Add basic skeletons of state handling, containers and pods

Signed-off-by: Matthew Heon <mheon@redhat.com>
This commit is contained in:
Matthew Heon 2017-09-06 11:15:11 -04:00
parent 2850fb60a5
commit 35e951fc8c
5 changed files with 376 additions and 27 deletions

View file

@ -2,8 +2,12 @@ package libpod
import (
"fmt"
"sync"
"github.com/containers/storage"
"github.com/docker/docker/pkg/stringid"
spec "github.com/opencontainers/runtime-spec/specs-go"
"github.com/ulule/deepcopier"
)
var (
@ -13,7 +17,60 @@ var (
// Container is a single OCI container
type Container struct {
// TODO populate
id string
name string
spec *spec.Spec
pod *Pod
valid bool
lock sync.RWMutex
}
// ID returns the container's ID
func (c *Container) ID() string {
// No locking needed, ID will never mutate after a container is created
return c.id
}
// Name returns the container's name
func (c *Container) Name() string {
// Name can potentially be changed while a container is running
// So lock access to it
c.lock.RLock()
defer c.lock.RUnlock()
return c.name
}
// Spec returns the container's OCI runtime spec
func (c *Container) Spec() *spec.Spec {
// The spec can potentially be altered when storage is configured and to
// add annotations at container create time
// As such, access to it is locked
c.lock.RLock()
defer c.lock.RUnlock()
spec := new(spec.Spec)
deepcopier.Copy(c.spec).To(spec)
return spec
}
// Make a new container
func newContainer(rspec *spec.Spec) (*Container, error) {
if rspec == nil {
return nil, fmt.Errorf("must provide a valid spec to construct container")
}
ctr := new(Container)
ctr.id = stringid.GenerateNonCryptoID()
ctr.name = ctr.id // TODO generate unique human-readable names
ctr.spec = new(spec.Spec)
deepcopier.Copy(rspec).To(ctr.spec)
return ctr, nil
}
// Create creates a container in the OCI runtime

View file

@ -18,7 +18,6 @@ import (
"github.com/containers/storage"
"github.com/containers/storage/pkg/archive"
"github.com/kubernetes-incubator/cri-o/libpod/common"
"github.com/kubernetes-incubator/cri-o/libpod/ctr"
"github.com/kubernetes-incubator/cri-o/libpod/images"
"github.com/pkg/errors"
)
@ -354,10 +353,10 @@ func (r *Runtime) GetImageRef(image string) (types.Image, error) {
// output. Multiple filters are handled by ANDing their output, so only images
// matching all filters are included
func (r *Runtime) GetImages(filter ...ImageFilter) ([]*storage.Image, error) {
return nil, ctr.ErrNotImplemented
return nil, errNotImplemented
}
// ImportImage imports an OCI format image archive into storage as an image
func (r *Runtime) ImportImage(path string) (*storage.Image, error) {
return nil, ctr.ErrNotImplemented
return nil, errNotImplemented
}

View file

@ -5,10 +5,12 @@ import (
"github.com/containers/storage"
"github.com/containers/storage/pkg/idtools"
"github.com/pkg/errors"
)
var (
errRuntimeFinalized = fmt.Errorf("runtime has already been finalized")
errCtrFinalized = fmt.Errorf("container has already been finalized")
ctrNotImplemented = func(c *Container) error {
return fmt.Errorf("NOT IMPLEMENTED")
}
@ -201,8 +203,31 @@ func WithSharedNamespaces(from *Container, namespaces map[string]string) CtrCrea
}
// WithPod adds the container to a pod
func WithPod(pod *Pod) CtrCreateOption {
return ctrNotImplemented
func (r *Runtime) WithPod(pod *Pod) CtrCreateOption {
return func(ctr *Container) error {
if !ctr.valid {
return errCtrFinalized
}
if ctr.pod != nil {
return fmt.Errorf("container has already been added to a pod")
}
exists, err := r.state.HasPod(pod.ID())
if err != nil {
return errors.Wrapf(err, "error searching state for pod %s", pod.ID())
} else if !exists {
return fmt.Errorf("pod with id %s not found in state")
}
if err := pod.addContainer(ctr); err != nil {
return errors.Wrapf(err, "error adding container to pod")
}
ctr.pod = pod
return nil
}
}
// WithLabels adds labels to the pod
@ -217,10 +242,33 @@ func WithAnnotations(annotations map[string]string) CtrCreateOption {
// WithName sets the container's name
func WithName(name string) CtrCreateOption {
return ctrNotImplemented
return func(ctr *Container) error {
if !ctr.valid {
return errCtrFinalized
}
ctr.name = name
return nil
}
}
// WithStopSignal sets the signal that will be sent to stop the container
func WithStopSignal(signal uint) CtrCreateOption {
return ctrNotImplemented
}
// Pod Creation Options
// WithPodName sets the name of the pod
func WithPodName(name string) PodCreateOption {
return func(pod *Pod) error {
if pod.valid {
return fmt.Errorf("pod already finalized")
}
pod.name = name
return nil
}
}

View file

@ -1,12 +1,81 @@
package libpod
import (
"github.com/kubernetes-incubator/cri-o/libpod/ctr"
"fmt"
"sync"
"github.com/docker/docker/pkg/stringid"
)
// Pod represents a group of containers that may share namespaces
type Pod struct {
// TODO populate
id string
name string
containers map[string]*Container
valid bool
lock sync.RWMutex
}
// ID retrieves the pod's ID
func (p *Pod) ID() string {
return p.id
}
// Name retrieves the pod's name
func (p *Pod) Name() string {
return p.name
}
// Creates a new pod
func newPod() (*Pod, error) {
pod := new(Pod)
pod.id = stringid.GenerateNonCryptoID()
pod.name = pod.id // TODO generate human-readable name here
pod.containers = make(map[string]*Container)
return pod, nil
}
// Adds a container to the pod
// Does not check that container's pod ID is set correctly, or attempt to set
// pod ID after adding
func (p *Pod) addContainer(ctr *Container) error {
p.lock.Lock()
defer p.lock.Unlock()
if !p.valid {
return fmt.Errorf("pod has already been removed")
}
if _, ok := p.containers[ctr.id]; ok {
return fmt.Errorf("container with id %s already exists in pod %s", ctr.id, p.id)
}
p.containers[ctr.id] = ctr
return nil
}
// Removes a container from the pod
// Does not perform any checks on the container
func (p *Pod) removeContainer(ctr *Container) error {
p.lock.Lock()
defer p.lock.Unlock()
if !p.valid {
return fmt.Errorf("pod has already been removed")
}
if _, ok := p.containers[ctr.id]; !ok {
return fmt.Errorf("container with id %s does not exist in pod %s", ctr.id, p.id)
}
delete(p.containers, ctr.id)
return nil
}
// Start starts all containers within a pod that are not already running
@ -26,7 +95,19 @@ func (p *Pod) Kill(signal uint) error {
// GetContainers retrieves the containers in the pod
func (p *Pod) GetContainers() ([]*Container, error) {
return nil, errNotImplemented
p.lock.RLock()
defer p.lock.RUnlock()
if !p.valid {
return nil, fmt.Errorf("pod has already been removed")
}
ctrs := make([]*Container, 0, len(p.containers))
for _, ctr := range p.containers {
ctrs = append(ctrs, ctr)
}
return ctrs, nil
}
// Status gets the status of all containers in the pod

View file

@ -20,6 +20,7 @@ type RuntimeOption func(*Runtime) error
// Runtime is the core libpod runtime
type Runtime struct {
config *RuntimeConfig
state State
store storage.Store
imageContext *types.SystemContext
apparmorEnabled bool
@ -145,45 +146,158 @@ type ContainerFilter func(*Container) bool
// NewContainer creates a new container from a given OCI config
func (r *Runtime) NewContainer(spec *spec.Spec, options ...CtrCreateOption) (*Container, error) {
return nil, ctr.ErrNotImplemented
r.lock.Lock()
defer r.lock.Unlock()
if !r.valid {
return nil, fmt.Errorf("runtime has already been shut down")
}
ctr, err := newContainer(spec)
if err != nil {
return nil, err
}
for _, option := range options {
if err := option(ctr); err != nil {
return nil, errors.Wrapf(err, "error running container create option")
}
}
ctr.valid = true
if err := r.state.AddContainer(ctr); err != nil {
// If we joined a pod, remove ourself from it
if ctr.pod != nil {
if err2 := ctr.pod.removeContainer(ctr); err2 != nil {
return nil, errors.Wrapf(err, "error adding new container to state, container could not be removed from pod %s", ctr.pod.ID())
}
}
// TODO: Might be worth making an effort to detect duplicate IDs
// We can recover from that by generating a new ID for the
// container
return nil, errors.Wrapf(err, "error adding new container to state")
}
return ctr, nil
}
// RemoveContainer removes the given container
// If force is specified, the container will be stopped first
// Otherwise, RemoveContainer will return an error if the container is running
func (r *Runtime) RemoveContainer(c *Container, force bool) error {
return ctr.ErrNotImplemented
return errNotImplemented
}
// GetContainer retrieves a container by its ID
func (r *Runtime) GetContainer(id string) (*ctr.Container, error) {
return nil, ctr.ErrNotImplemented
func (r *Runtime) GetContainer(id string) (*Container, error) {
r.lock.RLock()
defer r.lock.RUnlock()
if !r.valid {
return nil, fmt.Errorf("runtime has already been shut down")
}
return r.state.GetContainer(id)
}
// HasContainer checks if a container with the given ID is present
func (r *Runtime) HasContainer(id string) (bool, error) {
r.lock.RLock()
defer r.lock.RUnlock()
if !r.valid {
return false, fmt.Errorf("runtime has already been shut down")
}
return r.state.HasContainer(id)
}
// LookupContainer looks up a container by its name or a partial ID
// If a partial ID is not unique, an error will be returned
func (r *Runtime) LookupContainer(idOrName string) (*ctr.Container, error) {
return nil, ctr.ErrNotImplemented
func (r *Runtime) LookupContainer(idOrName string) (*Container, error) {
r.lock.RLock()
defer r.lock.RUnlock()
if !r.valid {
return nil, fmt.Errorf("runtime has already been shut down")
}
return r.state.LookupContainer(idOrName)
}
// GetContainers retrieves all containers from the state
// Filters can be provided which will determine what containers are included in
// the output. Multiple filters are handled by ANDing their output, so only
// containers matching all filters are returned
func (r *Runtime) GetContainers(filters ...ContainerFilter) ([]*ctr.Container, error) {
return nil, ctr.ErrNotImplemented
func (r *Runtime) GetContainers(filters ...ContainerFilter) ([]*Container, error) {
r.lock.RLock()
defer r.lock.RUnlock()
if !r.valid {
return nil, fmt.Errorf("runtime has already been shut down")
}
ctrs, err := r.state.GetAllContainers()
if err != nil {
return nil, err
}
ctrsFiltered := make([]*Container, 0, len(ctrs))
for _, ctr := range ctrs {
include := true
for _, filter := range filters {
include = include && filter(ctr)
}
if include {
ctrsFiltered = append(ctrsFiltered, ctr)
}
}
return ctrsFiltered, nil
}
// Pod API
// A PodCreateOption is a functional option which alters the Pod created by
// NewPod
type PodCreateOption func(*Pod) error
// PodFilter is a function to determine whether a pod is included in command
// output. Pods to be outputted are tested using the function. A true return
// will include the pod, a false return will exclude it.
type PodFilter func(*Pod) bool
// NewPod makes a new, empty pod
func (r *Runtime) NewPod() (*pod.Pod, error) {
return nil, ctr.ErrNotImplemented
func (r *Runtime) NewPod(options ...PodCreateOption) (*Pod, error) {
r.lock.Lock()
defer r.lock.Unlock()
if !r.valid {
return nil, fmt.Errorf("runtime has already been shut down")
}
pod, err := newPod()
if err != nil {
return nil, errors.Wrapf(err, "error creating pod")
}
for _, option := range options {
if err := option(pod); err != nil {
return nil, errors.Wrapf(err, "error running pod create option")
}
}
pod.valid = true
if err := r.state.AddPod(pod); err != nil {
return nil, errors.Wrapf(err, "error adding pod to state")
}
return nil, errNotImplemented
}
// RemovePod removes a pod and all containers in it
@ -191,24 +305,74 @@ func (r *Runtime) NewPod() (*pod.Pod, error) {
// Otherwise, RemovePod will return an error if any container in the pod is running
// Remove acts atomically, removing all containers or no containers
func (r *Runtime) RemovePod(p *Pod, force bool) error {
return ctr.ErrNotImplemented
return errNotImplemented
}
// GetPod retrieves a pod by its ID
func (r *Runtime) GetPod(id string) (*pod.Pod, error) {
return nil, ctr.ErrNotImplemented
func (r *Runtime) GetPod(id string) (*Pod, error) {
r.lock.RLock()
defer r.lock.RUnlock()
if !r.valid {
return nil, fmt.Errorf("runtime has already been shut down")
}
return r.state.GetPod(id)
}
// HasPod checks to see if a pod with the given ID exists
func (r *Runtime) HasPod(id string) (bool, error) {
r.lock.RLock()
defer r.lock.RUnlock()
if !r.valid {
return false, fmt.Errorf("runtime has already been shut down")
}
return r.state.HasPod(id)
}
// LookupPod retrieves a pod by its name or a partial ID
// If a partial ID is not unique, an error will be returned
func (r *Runtime) LookupPod(idOrName string) (*pod.Pod, error) {
return nil, ctr.ErrNotImplemented
func (r *Runtime) LookupPod(idOrName string) (*Pod, error) {
r.lock.RLock()
defer r.lock.RUnlock()
if !r.valid {
return nil, fmt.Errorf("runtime has already been shut down")
}
return r.state.LookupPod(idOrName)
}
// GetPods retrieves all pods
// Filters can be provided which will determine which pods are included in the
// output. Multiple filters are handled by ANDing their output, so only pods
// matching all filters are returned
func (r *Runtime) GetPods(filters ...PodFilter) ([]*pod.Pod, error) {
return nil, ctr.ErrNotImplemented
func (r *Runtime) GetPods(filters ...PodFilter) ([]*Pod, error) {
r.lock.RLock()
defer r.lock.RUnlock()
if !r.valid {
return nil, fmt.Errorf("runtime has already been shut down")
}
pods, err := r.state.GetAllPods()
if err != nil {
return nil, err
}
podsFiltered := make([]*Pod, 0, len(pods))
for _, pod := range pods {
include := true
for _, filter := range filters {
include = include && filter(pod)
}
if include {
podsFiltered = append(podsFiltered, pod)
}
}
return podsFiltered, nil
}