Issue [0] reports an error when a pod associated to a `StatefulSet`
whose IPPool is already full is deleted. According to it, the new pod -
scheduled by the `StatefulSet` - cannot run because the IPPool is
already full, and the old pod's IP cannot be garbage collected because
we match by pod reference - and the "new" pod is stuck in `creating`
phase.

[0] - k8snetworkplumbingwg#182

Signed-off-by: Miguel Duarte Barroso <[email protected]>

Issue [0] reports an error when a pod associated to a `StatefulSet`
whose IPPool is already full is deleted. According to it, the new pod -
scheduled by the `StatefulSet` - cannot run because the IPPool is
already full, and the old pod's IP cannot be garbage collected because
we match by pod reference - and the "new" pod is stuck in `creating`
phase.

[0] - k8snetworkplumbingwg#182

Signed-off-by: Miguel Duarte Barroso <[email protected]>

Issue [0] reports an error when a pod associated to a `StatefulSet`
whose IPPool is already full is deleted. According to it, the new pod -
scheduled by the `StatefulSet` - cannot run because the IPPool is
already full, and the old pod's IP cannot be garbage collected because
we match by pod reference - and the "new" pod is stuck in `creating`
phase.

[0] - k8snetworkplumbingwg#182

Signed-off-by: Miguel Duarte Barroso <[email protected]>

Issue [0] reports an error when a pod associated to a `StatefulSet`
whose IPPool is already full is deleted. According to it, the new pod -
scheduled by the `StatefulSet` - cannot run because the IPPool is
already full, and the old pod's IP cannot be garbage collected because
we match by pod reference - and the "new" pod is stuck in `creating`
phase.

[0] - k8snetworkplumbingwg#182

Signed-off-by: Miguel Duarte Barroso <[email protected]>

Issue [0] reports an error when a pod associated to a `StatefulSet`
whose IPPool is already full is deleted. According to it, the new pod -
scheduled by the `StatefulSet` - cannot run because the IPPool is
already full, and the old pod's IP cannot be garbage collected because
we match by pod reference - and the "new" pod is stuck in `creating`
phase.

[0] - k8snetworkplumbingwg#182

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* build: generate ip pool clientSet/informers/listers

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* vendor: update vendor stuff

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* build: vendor net-attach-def-client types

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* config: look for the whereabouts config file in multiple places

The reconciler controller will have access to the whereabouts
configuration via a mount point. As such, we need a way to specify its
path.

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* reconcile-loop: requires the IP ranges in normalized format

The IP reconcile loop also requires the IP ranges in a normalized
format; as such, we export it into a function, which will be used in a
follow-up commit.

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* config: allow IPAM config parsing from a NetConfList

Currently whereabouts is only able to parse network configurations in
the strict [0] format - i.e. **do not accept** a plugin list - [1].

The `ip-control-loop` must recover the full plugin configuration, which
may be in the network configuration format.

This commit allows whereabouts to now understand both formats.

Furthermore, the current CNI release - v1.0.Z - removed the support for
[0], meaning that only the configuration list format is now supported
[2].

[0] - https://github.com/containernetworking/cni/blob/v0.8.1/SPEC.md#network-configuration
[1] - https://github.com/containernetworking/cni/blob/v0.8.1/SPEC.md#network-configuration-lists
[2] - https://github.com/containernetworking/cni/blob/master/SPEC.md#released-versions

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* reconcile-loop: add a controller

Listen to pod deletion, and for every deleted pod, assure their IPs
are gone.

The rough algorithm goes like this:
  - for every network-status in the pod's annotations:
    - read associated net-attach-def from the k8s API
    - extract the range from the net-attach-def
    - find the corresponding IP pool
    - look for allocations belonging to the deleted pod
    - delete them using `IPManagement(..., types.Deallocate, ...)`

All the API reads go through the informer cache, which is kept updated
whenever the objects are updated on the API.

The dockerfiles are also updated, to ship this new binary.

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* e2e tests: remove manual cluster reconciliation

This would leave the `ip-control-loop` as the reconciliation tool.

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* unit tests: assure stale IPAllocation cleanup

This commit adds a unit where it is checked that the pod deletion leads
to the cleanup of a stale IP address.

This commit features the automatic provisioning of the controller informer cache
with the data present on the fake clientset tracker (the "fake" datastore).

This way, users can just create the client with provisioned data, and
that'll trickle down to the informer cache of the pod controller.

Because the `network-attachment-definitions` resources feature dashes,
the heuristic function that guesses - yes, guesses. very deterministic
... - the name of the resource can't be used - [0]. As such, it was
needed to create an alternate `newFakeNetAttachDefClient` where it is
possible to specify the correct resource name.

[0] - https://github.com/k8snetworkplumbingwg/network-attachment-definition-client/blob/2fd7267afcc4d48dfe6a8cd756b5a08bd04c2c97/vendor/k8s.io/client-go/testing/fixture.go#L331

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* unit tests: move helper funcs to other files

The helper files are tagged with the `test` build tag, to prevent them
from being shipped on the production code binary.

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* control loop, queueing: use a rate-limiting queue

Using a queue allows us to re-queue errors.

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* control loop: add IPAllocation cleanup related events

Adds two new events related to garbage collection of the whereabouts IP
addresses:
  - when an IP address is garbage collected
  - when a cleanup operation fails and is not re-queued

The former event looks like:
```
116s        Normal    IPAddressGarbageCollected   pod/macvlan1-worker1 \
            successful cleanup of IP address [192.168.2.1] from network \
            whereabouts-conf
```

The latter event looks like:
```
10s         Warning    IPAddressGarbageCollectionFailed    failed to garbage \
            collect addresses for pod default/macvlan1-worker1
```

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* e2e tests: check out statefulset scenarios

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* e2e tests: test different scale up/down order and instance deltas

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* ci: test e2e bash scripts last

These ugly tests do not cleanup after themselves; this way, the golang
based tests (which **do** cleanup after themselves) will not be impacted by
these left-overs.

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* ip control loop, unit tests: test negative scenarios

Check the event thrown when a request is dropped from the queue, and
assure reconciling an allocation is impossible without having access to
the attachment configuration data.

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* e2e tests: test fix for issue #182

Issue [0] reports an error when a pod associated to a `StatefulSet`
whose IPPool is already full is deleted. According to it, the new pod -
scheduled by the `StatefulSet` - cannot run because the IPPool is
already full, and the old pod's IP cannot be garbage collected because
we match by pod reference - and the "new" pod is stuck in `creating`
phase.

[0] - #182

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* ip-control-loop: strip pod before queueing it

The ip reconcile loop only requires the pod metadata and its network
status annotatations to garbage collect the stale IP addresses.

As such, we remove the status and spec parameters from the pod before
queueing it.

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* reconcile-loop: focus on networks w/ whereabouts IPAM type

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* build: generate ip pool clientSet/informers/listers

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* vendor: update vendor stuff

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* build: vendor net-attach-def-client types

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* config: look for the whereabouts config file in multiple places

The reconciler controller will have access to the whereabouts
configuration via a mount point. As such, we need a way to specify its
path.

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* reconcile-loop: requires the IP ranges in normalized format

The IP reconcile loop also requires the IP ranges in a normalized
format; as such, we export it into a function, which will be used in a
follow-up commit.

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* config: allow IPAM config parsing from a NetConfList

Currently whereabouts is only able to parse network configurations in
the strict [0] format - i.e. **do not accept** a plugin list - [1].

The `ip-control-loop` must recover the full plugin configuration, which
may be in the network configuration format.

This commit allows whereabouts to now understand both formats.

Furthermore, the current CNI release - v1.0.Z - removed the support for
[0], meaning that only the configuration list format is now supported
[2].

[0] - https://github.com/containernetworking/cni/blob/v0.8.1/SPEC.md#network-configuration
[1] - https://github.com/containernetworking/cni/blob/v0.8.1/SPEC.md#network-configuration-lists
[2] - https://github.com/containernetworking/cni/blob/master/SPEC.md#released-versions

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* reconcile-loop: add a controller

Listen to pod deletion, and for every deleted pod, assure their IPs
are gone.

The rough algorithm goes like this:
  - for every network-status in the pod's annotations:
    - read associated net-attach-def from the k8s API
    - extract the range from the net-attach-def
    - find the corresponding IP pool
    - look for allocations belonging to the deleted pod
    - delete them using `IPManagement(..., types.Deallocate, ...)`

All the API reads go through the informer cache, which is kept updated
whenever the objects are updated on the API.

The dockerfiles are also updated, to ship this new binary.

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* e2e tests: remove manual cluster reconciliation

This would leave the `ip-control-loop` as the reconciliation tool.

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* unit tests: assure stale IPAllocation cleanup

This commit adds a unit where it is checked that the pod deletion leads
to the cleanup of a stale IP address.

This commit features the automatic provisioning of the controller informer cache
with the data present on the fake clientset tracker (the "fake" datastore).

This way, users can just create the client with provisioned data, and
that'll trickle down to the informer cache of the pod controller.

Because the `network-attachment-definitions` resources feature dashes,
the heuristic function that guesses - yes, guesses. very deterministic
... - the name of the resource can't be used - [0]. As such, it was
needed to create an alternate `newFakeNetAttachDefClient` where it is
possible to specify the correct resource name.

[0] - https://github.com/k8snetworkplumbingwg/network-attachment-definition-client/blob/2fd7267afcc4d48dfe6a8cd756b5a08bd04c2c97/vendor/k8s.io/client-go/testing/fixture.go#L331

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* unit tests: move helper funcs to other files

The helper files are tagged with the `test` build tag, to prevent them
from being shipped on the production code binary.

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* control loop, queueing: use a rate-limiting queue

Using a queue allows us to re-queue errors.

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* control loop: add IPAllocation cleanup related events

Adds two new events related to garbage collection of the whereabouts IP
addresses:
  - when an IP address is garbage collected
  - when a cleanup operation fails and is not re-queued

The former event looks like:
```
116s        Normal    IPAddressGarbageCollected   pod/macvlan1-worker1 \
            successful cleanup of IP address [192.168.2.1] from network \
            whereabouts-conf
```

The latter event looks like:
```
10s         Warning    IPAddressGarbageCollectionFailed    failed to garbage \
            collect addresses for pod default/macvlan1-worker1
```

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* e2e tests: check out statefulset scenarios

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* e2e tests: test different scale up/down order and instance deltas

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* ci: test e2e bash scripts last

These ugly tests do not cleanup after themselves; this way, the golang
based tests (which **do** cleanup after themselves) will not be impacted by
these left-overs.

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* ip control loop, unit tests: test negative scenarios

Check the event thrown when a request is dropped from the queue, and
assure reconciling an allocation is impossible without having access to
the attachment configuration data.

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* e2e tests: test fix for issue k8snetworkplumbingwg#182

Issue [0] reports an error when a pod associated to a `StatefulSet`
whose IPPool is already full is deleted. According to it, the new pod -
scheduled by the `StatefulSet` - cannot run because the IPPool is
already full, and the old pod's IP cannot be garbage collected because
we match by pod reference - and the "new" pod is stuck in `creating`
phase.

[0] - k8snetworkplumbingwg#182

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* ip-control-loop: strip pod before queueing it

The ip reconcile loop only requires the pod metadata and its network
status annotatations to garbage collect the stale IP addresses.

As such, we remove the status and spec parameters from the pod before
queueing it.

Signed-off-by: Miguel Duarte Barroso <[email protected]>

* reconcile-loop: focus on networks w/ whereabouts IPAM type

Signed-off-by: Miguel Duarte Barroso <[email protected]>

Replaced bash e2e test with Golang e2e test (k8snetworkplumbingwg#181)

Fixed code errors causing e2e tests to not compile

Signed-off-by: nicklesimba <[email protected]>

e2e tests: remove manual ip pool reconciliation

Signed-off-by: Miguel Duarte Barroso <[email protected]>

e2e tests: use the default namespace

Signed-off-by: Miguel Duarte Barroso <[email protected]>

e2e tests: read the IPAllocations from the correct namespace

Furthermore, harden the `isIPPoolAllocationsEmpty` function - currently, if the
IPPool does not exist, it will be created without allocations. When that
happens, the pool is indeed empty.

Signed-off-by: Miguel Duarte Barroso <[email protected]>

Changed variable name for readability (envVars *envVars changed to
testConfig *envVars)

Signed-off-by: nicklesimba <[email protected]>