systemd

Documentation

Index

• Constants
• func Available() error
• func EscapeUnitNamePath(in string) string
• func IsTimeout(err error) bool
• func MockJournalctl(f func(svcs []string, n int, follow bool) (io.ReadCloser, error)) func()
• func MockStopDelays(checkDelay, notifyDelay time.Duration) func()
• func MockSystemctl(f func(args ...string) ([]byte, error)) func()
• func MockSystemdSysctl(f func(args ...string) error) func()
• func MountUnitPath(baseDir string) string
• func NewJournalStreamFile(identifier string, priority syslog.Priority, levelPrefix bool) (*os.File, error)
• func SdNotify(notifyState string) error
• func Sysctl(prefixes []string) error
• func Version() (int, error)
• type Error
  • func (e *Error) Error() string
  • func (e *Error) ExitCode() int
  • func (e *Error) Msg() []byte
• type InstanceMode
• type Log
  • func (l Log) Message() string
  • func (l Log) PID() string
  • func (l Log) SID() string
  • func (l Log) Time() (time.Time, error)
• type Systemd
  • func New(mode InstanceMode, rep reporter) Systemd
  • func NewEmulationMode(rootDir string) Systemd
  • func NewUnderRoot(rootDir string, mode InstanceMode, rep reporter) Systemd
• type Timeout
  • func (e *Timeout) Error() string
• type UnitStatus

Constants

const (
	// the default target for systemd units that we generate
	ServicesTarget = "multi-user.target"

	// the target prerequisite for systemd units we generate
	PrerequisiteTarget = "network.target"

	// the default target for systemd socket units that we generate
	SocketsTarget = "sockets.target"

	// the default target for systemd timer units that we generate
	TimersTarget = "timers.target"

	// the target for systemd user session units that we generate
	UserServicesTarget = "default.target"
)

Functions

func Available

func Available() error

func EscapeUnitNamePath

func EscapeUnitNamePath(in string) string

EscapeUnitNamePath works like systemd-escape --path FIXME: we could use github.com/coreos/go-systemd/unit/escape.go

and EscapePath from it.

But thats not in the archive and it won't work with go1.3

func IsTimeout

func IsTimeout(err error) bool

IsTimeout checks whether the given error is a Timeout

func MockJournalctl

func MockJournalctl(f func(svcs []string, n int, follow bool) (io.ReadCloser, error)) func()

func MockStopDelays

func MockStopDelays(checkDelay, notifyDelay time.Duration) func()

MockStopDelays is used from tests so that Stop can be less forgiving there.

func MockSystemctl

func MockSystemctl(f func(args ...string) ([]byte, error)) func()

MockSystemctl is called from the commands to actually call out to systemctl. It's exported so it can be overridden by testing.

func MockSystemdSysctl

func MockSystemdSysctl(f func(args ...string) error) func()

MockSystemdSysctl lets mock and intercept calls to systemd-sysctl from the package.

func MountUnitPath

func MountUnitPath(baseDir string) string

MountUnitPath returns the path of a {,auto}mount unit

func NewJournalStreamFile

func NewJournalStreamFile(identifier string, priority syslog.Priority, levelPrefix bool) (*os.File, error)

NewJournalStreamFile creates log stream file descriptor to the journal. The semantics is identical to that of sd_journal_stream_fd(3) call.

func SdNotify

func SdNotify(notifyState string) error

SdNotify sends the given state string notification to systemd.

inspired by libsystemd/sd-daemon/sd-daemon.c from the systemd source

func Sysctl

func Sysctl(prefixes []string) error

Sysctl invokes systemd-sysctl to configure sysctl(8) kernel parameters from disk configuration. A set of prefixes can be passed to limit which settings are (re)configured.

func Version

func Version() (int, error)

Version returns systemd version.

Types

type Error

type Error struct {
	// contains filtered or unexported fields
}

Error is returned if the systemd action failed

func (*Error) Error

func (e *Error) Error() string

func (*Error) ExitCode

func (e *Error) ExitCode() int

func (*Error) Msg

func (e *Error) Msg() []byte

type InstanceMode

type InstanceMode int

InstanceMode determines which instance of systemd to control.

SystemMode refers to the system instance (i.e. pid 1). UserMode refers to the instance launched to manage the user's desktop session. GlobalUserMode controls configuration respected by all user instances on the system.

As GlobalUserMode does not refer to a single instance of systemd, some operations are not supported such as starting and stopping daemons.

const (
	SystemMode InstanceMode = iota
	UserMode
	GlobalUserMode
)

type Log

type Log map[string]*json.RawMessage

A Log is a single entry in the systemd journal. In almost all cases, the strings map to a single string value, but as per the manpage for journalctl, under the json format,

Journal entries permit non-unique fields within the same log entry. JSON
does not allow non-unique fields within objects. Due to this, if a
non-unique field is encountered a JSON array is used as field value,
listing all field values as elements.

and this snippet as well,

Fields containing non-printable or non-UTF8 bytes are
encoded as arrays containing the raw bytes individually
formatted as unsigned numbers.

as such, we sometimes get array values which need to be handled differently, so we manually try to decode the json for each message into different types.

func (Log) Message

func (l Log) Message() string

Message of the Log, if any; otherwise, "-".

func (Log) PID

func (l Log) PID() string

PID is the pid of the client pid, if any; otherwise, "-".

func (Log) SID

func (l Log) SID() string

SID is the syslog identifier of the Log, if any; otherwise, "-".

func (Log) Time

func (l Log) Time() (time.Time, error)

Time returns the time the Log was received by the journal.

type Systemd

type Systemd interface {
	// DaemonReload reloads systemd's configuration.
	DaemonReload() error
	// DaemonRexec reexecutes systemd's system manager, should be
	// only necessary to apply manager's configuration like
	// watchdog.
	DaemonReexec() error
	// Enable the given service.
	Enable(service string) error
	// Disable the given service.
	Disable(service string) error
	// Start the given service or services.
	Start(service ...string) error
	// StartNoBlock starts the given service or services non-blocking.
	StartNoBlock(service ...string) error
	// Stop the given service, and wait until it has stopped.
	Stop(service string, timeout time.Duration) error
	// Kill all processes of the unit with the given signal.
	Kill(service, signal, who string) error
	// Restart the service, waiting for it to stop before starting it again.
	Restart(service string, timeout time.Duration) error
	// Reload or restart the service via 'systemctl reload-or-restart'
	ReloadOrRestart(service string) error
	// RestartAll restarts the given service using systemctl restart --all
	RestartAll(service string) error
	// Status fetches the status of given units. Statuses are
	// returned in the same order as unit names passed in
	// argument.
	Status(units ...string) ([]*UnitStatus, error)
	// InactiveEnterTimestamp returns the time that the given unit entered the
	// inactive state as defined by the systemd docs. Specifically, this time is
	// the most recent time in which the unit transitioned from deactivating
	// ("Stopping") to dead ("Stopped"). It may be the zero time if this has
	// never happened during the current boot, since this property is only
	// tracked during the current boot. It specifically does not return a time
	// that is monotonic, so the time returned here may be subject to bugs if
	// there was a discontinuous time jump on the system before or during the
	// unit's transition to inactive.
	// TODO: incorporate this result into Status instead?
	InactiveEnterTimestamp(unit string) (time.Time, error)
	// IsEnabled checks whether the given service is enabled.
	IsEnabled(service string) (bool, error)
	// IsActive checks whether the given service is Active
	IsActive(service string) (bool, error)
	// LogReader returns a reader for the given services' log.
	LogReader(services []string, n int, follow bool) (io.ReadCloser, error)
	// AddMountUnitFile adds/enables/starts a mount unit.
	AddMountUnitFile(name, revision, what, where, fstype string) (string, error)
	// RemoveMountUnitFile unmounts/stops/disables/removes a mount unit.
	RemoveMountUnitFile(baseDir string) error
	// Mask the given service.
	Mask(service string) error
	// Unmask the given service.
	Unmask(service string) error
	// Mount requests a mount of what under where with options.
	Mount(what, where string, options ...string) error
	// Umount requests a mount from what or at where to be unmounted.
	Umount(whatOrWhere string) error
	// CurrentMemoryUsage returns the current memory usage for the specified
	// unit.
	CurrentMemoryUsage(unit string) (quantity.Size, error)
	// CurrentTasksCount returns the number of tasks (processes, threads, kernel
	// threads if enabled, etc) part of the unit, which can be a service or a
	// slice.
	CurrentTasksCount(unit string) (uint64, error)
}

Systemd exposes a minimal interface to manage systemd via the systemctl command.

func New

func New(mode InstanceMode, rep reporter) Systemd

New returns a Systemd that uses the default root directory and omits --root argument when executing systemctl.

func NewEmulationMode

func NewEmulationMode(rootDir string) Systemd

NewEmulationMode returns a Systemd that runs in emulation mode where systemd is not really called, but instead its functions are emulated by other means.

func NewUnderRoot

func NewUnderRoot(rootDir string, mode InstanceMode, rep reporter) Systemd

NewUnderRoot returns a Systemd that operates on the given rootdir.

type Timeout

type Timeout struct {
	// contains filtered or unexported fields
}

Timeout is returned if the systemd action failed to reach the expected state in a reasonable amount of time

func (*Timeout) Error

func (e *Timeout) Error() string

type UnitStatus

type UnitStatus struct {
	Daemon   string
	UnitName string
	Enabled  bool
	Active   bool
	// Installed is false if the queried unit doesn't exist.
	Installed bool
}