leadership

Documentation

Index

• Constants
• func NewLeadershipServiceFn(leadershipMgr leadership.LeadershipManager) ...
• type GetSettingsFn
• type IsLeaderFn
• type LeadershipService
  • func NewLeadershipService(state *state.State, resources *common.Resources, authorizer common.Authorizer, ...) (LeadershipService, error)
• type LeadershipSettingsAccessor
  • func NewLeadershipSettingsAccessor(authorizer common.Authorizer, registerWatcherFn RegisterWatcherFn, ...) *LeadershipSettingsAccessor
  • func (lsa *LeadershipSettingsAccessor) Merge(bulkArgs params.MergeLeadershipSettingsBulkParams) (params.ErrorResults, error)
  • func (lsa *LeadershipSettingsAccessor) Read(bulkArgs params.Entities) (params.GetLeadershipSettingsBulkResults, error)
  • func (lsa *LeadershipSettingsAccessor) WatchLeadershipSettings(arg params.Entities) (params.NotifyWatchResults, error)
• type MergeSettingsChunkFn
• type RegisterWatcherFn

Constants

const (
	// FacadeName is the string-representation of this API used both
	// to register the service, and for the client to resolve the
	// service endpoint.
	FacadeName = "LeadershipService"

	// MinLeaseRequest is the shortest duration for which we will accept
	// a leadership claim.
	MinLeaseRequest = 5 * time.Second

	// MaxLeaseRequest is the longest duration for which we will accept
	// a leadership claim.
	MaxLeaseRequest = 5 * time.Minute
)

Functions

func NewLeadershipServiceFn

func NewLeadershipServiceFn(
	leadershipMgr leadership.LeadershipManager,
) func(*state.State, *common.Resources, common.Authorizer) (LeadershipService, error)

NewLeadershipServiceFn returns a function which can construct a LeadershipService when passed a state, resources, and authorizer. This function signature conforms to Juju's required API server signature.

Types

type GetSettingsFn

type GetSettingsFn func(serviceId string) (map[string]string, error)

GetSettingsFn declares a function-type which will return leadership settings for the given service ID.

type IsLeaderFn

type IsLeaderFn func(serviceId, unitId string) (bool, error)

IsLeaderFn declares a function-type which will return whether the given service-unit-id combination is currently the leader.

type LeadershipService

type LeadershipService interface {
	// ClaimLeadership makes a leadership claim with the given parameters.
	ClaimLeadership(params params.ClaimLeadershipBulkParams) (params.ClaimLeadershipBulkResults, error)
	// ReleaseLeadership makes a call to release leadership for all the
	// parameters passed in.
	ReleaseLeadership(params params.ReleaseLeadershipBulkParams) (params.ReleaseLeadershipBulkResults, error)
	// BlockUntilLeadershipReleased blocks the caller until leadership is
	// released for the given service.
	BlockUntilLeadershipReleased(serviceTag names.ServiceTag) (params.ErrorResult, error)
}

func NewLeadershipService

func NewLeadershipService(
	state *state.State,
	resources *common.Resources,
	authorizer common.Authorizer,
	leadershipMgr leadership.LeadershipManager,
) (LeadershipService, error)

NewLeadershipService constructs a new LeadershipService.

type LeadershipSettingsAccessor

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

LeadershipSettingsAccessor provides a type which can read, write, and watch leadership settings.

func NewLeadershipSettingsAccessor

func NewLeadershipSettingsAccessor(
	authorizer common.Authorizer,
	registerWatcherFn RegisterWatcherFn,
	getSettingsFn GetSettingsFn,
	mergeSettingsChunkFn MergeSettingsChunkFn,
	isLeaderFn IsLeaderFn,
) *LeadershipSettingsAccessor

NewLeadershipSettingsAccessor creates a new LeadershipSettingsAccessor.

func (*LeadershipSettingsAccessor) Merge

func (lsa *LeadershipSettingsAccessor) Merge(bulkArgs params.MergeLeadershipSettingsBulkParams) (params.ErrorResults, error)

Merge merges in the provided leadership settings. Only leaders for the given service may perform this operation.

func (*LeadershipSettingsAccessor) Read

func (lsa *LeadershipSettingsAccessor) Read(bulkArgs params.Entities) (params.GetLeadershipSettingsBulkResults, error)

Read reads leadership settings for the provided service ID. Any unit of the service may perform this operation.

func (*LeadershipSettingsAccessor) WatchLeadershipSettings

func (lsa *LeadershipSettingsAccessor) WatchLeadershipSettings(arg params.Entities) (params.NotifyWatchResults, error)

WatchLeadershipSettings will block the caller until leadership settings for the given service ID change.

type MergeSettingsChunkFn

type MergeSettingsChunkFn func(serviceId string, settings map[string]string) error

MergeSettingsChunk declares a function-type which will write the provided settings chunk into the greater leadership settings for the provided service ID.

type RegisterWatcherFn

type RegisterWatcherFn func(serviceId string) (watcherId string, _ error)

SettingsChangeNotifierFn declares a function-type which will return a channel that can be blocked on to be notified of setting changes for the provided document key.