consul/connect: ingress gateway w/ host networking and absent proxy will NPE client

[shoenig]

When submitting a job with an ingress gateway in host networking mode and no proxy block, the client will NPE.

With bridge networking we inject a proxy block avoiding the condition.

Immediate workaround: add an empty proxy { } block.

# network.mode = "host"

connect {
  gateway {

    # without this block, client will NPE
    # on ingress gateways using host networking
    # proxy {}

    ingress {}
  }
}

==> Newer Nomad version available: 1.0.1 (currently running: 1.0.0-dev)
panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x10 pc=0x1551b8e]

goroutine 854 [running]:
github.com/hashicorp/nomad/command/agent/consul.newConnectGateway(0xc000f06220, 0x12, 0xc000866260, 0xc0005ee228)
	/home/shoenig/go/src/github.com/hashicorp/nomad/command/agent/consul/connect.go:52 +0x6e
github.com/hashicorp/nomad/command/agent/consul.(*ServiceClient).serviceRegs(0xc000490000, 0xc000f4a0c0, 0xc000e3a000, 0xc000e3a160, 0x3099d20, 0xc000866220, 0xbabcd8)

The broken line

Best fix is probably to just Canonicalize in a default empty proxy - it gets tweaked by Nomad down the line regardless.

[github-actions]

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