

[bimmlerd]

Trying to avoid a useless use of cat I typed hubble observe < cilium-55s8v-hubble_observe.json, but was greeted with a cryptic failed to connect to 'localhost:4245': connection error: desc = "transport: error while dialing: dial tcp [::1]:4245: connect: connection refused". Typing cat cilium-55s8v-hubble_observe.json | hubble observe worked fine.

I'm guessing that the error stems from it trying and failing to connect to some cluster because tty detection (?) fails in this case. cc @gandro.

This happens both on zsh (5.8.1) and bash (5.2) on macOS Ventura 13.0 with hubble v0.10.0

[bimmlerd]

hubble/cmd/observe/flows.go

Lines 157 to 160 in a24aa4b

	if fi.Mode()&os.ModeNamedPipe != 0 {
	// read flows from stdin
	client = newIOReaderObserver(os.Stdin)
	logger.Logger.Debug("Reading flows from stdin")

looks like the culprit, I suspect input redirection is different from a FIFO pipe?

[gandro]

Reproducible on linux-amd64 (archlinux)

[rolinh]

I have a patch here, could you confirm that it works for you?

[bimmlerd]

Works for me, nice 🚀