diff options
| -rw-r--r-- | libpod/container_api.go | 69 | ||||
| -rw-r--r-- | libpod/container_internal.go | 107 | ||||
| -rw-r--r-- | libpod/pod.go | 115 |
3 files changed, 234 insertions, 57 deletions
diff --git a/libpod/container_api.go b/libpod/container_api.go index 0a27da7c9..7e2197614 100644 --- a/libpod/container_api.go +++ b/libpod/container_api.go @@ -59,35 +59,11 @@ func (c *Container) Init() (err error) { } }() - if err := c.makeBindMounts(); err != nil { - return err - } - - // Generate the OCI spec - spec, err := c.generateSpec() - if err != nil { - return err - } - - // Save the OCI spec to disk - if err := c.saveSpec(spec); err != nil { - return err - } - - // With the spec complete, do an OCI create - if err := c.runtime.ociRuntime.createContainer(c, c.config.CgroupParent); err != nil { - return err - } - - logrus.Debugf("Created container %s in OCI runtime", c.ID()) - - c.state.State = ContainerStateCreated - - return c.save() + return c.init() } // Start starts a container -func (c *Container) Start() error { +func (c *Container) Start() (err error) { if !c.locked { c.lock.Lock() defer c.lock.Unlock() @@ -107,20 +83,33 @@ func (c *Container) Start() error { return errors.Wrapf(ErrNotImplemented, "restarting a stopped container is not yet supported") } - // Mount storage for the container + // Mount storage for the container if necessary if err := c.mountStorage(); err != nil { return err } + defer func() { + if err != nil { + if err2 := c.cleanupStorage(); err2 != nil { + logrus.Errorf("Error cleaning up storage for container %s: %v", c.ID(), err2) + } + } + }() - if err := c.runtime.ociRuntime.startContainer(c); err != nil { - return err + // Create a network namespace if necessary + if c.config.CreateNetNS && c.state.NetNS == nil { + if err := c.runtime.createNetNS(c); err != nil { + return err + } } + defer func() { + if err != nil { + if err2 := c.runtime.teardownNetNS(c); err2 != nil { + logrus.Errorf("Error tearing down network namespace for container %s: %v", c.ID(), err2) + } + } + }() - logrus.Debugf("Started container %s", c.ID()) - - c.state.State = ContainerStateRunning - - return c.save() + return c.start() } // Stop uses the container's stop signal (or SIGTERM if no signal was specified) @@ -138,6 +127,12 @@ func (c *Container) Stop() error { } } + if c.state.State == ContainerStateConfigured || + c.state.State == ContainerStateUnknown || + c.state.State == ContainerStatePaused { + return errors.Wrapf(ErrCtrStateInvalid, "can only stop created, running, or stopped containers") + } + return c.stop(c.config.StopTimeout) } @@ -154,6 +149,12 @@ func (c *Container) StopWithTimeout(timeout uint) error { } } + if c.state.State == ContainerStateConfigured || + c.state.State == ContainerStateUnknown || + c.state.State == ContainerStatePaused { + return errors.Wrapf(ErrCtrStateInvalid, "can only stop created, running, or stopped containers") + } + return c.stop(timeout) } diff --git a/libpod/container_internal.go b/libpod/container_internal.go index 3c7637717..ba11dd2c6 100644 --- a/libpod/container_internal.go +++ b/libpod/container_internal.go @@ -313,16 +313,111 @@ func (c *Container) save() error { return nil } +// Initialize a container, creating it in the runtime +func (c *Container) init() error { + if err := c.makeBindMounts(); err != nil { + return err + } + + // Generate the OCI spec + spec, err := c.generateSpec() + if err != nil { + return err + } + + // Save the OCI spec to disk + if err := c.saveSpec(spec); err != nil { + return err + } + + // With the spec complete, do an OCI create + if err := c.runtime.ociRuntime.createContainer(c, c.config.CgroupParent); err != nil { + return err + } + + logrus.Debugf("Created container %s in OCI runtime", c.ID()) + + c.state.State = ContainerStateCreated + + return c.save() +} + +// Initialize (if necessary) and start a container +// Performs all necessary steps to start a container that is not running +// Does not lock or check validity +func (c *Container) initAndStart() (err error) { + // If we are ContainerStateUnknown, throw an error + if c.state.State == ContainerStateUnknown { + return errors.Wrapf(ErrCtrStateInvalid, "container %s is in an unknown state", c.ID()) + } + + // If we are running, do nothing + if c.state.State == ContainerStateRunning { + return nil + } + // If we are paused, throw an error + if c.state.State == ContainerStatePaused { + return errors.Wrapf(ErrCtrStateInvalid, "cannot start paused container %s", c.ID()) + } + // TODO remove this once we can restart containers + if c.state.State == ContainerStateStopped { + return errors.Wrapf(ErrNotImplemented, "restarting containers is not yet implemented") + } + + // Mount if necessary + if err := c.mountStorage(); err != nil { + return err + } + defer func() { + if err != nil { + if err2 := c.cleanupStorage(); err2 != nil { + logrus.Errorf("Error cleaning up storage for container %s: %v", c.ID(), err2) + } + } + }() + + // Create a network namespace if necessary + if c.config.CreateNetNS && c.state.NetNS == nil { + if err := c.runtime.createNetNS(c); err != nil { + return err + } + } + defer func() { + if err != nil { + if err2 := c.runtime.teardownNetNS(c); err2 != nil { + logrus.Errorf("Error tearing down network namespace for container %s: %v", c.ID(), err2) + } + } + }() + + // If we are ContainerStateConfigured we need to init() + if c.state.State == ContainerStateConfigured { + if err := c.init(); err != nil { + return err + } + } + + // Now start the container + return c.start() +} + +// Internal, non-locking function to start a container +func (c *Container) start() error { + if err := c.runtime.ociRuntime.startContainer(c); err != nil { + return err + } + + logrus.Debugf("Started container %s", c.ID()) + + c.state.State = ContainerStateRunning + + return c.save() +} + // Internal, non-locking function to stop container func (c *Container) stop(timeout uint) error { logrus.Debugf("Stopping ctr %s with timeout %d", c.ID(), timeout) - if c.state.State == ContainerStateConfigured || - c.state.State == ContainerStateUnknown || - c.state.State == ContainerStatePaused { - return errors.Wrapf(ErrCtrStateInvalid, "can only stop created, running, or stopped containers") - } - if err := c.runtime.ociRuntime.stopContainer(c, timeout); err != nil { return err } diff --git a/libpod/pod.go b/libpod/pod.go index a5b05d090..148093912 100644 --- a/libpod/pod.go +++ b/libpod/pod.go @@ -68,12 +68,13 @@ func newPod(lockDir string, runtime *Runtime) (*Pod, error) { return pod, nil } -// Init initializes all containers within a pod that have not been initialized -func (p *Pod) Init() error { - return ErrNotImplemented -} +// TODO: need function to produce a directed graph of containers +// This would allow us to properly determine stop/start order // Start starts all containers within a pod +// It combines the effects of Init() and Start() on a container +// If a container has already been initialized it will be started, +// otherwise it will be initialized then started. // Containers that are already running or have been paused are ignored // All containers are started independently, in order dictated by their // dependencies. @@ -97,6 +98,11 @@ func (p *Pod) Start() (map[string]error, error) { return nil, err } + // Maintain a map of containers still to start + ctrsToStart := make(map[string]*Container) + // Maintain a map of all containers so we can easily look up dependencies + allCtrsMap := make(map[string]*Container) + // We need to lock all the containers for _, ctr := range allCtrs { ctr.lock.Lock() @@ -105,10 +111,80 @@ func (p *Pod) Start() (map[string]error, error) { if err := ctr.syncContainer(); err != nil { return nil, err } + + if ctr.state.State == ContainerStateConfigured || + ctr.state.State == ContainerStateCreated || + ctr.state.State == ContainerStateStopped { + ctrsToStart[ctr.ID()] = ctr + } + allCtrsMap[ctr.ID()] = ctr } ctrErrors := make(map[string]error) + // Loop at most 10 times, to prevent potential infinite loops in + // dependencies + loopCounter := 10 + + // Loop while we still have containers to start + for len(ctrsToStart) > 0 { + // Loop through all containers, attempting to start them + for id, ctr := range ctrsToStart { + // TODO remove this when we support restarting containers + if ctr.state.State == ContainerStateStopped { + ctrErrors[id] = errors.Wrapf(ErrNotImplemented, "starting stopped containers is not yet supported") + + delete(ctrsToStart, id) + continue + } + + // TODO should we only do a dependencies check if we are not ContainerStateCreated? + depsOK := true + var depErr error + // Check container dependencies + for _, depID := range ctr.Dependencies() { + depCtr := allCtrsMap[depID] + if depCtr.state.State != ContainerStateRunning && + depCtr.state.State != ContainerStatePaused { + // We are definitely not OK to init, a dependency is not up + depsOK = false + // Check to see if the dependency errored + // If it did, error here too + if _, ok := ctrErrors[depID]; ok { + depErr = errors.Wrapf(ErrCtrStateInvalid, "dependency %s of container %s failed to start", depID, id) + } + + break + } + } + if !depsOK { + // Only if one of the containers dependencies failed should we stop trying + // Otherwise, assume it's just yet to start, retry starting this container later + if depErr != nil { + ctrErrors[id] = depErr + delete(ctrsToStart, id) + } + continue + } + + // Initialize and start the container + if err := ctr.initAndStart(); err != nil { + ctrErrors[id] = err + } + delete(ctrsToStart, id) + } + + loopCounter = loopCounter - 1 + if loopCounter == 0 { + // Loop through all remaining containers and add an error + for id := range ctrsToStart { + ctrErrors[id] = errors.Wrapf(ErrInternal, "exceeded maximum attempts trying to start container %s", id) + } + + break + } + } + // Start all containers for _, ctr := range allCtrs { // Ignore containers that are not created or stopped @@ -148,6 +224,8 @@ func (p *Pod) Start() (map[string]error, error) { // Each container will use its own stop timeout // Only running containers will be stopped. Paused, stopped, or created // containers will be ignored. +// If cleanup is true, mounts and network namespaces will be cleaned up after +// the container is stopped. // All containers are stopped independently. An error stopping one container // will not prevent other containers being stopped. // An error and a map[string]error are returned @@ -157,7 +235,7 @@ func (p *Pod) Start() (map[string]error, error) { // containers. The container ID is mapped to the error encountered. The error is // set to ErrCtrExists // If both error and the map are nil, all containers were stopped without error -func (p *Pod) Stop() (map[string]error, error) { +func (p *Pod) Stop(cleanup bool) (map[string]error, error) { p.lock.Lock() defer p.lock.Unlock() @@ -182,6 +260,9 @@ func (p *Pod) Stop() (map[string]error, error) { ctrErrors := make(map[string]error) + // TODO: There may be cases where it makes sense to order stops based on + // dependencies. Should we bother with this? + // Stop to all containers for _, ctr := range allCtrs { // Ignore containers that are not running @@ -189,22 +270,22 @@ func (p *Pod) Stop() (map[string]error, error) { continue } - if err := ctr.runtime.ociRuntime.stopContainer(ctr, ctr.config.StopTimeout); err != nil { - ctrErrors[ctr.ID()] = err - continue - } - - logrus.Debugf("Stopped container %s", ctr.ID()) - - // Sync container state to pick up return code - if err := ctr.runtime.ociRuntime.updateContainerStatus(ctr); err != nil { + if err := ctr.stop(ctr.config.StopTimeout); err != nil { ctrErrors[ctr.ID()] = err continue } - // Clean up storage to ensure we don't leave dangling mounts - if err := ctr.cleanupStorage(); err != nil { - ctrErrors[ctr.ID()] = err + if cleanup { + // Clean up storage to ensure we don't leave dangling mounts + if err := ctr.cleanupStorage(); err != nil { + ctrErrors[ctr.ID()] = err + continue + } + + // Clean up network namespace + if err := ctr.cleanupNetwork(); err != nil { + ctrErrors[ctr.ID()] = err + } } } |