Closes#606
This lets the unit tests be runnable on linux. The change:
- Adds a linux-test makefile target so we can run the unit tests locally
- Fixes up some test code to work on Linux (mostly ifdefs)
- Runs the unit tests in CI now
The network protocol and VMNetNetwork implementation currently are
housed on ContainerManager even though they are generally useful types
even outside of this easy to use helper type. This change moves them to
not be nested types anymore, as well as exposes a new param on
VMNetNetworks constructor so we can pass the type of network.
This PR adds a `networking: Bool = true` parameter to
`ContainerManager.create()` so callers can opt out of network interface
creation on a per-container basis.
## Motivation
Currently, `ContainerManager.create()` unconditionally allocates a vmnet
network interface for every container (when the manager has a network
configured). Some use cases don't need network access and benefit from
having it disabled to reduce attack surface.
There's no way to achieve this today without either:
- Initializing the `ContainerManager` without a network (which disables
networking for *all* containers)
- Clearing `config.interfaces` in the configuration closure (which
wastes an IP allocation from the vmnet pool since `network.create(id)`
has already been called)
## Changes
- Add `networking: Bool = true` to all three `create()` overloads on
`ContainerManager`
- When `false`, `self.network?.create(id)` is skipped entirely. No
interface is allocated, and no DNS is configured.
- `releaseNetwork`/`delete` remain safe to call regardless, since
`Allocator.release` silently ignores unknown IDs.
- Add unit test `testNetworkingFalseSkipsInterfaceCreation` using the
existing `NilGatewayNetwork` fixture
- Add integration tests `testNetworkingDisabled` and
`testNetworkingEnabled` that create containers through a network-enabled
`ContainerManager` and verify the presence/absence of `eth0` via
`/sys/class/net/`
- Guarded against ipv4Gateway if nil and throw
`ContainerizationError(.invalidState, ...)` instead of force unwraping
- Added a unit test
`ContainerManagerTests.testCreateThrowsWhenGatewayMissing`