machine

type HTTPClient interface {
	Do(req *http.Request) (*http.Response, error)
}

type Logger interface {
	Debugf(string, ...interface{})
	Warningf(string, ...interface{})
	Criticalf(string, ...interface{})
	Tracef(string, ...interface{})
}

type MachineStartupConfig struct {
	APICallerName  string
	MachineStartup func(api.Connection, Logger) error
	Logger         Logger
}

type ManifoldsConfig struct {

	// AgentName is the name of the machine agent, like "machine-12".
	// This will never change during the execution of an agent, and
	// is used to provide this as config into a worker rather than
	// making the worker get it from the agent worker itself.
	AgentName string

	// Agent contains the agent that will be wrapped and made available to
	// its dependencies via a dependency.Engine.
	Agent coreagent.Agent

	// AgentConfigChanged is set whenever the machine agent's config
	// is updated.
	AgentConfigChanged *voyeur.Value

	// RootDir is the root directory that any worker that needs to
	// access local filesystems should use as a base. In actual use it
	// will be "" but it may be overridden in tests.
	RootDir string

	// PreviousAgentVersion passes through the version the machine
	// agent was running before the current restart.
	PreviousAgentVersion version.Number

	// UpgradeStepsLock is passed to the upgrade steps gate to
	// coordinate workers that shouldn't do anything until the
	// upgrade-steps worker is done.
	UpgradeStepsLock gate.Lock

	// UpgradeCheckLock is passed to the upgrade check gate to
	// coordinate workers that shouldn't do anything until the
	// upgrader worker completes it's first check.
	UpgradeCheckLock gate.Lock

	// MachineStartup is passed to the machine manifold. It does
	// machine setup work which relies on an API connection.
	MachineStartup func(api.Connection, Logger) error

	// PreUpgradeSteps is a function that is used by the upgradesteps
	// worker to ensure that conditions are OK for an upgrade to
	// proceed.
	PreUpgradeSteps upgrades.PreUpgradeStepsFunc

	// LogSource defines the channel type used to send log message
	// structs within the machine agent.
	LogSource logsender.LogRecordCh

	// NewDeployContext gives the tests the opportunity to create a
	// deployer.Context that can be used for testing.
	NewDeployContext func(deployer.ContextConfig) (deployer.Context, error)

	// Clock supplies timekeeping services to various workers.
	Clock clock.Clock

	// ValidateMigration is called by the migrationminion during the
	// migration process to check that the agent will be ok when
	// connected to the new target controller.
	ValidateMigration func(base.APICaller) error

	// PrometheusRegisterer is a prometheus.Registerer that may be used
	// by workers to register Prometheus metric collectors.
	PrometheusRegisterer prometheus.Registerer

	// LocalHub is a simple pubsub that is used for internal agent
	// messaging only. This is used for interactions between workers
	// and the introspection worker.
	LocalHub *pubsub.SimpleHub

	// UpdateLoggerConfig is a function that will save the specified
	// config value as the logging config in the agent.conf file.
	UpdateLoggerConfig func(string) error

	// NewAgentStatusSetter provides upgradesteps.StatusSetter.
	NewAgentStatusSetter func(apiConn api.Connection) (upgradesteps.StatusSetter, error)

	// ControllerLeaseDuration defines for how long this agent will ask
	// for controller administration rights.
	ControllerLeaseDuration time.Duration

	// TransactionPruneInterval defines how frequently mgo/txn transactions
	// are pruned from the database.
	TransactionPruneInterval time.Duration

	// SetStatePool is used by the state worker for informing the agent of
	// the StatePool that it creates, so we can pass it to the introspection
	// worker running outside of the dependency engine.
	SetStatePool func(*state.StatePool)

	// RegisterIntrospectionHTTPHandlers is a function that calls the
	// supplied function to register introspection HTTP handlers. The
	// function will be passed a path and a handler; the function may
	// alter the path as it sees fit, e.g. by adding a prefix.
	RegisterIntrospectionHTTPHandlers func(func(path string, _ http.Handler))

	// MachineLock is a central source for acquiring the machine lock.
	// This is used by a number of workers to ensure serialisation of actions
	// across the machine.
	MachineLock machinelock.Lock

	// MuxShutdownWait is the maximum time the http-server worker will wait
	// for all mux clients to gracefully terminate before the http-worker
	// exits regardless.
	MuxShutdownWait time.Duration

	// NewContainerBrokerFunc is a function opens a CAAS provider.
	NewContainerBrokerFunc caas.NewContainerBrokerFunc

	// NewBrokerFunc is a function opens a instance broker (LXD/KVM)
	NewBrokerFunc containerbroker.NewBrokerFunc

	// IsCaasConfig is true if this config is for a caas agent.
	IsCaasConfig bool

	// UnitEngineConfig is used by the deployer to initialize the unit's
	// dependency engine when running in the nested context.
	UnitEngineConfig func() dependency.EngineConfig

	// SetupLogging is used by the deployer to initialize the logging
	// context for the unit.
	SetupLogging func(*loggo.Context, coreagent.Config)

	// DependencyEngineMetrics creates a set of metrics for a model, so it's
	// possible to know the lifecycle of the workers in the dependency engine.
	DependencyEngineMetrics modelworkermanager.ModelMetrics

	// CharmhubHTTPClient is the HTTP client used for Charmhub API requests.
	CharmhubHTTPClient HTTPClient
}