Implement an end-to-end test with all feature sources enabled. The new
test runs nfd-worker as a daemonset on all (schedulable) nodes of the
test cluster which makes it possible to cover a wide range features,
assuming the test cluster is heterogenous containing nodes with varying
system configurations.
The features available depends on the node(s) the e2e testa are run on.
Thus, some runtime parameterization of the tests is needed. The patch
adds a new command line test flag 'nfd.e2e-config' that is used to
specify the per-node feature labels and annotations that is expected to
be present in the cluster. An example configuration file is provided
with the patch. The pod spec of nfd-worker deployment is changed to
better correspond the default deployment and thus enable wider feature
discovery. This means using hostnetwork and adding mounts for /sys /boot
and /etc/os-release.
The patch changes node object management so that all nfd-related labels
are removed after each test (not just the ones the test is expected to
add). Also, all nfd-related annotations are now removed.
Tests that nfd master-worker communication works and that the worker is
able to label the node with the labels from the 'fake' source.
An example of running the test suite with a custom image with user's
kubeconfig:
$ go test ./test/e2e/ -args -nfd.repo=<image-repo> -nfd.tag=<image-tag> \
-kubeconfig=$HOME/.kube/config
Partly based on some previous work done by Balaji Subramaniam.
Patch the (Kubernetes) e2e wireframe introduced in the previous commit with some minor
modifications, dropping some bits in order to simplify the code.
Also adds a dummy test stub for node feature discovery.
Also, adds new method WaitForReady() into NfdMaster.
In practice, this quite widely tests nfd-master, too, as the tests
create an instance of NfdMaster and verify that the communication
between master and worker works.
