Simple Go microservice which returns a host info string (name and IP of the host). Accessible via curl, wget, etc.
Listens on port 9898 by default, if an int is passed on the command line, that port is used instead. Particularly
useful when demonstrating K8s service routing operation (deploy several replicas of this, create a service for the
set, then curl the service sequentially to see various hosts respond). The hostinfo service logs inbound requests
and the client IP to stdout.
/pythoncontains a Python version of the service/otelcontains a Go version of the service that logs in Open Telemetry format
$ ./hostinfo # listening on port 9898
$ ./hostinfo 80 # listening on port 80
To curl the default port locally:
$ curl localhost:9898
Ming-The-Merciless 192.168.131.12
To wget an instance running on port 80 via a given IP address:
$ wget -O - 10.90.11.43
Doctor-Zarko 10.90.11.43
To curl a k8s service backed by hostinfo instances:
$ kubectl run planetmongo --image rxmllc/hostinfo --port 9898
$ kubectl expose pod planetmongo --port 80 --target-port 9898
Now from another pod:
$ kubectl run -it --rm client rxmllc/tools
$ curl planetmongo.default.svc.cluster.local
planetmongo 10.90.11.42