Consul doesn't understand ExposedPort JSON field sent by ESM

[Riscky]

When running Consul ESM v0.6.2 together with Consul v1.10.4, the following warning is logged:

{
  "@level": "warn",
  "@message": "Error updating check status in Consul",
  "@module": "consul-esm",
  "@timestamp": "2022-11-18T12:45:58.035983+01:00",
  "error": "Failed request: Failed to parse body: json: unknown field \"ExposedPort\""
}

when trying to register a health status change.

Although this is logged as a warning, this actually means that ESM does not register health status changes at all.

I tried debugging this a bit, and as far as I understand the code, the inner error (Failed to parse body: json: unknown field \"ExposedPort\") is thrown by Consul (not ESM).
The release notes of Consul v1.10.0 lists the addition of the ExposedPort to the healthcheck API though.

ESM v0.6.x might just not be compatible with Consul v1.10.x and lower, in which case that should be added to the compatibility table in the readme.

I also think the warning should be promoted to an error, because registering health status changes is the primary function of ESM.

[ulidtko]

Beyond the docs, please also update version.go:

consul-esm/version/version.go

Lines 14 to 16 in b986a4e

	// consulVersionConstraint is the compatible version constraint
	// between ESM with Consul.
	const consulVersionConstraint = ">= 1.4.1"