hostdb

Documentation

Overview

package hostdb provides a HostDB object that implements the modules.HostDB interface. The blockchain is scanned for host announcements and hosts that are found get added to the host database. The database continually scans the set of hosts it has found and updates who is online.

Index

• Constants
• Variables
• type HostDB
  • func New(cs *consensus.State, g modules.Gateway) (hdb *HostDB, err error)
  • func (hdb *HostDB) ActiveHosts() (activeHosts []modules.HostSettings)
  • func (hdb *HostDB) AllHosts() (allHosts []modules.HostSettings)
  • func (hdb *HostDB) HostDBNotify() <-chan struct{}
  • func (hdb *HostDB) InsertHost(host modules.HostSettings) error
  • func (hdb *HostDB) RandomHosts(count int) (hosts []modules.HostSettings)
  • func (hdb *HostDB) ReceiveConsensusSetUpdate(cc modules.ConsensusChange)
  • func (hdb *HostDB) RemoveHost(addr modules.NetAddress) error

Constants

const (
	DefaultScanSleep = 15 * time.Hour
	MaxScanSleep     = 20 * time.Hour
	MinScanSleep     = 4 * time.Hour

	MaxActiveHosts              = 200
	InactiveHostCheckupQuantity = 100
)

const (
	// Hosts will not be removed if there are fewer than this many hosts.
	// Eventually, this number should be in the low thousands.
	MinHostThreshold = 5
)

Variables

var (
	ErrNilGateway      = errors.New("gateway cannot be nil")
	ErrNilConsensusSet = errors.New("consensus set cannot be nil")
)

var (
	ActiveReliability   = types.NewCurrency64(20)
	InactiveReliability = types.NewCurrency64(10)
	UnreachablePenalty  = types.NewCurrency64(1)
)

var (
	ErrOverweight = errors.New("requested a too-heavy weight")
)

Types

type HostDB

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

The HostDB is a database of potential hosts. It assigns a weight to each host based on their hosting parameters, and then can select hosts at random for uploading files.

func New

func New(cs *consensus.State, g modules.Gateway) (hdb *HostDB, err error)

New returns an empty HostDatabase.

func (*HostDB) ActiveHosts

func (hdb *HostDB) ActiveHosts() (activeHosts []modules.HostSettings)

ActiveHosts returns the hosts that can be randomly selected out of the hostdb.

func (*HostDB) AllHosts

func (hdb *HostDB) AllHosts() (allHosts []modules.HostSettings)

AllHosts returns all of the hosts known to the hostdb, including the inactive ones.

func (*HostDB) HostDBNotify

func (hdb *HostDB) HostDBNotify() <-chan struct{}

HostDBNotify adds a subscriber to the hostdb.

func (*HostDB) InsertHost

func (hdb *HostDB) InsertHost(host modules.HostSettings) error

InsertHost inserts a host into the database.

func (*HostDB) RandomHosts

func (hdb *HostDB) RandomHosts(count int) (hosts []modules.HostSettings)

RandomHosts will pull up to 'num' random hosts from the hostdb. There will be no repeats, but the length of the slice returned may be less than 'num', and may even be 0. The hosts that get returned first have the higher priority.

func (*HostDB) ReceiveConsensusSetUpdate

func (hdb *HostDB) ReceiveConsensusSetUpdate(cc modules.ConsensusChange)

ReceiveConsensusSetUpdate accepts an update from the consensus set which contains new blocks.

func (*HostDB) RemoveHost

func (hdb *HostDB) RemoveHost(addr modules.NetAddress) error

RemoveHost removes a host from the database.