The io/ioutil package has been deprecated as of Go 1.16, see
https://golang.org/doc/go1.16#ioutil. This commit replaces the existing
io/ioutil functions with their new definitions in io and os packages.
Signed-off-by: Eng Zer Jun <engzerjun@gmail.com>
kube-apiserver doesn't expose the healthcheck via a dedicated
endpoint, instead relying on anonyomous-access being enabled. That
has previously forced us to enable the unauthenticated endpoint on
127.0.0.1:8080.
Instead we now run a small sidecar container, which
proxies /healthz and /readyz requests (only) adding appropriate
authentication using a client certificate.
This will also enable better load balancer checks in future, as these
have previously been hampered by the custom CA certificate.
Co-authored-by: John Gardiner Myers <jgmyers@proofpoint.com>