container

Documentation

Overview

Package container contains code related to dealing with docker containers

Index

• func ContainsWatchtowerLabel(labels map[string]string) bool
• func GetRunningContainerID() (cid types.ContainerID, err error)
• type Client
  • func NewClient(opts ClientOptions) Client
• type ClientOptions
• type Container
  • func NewContainer(containerInfo *types.ContainerJSON, imageInfo *types.ImageInspect) *Container
  • func (c Container) ContainerInfo() *types.ContainerJSON
  • func (c Container) Enabled() (bool, bool)
  • func (c Container) GetCreateConfig() *dockercontainer.Config
  • func (c Container) GetCreateHostConfig() *dockercontainer.HostConfig
  • func (c Container) GetLifecyclePostCheckCommand() string
  • func (c Container) GetLifecyclePostUpdateCommand() string
  • func (c Container) GetLifecyclePreCheckCommand() string
  • func (c Container) GetLifecyclePreUpdateCommand() string
  • func (c Container) HasImageInfo() bool
  • func (c Container) ID() wt.ContainerID
  • func (c Container) ImageID() wt.ImageID
  • func (c Container) ImageInfo() *types.ImageInspect
  • func (c Container) ImageName() string
  • func (c *Container) IsLinkedToRestarting() bool
  • func (c Container) IsMonitorOnly(params wt.UpdateParams) bool
  • func (c Container) IsNoPull(params wt.UpdateParams) bool
  • func (c Container) IsRestarting() bool
  • func (c Container) IsRunning() bool
  • func (c *Container) IsStale() bool
  • func (c Container) IsWatchtower() bool
  • func (c Container) Links() []string
  • func (c Container) Name() string
  • func (c Container) PostUpdateTimeout() int
  • func (c Container) PreUpdateTimeout() int
  • func (c Container) SafeImageID() wt.ImageID
  • func (c Container) Scope() (string, bool)
  • func (c *Container) SetLinkedToRestarting(value bool)
  • func (c *Container) SetStale(value bool)
  • func (c Container) StopSignal() string
  • func (c Container) ToRestart() bool
  • func (c Container) VerifyConfiguration() error
• type WarningStrategy

Functions

func ContainsWatchtowerLabel

func ContainsWatchtowerLabel(labels map[string]string) bool

ContainsWatchtowerLabel takes a map of labels and values and tells the consumer whether it contains a valid watchtower instance label

func GetRunningContainerID

func GetRunningContainerID() (cid types.ContainerID, err error)

GetRunningContainerID tries to resolve the current container ID from the current process cgroup information

Types

type Client

type Client interface {
	ListContainers(t.Filter) ([]t.Container, error)
	GetContainer(containerID t.ContainerID) (t.Container, error)
	StopContainer(t.Container, time.Duration) error
	StartContainer(t.Container) (t.ContainerID, error)
	RenameContainer(t.Container, string) error
	IsContainerStale(t.Container, t.UpdateParams) (stale bool, latestImage t.ImageID, err error)
	ExecuteCommand(containerID t.ContainerID, command string, timeout int) (SkipUpdate bool, err error)
	RemoveImageByID(t.ImageID) error
	WarnOnHeadPullFailed(container t.Container) bool
}

A Client is the interface through which watchtower interacts with the Docker API.

func NewClient

func NewClient(opts ClientOptions) Client

NewClient returns a new Client instance which can be used to interact with the Docker API. The client reads its configuration from the following environment variables:

• DOCKER_HOST the docker-engine host to send api requests to
• DOCKER_TLS_VERIFY whether to verify tls certificates
• DOCKER_API_VERSION the minimum docker api version to work with

type ClientOptions

type ClientOptions struct {
	RemoveVolumes     bool
	IncludeStopped    bool
	ReviveStopped     bool
	IncludeRestarting bool
	WarnOnHeadFailed  WarningStrategy
}

ClientOptions contains the options for how the docker client wrapper should behave

type Container

type Container struct {
	LinkedToRestarting bool
	Stale              bool
	// contains filtered or unexported fields
}

Container represents a running Docker container.

func NewContainer

func NewContainer(containerInfo *types.ContainerJSON, imageInfo *types.ImageInspect) *Container

NewContainer returns a new Container instance instantiated with the specified ContainerInfo and ImageInfo structs.

func (Container) ContainerInfo

func (c Container) ContainerInfo() *types.ContainerJSON

ContainerInfo fetches JSON info for the container

func (Container) Enabled

func (c Container) Enabled() (bool, bool)

Enabled returns the value of the container enabled label and if the label was set.

func (Container) GetCreateConfig

func (c Container) GetCreateConfig() *dockercontainer.Config

GetCreateConfig returns the container's current Config converted into a format that can be re-submitted to the Docker create API.

Ideally, we'd just be able to take the ContainerConfig from the old container and use it as the starting point for creating the new container; however, the ContainerConfig that comes back from the Inspect call merges the default configuration (the stuff specified in the metadata for the image itself) with the overridden configuration (the stuff that you might specify as part of the "docker run").

In order to avoid unintentionally overriding the defaults in the new image we need to separate the override options from the default options. To do this we have to compare the ContainerConfig for the running container with the ContainerConfig from the image that container was started from. This function returns a ContainerConfig which contains just the options overridden at runtime.

func (Container) GetCreateHostConfig

func (c Container) GetCreateHostConfig() *dockercontainer.HostConfig

GetCreateHostConfig returns the container's current HostConfig with any links re-written so that they can be re-submitted to the Docker create API.

func (Container) GetLifecyclePostCheckCommand

func (c Container) GetLifecyclePostCheckCommand() string

GetLifecyclePostCheckCommand returns the post-check command set in the container metadata or an empty string

func (Container) GetLifecyclePostUpdateCommand

func (c Container) GetLifecyclePostUpdateCommand() string

GetLifecyclePostUpdateCommand returns the post-update command set in the container metadata or an empty string

func (Container) GetLifecyclePreCheckCommand

func (c Container) GetLifecyclePreCheckCommand() string

GetLifecyclePreCheckCommand returns the pre-check command set in the container metadata or an empty string

func (Container) GetLifecyclePreUpdateCommand

func (c Container) GetLifecyclePreUpdateCommand() string

GetLifecyclePreUpdateCommand returns the pre-update command set in the container metadata or an empty string

func (Container) HasImageInfo

func (c Container) HasImageInfo() bool

HasImageInfo returns whether image information could be retrieved for the container

func (Container) ID

func (c Container) ID() wt.ContainerID

ID returns the Docker container ID.

func (Container) ImageID

func (c Container) ImageID() wt.ImageID

ImageID returns the ID of the Docker image that was used to start the container. May cause nil dereference if imageInfo is not set!

func (Container) ImageInfo

func (c Container) ImageInfo() *types.ImageInspect

ImageInfo fetches the ImageInspect data of the current container

func (Container) ImageName

func (c Container) ImageName() string

ImageName returns the name of the Docker image that was used to start the container. If the original image was specified without a particular tag, the "latest" tag is assumed.

func (*Container) IsLinkedToRestarting

func (c *Container) IsLinkedToRestarting() bool

IsLinkedToRestarting returns the current value of the LinkedToRestarting field for the container

func (Container) IsMonitorOnly

func (c Container) IsMonitorOnly(params wt.UpdateParams) bool

IsMonitorOnly returns whether the container should only be monitored based on values of the monitor-only label, the monitor-only argument and the label-take-precedence argument.

func (Container) IsNoPull

func (c Container) IsNoPull(params wt.UpdateParams) bool

IsNoPull returns whether the image should be pulled based on values of the no-pull label, the no-pull argument and the label-take-precedence argument.

func (Container) IsRestarting

func (c Container) IsRestarting() bool

IsRestarting returns a boolean flag indicating whether or not the current container is restarting. The status is determined by the value of the container's "State.Restarting" property.

func (Container) IsRunning

func (c Container) IsRunning() bool

IsRunning returns a boolean flag indicating whether or not the current container is running. The status is determined by the value of the container's "State.Running" property.

func (*Container) IsStale

func (c *Container) IsStale() bool

IsStale returns the current value of the Stale field for the container

func (Container) IsWatchtower

func (c Container) IsWatchtower() bool

IsWatchtower returns a boolean flag indicating whether or not the current container is the watchtower container itself. The watchtower container is identified by the presence of the "com.centurylinklabs.watchtower" label in the container metadata.

func (Container) Links

func (c Container) Links() []string

Links returns a list containing the names of all the containers to which this container is linked.

func (Container) Name

func (c Container) Name() string

Name returns the Docker container name.

func (Container) PostUpdateTimeout

func (c Container) PostUpdateTimeout() int

PostUpdateTimeout checks whether a container has a specific timeout set for how long the post-update command is allowed to run. This value is expressed either as an integer, in minutes, or as 0 which will allow the command/script to run indefinitely. Users should be cautious with the 0 option, as that could result in watchtower waiting forever.

func (Container) PreUpdateTimeout

func (c Container) PreUpdateTimeout() int

PreUpdateTimeout checks whether a container has a specific timeout set for how long the pre-update command is allowed to run. This value is expressed either as an integer, in minutes, or as 0 which will allow the command/script to run indefinitely. Users should be cautious with the 0 option, as that could result in watchtower waiting forever.

func (Container) SafeImageID

func (c Container) SafeImageID() wt.ImageID

SafeImageID returns the ID of the Docker image that was used to start the container if available, otherwise returns an empty string

func (Container) Scope

func (c Container) Scope() (string, bool)

Scope returns the value of the scope UID label and if the label was set.

func (*Container) SetLinkedToRestarting

func (c *Container) SetLinkedToRestarting(value bool)

SetLinkedToRestarting sets the LinkedToRestarting field for the container

func (*Container) SetStale

func (c *Container) SetStale(value bool)

SetStale implements sets the Stale field for the container

func (Container) StopSignal

func (c Container) StopSignal() string

StopSignal returns the custom stop signal (if any) that is encoded in the container's metadata. If the container has not specified a custom stop signal, the empty string "" is returned.

func (Container) ToRestart

func (c Container) ToRestart() bool

ToRestart return whether the container should be restarted, either because is stale or linked to another stale container.

func (Container) VerifyConfiguration

func (c Container) VerifyConfiguration() error

VerifyConfiguration checks the container and image configurations for nil references to make sure that the container can be recreated once deleted

type WarningStrategy

type WarningStrategy string

WarningStrategy is a value determining when to show warnings

const (
	// WarnAlways warns whenever the problem occurs
	WarnAlways WarningStrategy = "always"
	// WarnNever never warns when the problem occurs
	WarnNever WarningStrategy = "never"
	// WarnAuto skips warning when the problem was expected
	WarnAuto WarningStrategy = "auto"
)