agent

Documentation

Overview

agent contains jujud's machine agent.

Index

• Variables
• func DefaultIntrospectionSocketName(entityTag names.Tag) string
• func MachineAgentFactoryFn(agentConfWriter AgentConfigWriter, bufferedLogger *logsender.BufferedLogWriter, ...) func(string) (*MachineAgent, error)
• func NewMachineAgentCmd(ctx *cmd.Context, machineAgentFactory func(string) (*MachineAgent, error), ...) cmd.Command
• func NewModelStorageDataSource(stor storage.Storage, priority int, requireSigned bool) simplestreams.DataSource
• type AgentConf
  • func NewAgentConf(dataDir string) AgentConf
• type AgentConfigWriter
• type AgentInitializer
• type MachineAgent
  • func NewMachineAgent(machineId string, agentConfWriter AgentConfigWriter, ...) (*MachineAgent, error)
  • func (a *MachineAgent) BeginRestore() error
  • func (a *MachineAgent) ChangeConfig(mutate agent.ConfigMutator) error
  • func (a *MachineAgent) EndRestore()
  • func (a *MachineAgent) IsRestorePreparing() bool
  • func (a *MachineAgent) IsRestoreRunning() bool
  • func (a *MachineAgent) PrepareRestore() error
  • func (a *MachineAgent) Restart() error
  • func (a *MachineAgent) Run(*cmd.Context) error
  • func (a *MachineAgent) Stop() error
  • func (a *MachineAgent) Tag() names.Tag
  • func (a *MachineAgent) Wait() error
  • func (a *MachineAgent) WorkersStarted() <-chan struct{}
• type MongoSessioner
• type UnitAgent
  • func NewUnitAgent(ctx *cmd.Context, bufferedLogger *logsender.BufferedLogWriter) (*UnitAgent, error)
  • func (a *UnitAgent) APIWorkers() (worker.Worker, error)
  • func (a *UnitAgent) ChangeConfig(mutate agent.ConfigMutator) error
  • func (a *UnitAgent) Info() *cmd.Info
  • func (a *UnitAgent) Init(args []string) error
  • func (a *UnitAgent) Run(ctx *cmd.Context) error
  • func (a *UnitAgent) SetFlags(f *gnuflag.FlagSet)
  • func (a *UnitAgent) Stop() error
  • func (a *UnitAgent) Tag() names.Tag

Variables

var ProductionMongoWriteConcern = true

Variable to override in tests, default is true

Functions

func DefaultIntrospectionSocketName

func DefaultIntrospectionSocketName(entityTag names.Tag) string

DefaultIntrospectionSocketName returns the socket name to use for the abstract domain socket that the introspection worker serves requests over.

func MachineAgentFactoryFn

func MachineAgentFactoryFn(
	agentConfWriter AgentConfigWriter,
	bufferedLogger *logsender.BufferedLogWriter,
	newIntrospectionSocketName func(names.Tag) string,
	preUpgradeSteps upgrades.PreUpgradeStepsFunc,
	rootDir string,
) func(string) (*MachineAgent, error)

MachineAgentFactoryFn returns a function which instantiates a MachineAgent given a machineId.

func NewMachineAgentCmd

func NewMachineAgentCmd(
	ctx *cmd.Context,
	machineAgentFactory func(string) (*MachineAgent, error),
	agentInitializer AgentInitializer,
	configFetcher AgentConfigWriter,
) cmd.Command

NewMachineAgentCmd creates a Command which handles parsing command-line arguments and instantiating and running a MachineAgent.

func NewModelStorageDataSource

func NewModelStorageDataSource(stor storage.Storage, priority int, requireSigned bool) simplestreams.DataSource

NewModelStorageDataSource returns a new datasource that retrieves metadata from environment storage.

Types

type AgentConf

type AgentConf interface {

	// AddFlags injects common agent flags into f.
	AddFlags(f *gnuflag.FlagSet)

	// CheckArgs reports whether the given args are valid for this agent.
	CheckArgs(args []string) error

	// DataDir returns the directory where this agent should store its data.
	DataDir() string

	// ReadConfig reads the agent's config from its config file.
	ReadConfig(tag string) error

	// CurrentConfig returns the agent config for this agent.
	CurrentConfig() agent.Config

	// ChangeConfig modifies this configuration using the given mutator.
	ChangeConfig(change agent.ConfigMutator) error
}

AgentConf is a terribly confused interface.

Parts of it are a mixin for cmd.Command implementations; others are a mixin for agent.Agent implementations; others bridge the two. We should be aiming to separate the cmd responsibilities from the agent responsibilities.

func NewAgentConf

func NewAgentConf(dataDir string) AgentConf

NewAgentConf returns a new value that satisfies AgentConf

type AgentConfigWriter

type AgentConfigWriter interface {
	// ReadConfig reads the config for the given tag from disk.
	ReadConfig(tag string) error
	// ChangeConfig executes the given agent.ConfigMutator in a
	// thread-safe context.
	ChangeConfig(agent.ConfigMutator) error
	// CurrentConfig returns a copy of the in-memory agent config.
	CurrentConfig() agent.Config
}

AgentConfigWriter encapsulates disk I/O operations with the agent config.

type AgentInitializer

type AgentInitializer interface {
	AddFlags(*gnuflag.FlagSet)
	CheckArgs([]string) error
}

AgentInitializer handles initializing a type for use as a Jujud agent.

type MachineAgent

type MachineAgent struct {
	AgentConfigWriter
	// contains filtered or unexported fields
}

MachineAgent is responsible for tying together all functionality needed to orchestrate a Jujud instance which controls a machine.

func NewMachineAgent

func NewMachineAgent(
	machineId string,
	agentConfWriter AgentConfigWriter,
	bufferedLogger *logsender.BufferedLogWriter,
	runner *worker.Runner,
	loopDeviceManager looputil.LoopDeviceManager,
	newIntrospectionSocketName func(names.Tag) string,
	preUpgradeSteps upgrades.PreUpgradeStepsFunc,
	rootDir string,
) (*MachineAgent, error)

NewMachineAgent instantiates a new MachineAgent.

func (*MachineAgent) BeginRestore

func (a *MachineAgent) BeginRestore() error

BeginRestore will flag the agent to disallow all commands since restore should be running and therefore making changes that would override anything done.

func (*MachineAgent) ChangeConfig

func (a *MachineAgent) ChangeConfig(mutate agent.ConfigMutator) error

func (*MachineAgent) EndRestore

func (a *MachineAgent) EndRestore()

EndRestore will flag the agent to allow all commands This being invoked means that restore process failed since success restarts the agent.

func (*MachineAgent) IsRestorePreparing

func (a *MachineAgent) IsRestorePreparing() bool

IsRestorePreparing returns bool representing if we are in restore mode but not running restore.

func (*MachineAgent) IsRestoreRunning

func (a *MachineAgent) IsRestoreRunning() bool

IsRestoreRunning returns bool representing if we are in restore mode and running the actual restore process.

func (*MachineAgent) PrepareRestore

func (a *MachineAgent) PrepareRestore() error

PrepareRestore will flag the agent to allow only a limited set of commands defined in "github.com/juju/juju/apiserver".allowedMethodsAboutToRestore the most noteworthy is: Backups.Restore: this will ensure that we can do all the file movements required for restore and no one will do changes while we do that. it will return error if the machine is already in this state.

func (*MachineAgent) Restart

func (a *MachineAgent) Restart() error

Restart restarts the agent's service.

func (*MachineAgent) Run

func (a *MachineAgent) Run(*cmd.Context) error

Run runs a machine agent.

func (*MachineAgent) Stop

func (a *MachineAgent) Stop() error

Stop stops the machine agent.

func (*MachineAgent) Tag

func (a *MachineAgent) Tag() names.Tag

func (*MachineAgent) Wait

func (a *MachineAgent) Wait() error

Wait waits for the machine agent to finish.

func (*MachineAgent) WorkersStarted

func (a *MachineAgent) WorkersStarted() <-chan struct{}

WorkersStarted returns a channel that's closed once all top level workers have been started. This is provided for testing purposes.

type MongoSessioner

type MongoSessioner interface {
	MongoSession() *mgo.Session
}

type UnitAgent

type UnitAgent struct {
	cmd.CommandBase

	AgentConf

	UnitName string
	// contains filtered or unexported fields
}

UnitAgent is a cmd.Command responsible for running a unit agent.

func NewUnitAgent

func NewUnitAgent(ctx *cmd.Context, bufferedLogger *logsender.BufferedLogWriter) (*UnitAgent, error)

NewUnitAgent creates a new UnitAgent value properly initialized.

func (*UnitAgent) APIWorkers

func (a *UnitAgent) APIWorkers() (worker.Worker, error)

APIWorkers returns a dependency.Engine running the unit agent's responsibilities.

func (*UnitAgent) ChangeConfig

func (a *UnitAgent) ChangeConfig(mutate agent.ConfigMutator) error

func (*UnitAgent) Info

func (a *UnitAgent) Info() *cmd.Info

Info returns usage information for the command.

func (*UnitAgent) Init

func (a *UnitAgent) Init(args []string) error

Init initializes the command for running.

func (*UnitAgent) Run

func (a *UnitAgent) Run(ctx *cmd.Context) error

Run runs a unit agent.

func (*UnitAgent) SetFlags

func (a *UnitAgent) SetFlags(f *gnuflag.FlagSet)

func (*UnitAgent) Stop

func (a *UnitAgent) Stop() error

Stop stops the unit agent.

func (*UnitAgent) Tag

func (a *UnitAgent) Tag() names.Tag