agent

type APIHostPortsSetter struct {
	Agent
}

type Agent interface {

	// CurrentConfig returns a copy of the agent's configuration. No
	// guarantees regarding ongoing correctness are made.
	CurrentConfig() Config

	// ChangeConfig allows clients to change the agent's configuration
	// by supplying a callback that applies the changes.
	ChangeConfig(ConfigMutator) error
}

type AgentConfigParams struct {
	Paths                  Paths
	Jobs                   []model.MachineJob
	UpgradedToVersion      version.Number
	Tag                    names.Tag
	Password               string
	Nonce                  string
	Controller             names.ControllerTag
	Model                  names.ModelTag
	APIAddresses           []string
	CACert                 string
	Values                 map[string]string
	MongoMemoryProfile     mongo.MemoryProfile
	JujuDBSnapChannel      string
	AgentLogfileMaxSizeMB  int
	AgentLogfileMaxBackups int
	QueryTracingEnabled    bool
	QueryTracingThreshold  time.Duration
	DqlitePort             int
}

type Config interface {
	// DataDir returns the data directory. Each agent has a subdirectory
	// containing the configuration files.
	DataDir() string

	// TransientDataDir returns the directory where this agent should store
	// any data that is not expected to survive a reboot.
	TransientDataDir() string

	// LogDir returns the log directory. All logs from all agents on
	// the machine are written to this directory.
	LogDir() string

	// SystemIdentityPath returns the path of the file where the environment
	// SSH key is kept.
	SystemIdentityPath() string

	// Jobs returns a list of MachineJobs that need to run.
	Jobs() []model.MachineJob

	// Tag returns the tag of the entity on whose behalf the state connection
	// will be made.
	Tag() names.Tag

	// Dir returns the agent's directory.
	Dir() string

	// Nonce returns the nonce saved when the machine was provisioned
	// TODO: make this one of the key/value pairs.
	Nonce() string

	// CACert returns the CA certificate that is used to validate the state or
	// API server's certificate.
	CACert() string

	// APIAddresses returns the addresses needed to connect to the api server
	APIAddresses() ([]string, error)

	// WriteCommands returns shell commands to write the agent configuration.
	// It returns an error if the configuration does not have all the right
	// elements.
	WriteCommands(renderer shell.Renderer) ([]string, error)

	// StateServingInfo returns the details needed to run
	// a controller and reports whether those details
	// are available
	StateServingInfo() (controller.StateServingInfo, bool)

	// APIInfo returns details for connecting to the API server and
	// reports whether the details are available.
	APIInfo() (*api.Info, bool)

	// MongoInfo returns details for connecting to the controller's mongo
	// database and reports whether those details are available
	MongoInfo() (*mongo.MongoInfo, bool)

	// OldPassword returns the fallback password when connecting to the
	// API server.
	OldPassword() string

	// UpgradedToVersion returns the version for which all upgrade steps have been
	// successfully run, which is also the same as the initially deployed version.
	UpgradedToVersion() version.Number

	// LoggingConfig returns the logging config for this agent. Initially this
	// value is empty, but as the agent gets notified of model agent config
	// changes this value is saved.
	LoggingConfig() string

	// Value returns the value associated with the key, or an empty string if
	// the key is not found.
	Value(key string) string

	// Model returns the tag for the model that the agent belongs to.
	Model() names.ModelTag

	// Controller returns the tag for the controller that the agent belongs to.
	Controller() names.ControllerTag

	// MetricsSpoolDir returns the spool directory where workloads store
	// collected metrics.
	MetricsSpoolDir() string

	// MongoMemoryProfile returns the profile to be used when setting
	// mongo memory usage.
	MongoMemoryProfile() mongo.MemoryProfile

	// JujuDBSnapChannel returns the channel for installing mongo snaps in
	// focal or later.
	JujuDBSnapChannel() string

	// AgentLogfileMaxSizeMB returns the maximum file size in MB of each
	// agent/controller log file.
	AgentLogfileMaxSizeMB() int

	// AgentLogfileMaxBackups returns the number of old agent/controller log
	// files to keep (compressed).
	AgentLogfileMaxBackups() int

	// QueryTracingEnabled returns whether query tracing is enabled.
	QueryTracingEnabled() bool

	// QueryTracingThreshold returns the threshold for query tracing. The
	// lower the threshold, the more queries will be output. A value of 0
	// means all queries will be output.
	QueryTracingThreshold() time.Duration

	// DqlitePort returns the port that should be used by Dqlite. This should
	// only be set during testing.
	DqlitePort() (int, bool)
}

type ConfigMutator func(ConfigSetter) error

type ConfigRenderer interface {
	// Render generates the agent configuration
	// as a byte array.
	Render() ([]byte, error)
}

type ConfigSetter interface {
	Config
	// contains filtered or unexported methods
}

type ConfigSetterWriter interface {
	Config

	ConfigWriter
	// contains filtered or unexported methods
}

type ConfigWriter interface {
	ConfigRenderer

	// Write writes the agent configuration.
	Write() error
}

type Paths struct {
	// DataDir is the data directory where each agent has a subdirectory
	// containing the configuration files.
	DataDir string
	// TransientDataDir is a directory where each agent can store data that
	// is not expected to survive a reboot.
	TransientDataDir string
	// LogDir is the log directory where all logs from all agents on
	// the machine are written.
	LogDir string
	// MetricsSpoolDir is the spool directory where workloads store
	// collected metrics.
	MetricsSpoolDir string
	// ConfDir is the directory where all  config file for
	// Juju agents are stored.
	ConfDir string
}