This fixes golint failures of the following file:
- test/e2e/framework/volume_util.go
This changes following file because of change function name
in above file.
- test/e2e/storage/testsuites/volumes.go
Need to add bracket in the tag for sig-windows. Also fix an issue: for
current testing structure, it first init driver and then set up the
framework. So when initialize the driver, it does not know what OS is
and we can not set up the capabilities correctly. Instead we have to add
all the capabilities and supported fs types including both linux and
windows. Later in the code, we will check the Node OS and decide how to
run the test.
It is useful to apply the storage testsuite also to "external" (=
out-of-tree) storage drivers. One way of doing that is setting up a
custom E2E test suite, but that's still quite a bit of work.
An easier alternative is to parameterize the Kubernetes e2e.test
binary at runtime so that it instantiates the testsuite for one or
more drivers. Some parameters have to be provided before starting the
test because they define configuration and capabilities of the driver
and its storage backend that cannot be discovered at runtime. This is
done by populating the DriverDefinition with the content of the file
that the new -storage.testdriver parameters points to.
The universal .yaml and .json decoder from Kubernetes is used. It's
flexible, but has some downsides:
- currently ignores unknown fields (see https://github.com/kubernetes/kubernetes/pull/71589)
- poor error messages when fields have the wrong type
Storage drivers have to be installed in the test cluster before
starting e2e.test. Only tests involving dynamically provisioned
volumes are currently supported.
There is a risk that the init function does not reset one of the local
variables that was set by a previous test. To avoid this, all
variables set by init are now in a struct which gets cleaned
completely first.
The recommended approach for not running unsuitable tests is to skip
them at runtime with an explanation. Filtering out unsuitable test
patters and thus not even defining unsuitable tests was done earlier
because it was faster than skipping tests at runtime.
But now these tests can be skipped efficiently, so this special case
can be removed.
CreateDriver (now called SetupTest) is a potentially expensive
operation, depending on the driver. Creating and tearing down a
framework instance also takes time (measured at 6 seconds on a fast
machine) and produces quite a bit of log output.
Both can be avoided for tests that skip based on static
information (like for instance the current OS, vendor, driver and test
pattern) by making the test suite responsible for creating framework
and driver.
The lifecycle of the TestConfig instance was confusing because it was
stored inside the DriverInfo, a struct which conceptually is static,
while the TestConfig is dynamic. It is cleaner to separate the two,
even if that means that an additional pointer must be passed into some
functions. Now CreateDriver is responsible for initializing the
PerTestConfig that is to be used by the test.
To make this approach simpler to implement (= less functions which
need the pointer) and the tests easier to read, the entire setup and
test definition is now contained in a single function. This is how it
is normally done in Ginkgo. This is easier to read because one can see
at a glance where variables are set, instead of having to trace values
though two additional structs (TestResource and TestInput).
Because we are changing the API already, also other changes are made:
- some function prototypes get simplified
- the naming of functions is changed to match their purpose
(tests aren't executed by the test suite, they only get defined
for later execution)
- unused methods get removed (TestSuite.skipUnsupportedTest is redundant)
This increases type safety and makes the code easier to read because
it becomes obvious that the "test resource" passed to some functions
must be the result of a previous CreateVolume.
This makes it possible to remove:
- functions that never did anything (the DeleteVolume methods in
drivers that never create a volume)
- type casts (in the DeleteVolume implementation)
- the unused DeleteVolume parameters
- the stand-alone DeleteVolume function (which would be just a non-nil
check)
GetPersistentVolumeSource and GetVolumeSource could also become
methods on more specific interfaces - they don't actually use anything
from TestDriver instance which provides them.
The main motivation however is to reduce the number of methods which
might need an explicit test config parameter.
Whether the read test after writing was done on the same node was
random for drivers that weren't locked onto a single node. Now it is
deterministic: it always happens on the same node.
The case with reading on another node is covered separately for test
configurations that support it (not locked onto a single node, more
than one node in the test cluster).
As before, the TestConfig.ClientNodeSelector is ignored by the
provisioning testsuite.
TestDynamicProvisioning had multiple ways of choosing additional
checks:
- the PvCheck callback
- the builtin write/read check controlled by a boolean
- the snapshot testing
Complicating matters further, that builtin write/read test had been
more customizable with new fields `NodeSelector` and
`ExpectUnschedulable` which were only set by one particular test (see
https://github.com/kubernetes/kubernetes/pull/70941).
That is confusing and will only get more confusing when adding more
checks in the future. Therefore the write/read check is now a separate
function that must be enabled explicitly by tests that want to run it.
The snapshot checking is also defined only for the snapshot test.
The test that expects unschedulable pods now also checks for that
particular situation itself. Instead of testing it with two pods (the
behavior from the write/read check) that both fail to start, only a
single unschedulable pod is created.
Because node name, node selector and the `ExpectUnschedulable` were
only used for checking, it is possible to simplify `StorageClassTest`
by removing all of these fields.
Expect(err).NotTo(HaveOccurred()) is an anti-pattern in Ginkgo testing
because a test failure doesn't explain what failed (see
https://github.com/kubernetes/kubernetes/issues/34059). We avoid it
now by making the check function itself responsible for checking
errors and including more information in those checks.
When the provisioning test gets stuck, the log fills up with messages
about waiting for a certain pod to run. Now the pod names are
pvc-[volume-tester|snapshot]-[writer|reader] plus the random
number appended by Kubernetes. This makes it easier to see where the
test is stuck.
There is no need to check for empty strings, we can also directly
initialize structs with the value. The end result is the same when the
value is empty (empty string in the struct).
This addresses the two remaining change requests from
https://github.com/kubernetes/kubernetes/pull/69036:
- replace "csi-hostpath-v0" name check with capability
check (cleaner that way)
- add feature tag to "should create snapshot with defaults" because
that is an alpha feature
Signed-off-by: Patrick Ohly <patrick.ohly@intel.com>
Even if snapshots are supported by the driver interface, the driver or
suite might still want to skip a particular test, so those checks
still need to be executed.
Exposing framework.VolumeTestConfig as part of the testsuite package
API was confusing because it was unclear which of the values in it
really have an effect. How it was set also was a bit awkward: a test
driver had a copy that had to be overwritten at test runtime and then
might have been updated and/or overwritten again by the driver.
Now testsuites has its own test config structure. It contains the
values that might have to be set dynamically at runtime. Instead of
overwriting a copy of that struct inside the test driver, the test
driver takes some common defaults (specifically, the framework pointer
and the prefix) when it gets initialized and then manages its own
copy. For example, the hostpath driver has to lock the pods to a
single node.
framework.VolumeTestConfig is still used internally and test drivers
can decide to run tests with a fully populated instance if needed (for
example, after setting up an NFS server).
This makes it possible to use the testsuites package out-of-tree
without pulling in unnecessary dependencies and code (in
test/e2e/storage/vsphere) that defines tests that are not wanted in a
custom test suite.
Different drivers support different volume sizes. Some have certain
minimum sizes, some maximum sizes. Instead of hard-coding some kind of
default into the testsuites, now each driver that supports dynamic
provisioning has to provide the size.
