hosttree

Documentation

Index

• Constants
• type Filter
  • func NewFilter(resolver modules.Resolver) *Filter
  • func (af *Filter) Add(host modules.NetAddress)
  • func (af *Filter) Filtered(host modules.NetAddress) bool
  • func (af *Filter) Reset()
• type HostTree
  • func New(wf WeightFunc, resolver modules.Resolver) *HostTree
  • func (ht *HostTree) All() []modules.HostDBEntry
  • func (ht *HostTree) Insert(hdbe modules.HostDBEntry) error
  • func (ht *HostTree) Modify(hdbe modules.HostDBEntry) error
  • func (ht *HostTree) Remove(pk types.SiaPublicKey) error
  • func (ht *HostTree) Select(spk types.SiaPublicKey) (modules.HostDBEntry, bool)
  • func (ht *HostTree) SelectRandom(n int, blacklist, addressBlacklist []types.SiaPublicKey) []modules.HostDBEntry
  • func (ht *HostTree) SetWeightFunction(wf WeightFunc) error
• type WeightFunc

Constants

const (
	// IPv4FilterRange is the number of bits within an IP address (starting
	// from the left) which have to be unique for the host not to be filtered.
	IPv4FilterRange = 24
	// IPv6FilterRange is the number of bits within an IP address (starting
	// from the left) which have to be unique for the host not to be filtered.
	IPv6FilterRange = 54
)

Types

type Filter

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

Filter filters host addresses which belong to the same subnet to avoid selecting hosts from the same region.

func NewFilter

func NewFilter(resolver modules.Resolver) *Filter

NewFilter creates a new addressFilter object.

func (*Filter) Add

func (af *Filter) Add(host modules.NetAddress)

Add adds a host to the filter. This will resolve the hostname into one or more IP addresses, extract the subnets used by those addresses and add the subnets to the filter. Add doesn't return an error, but if the addresses of a host can't be resolved it will be handled as if the host had no addresses associated with it.

func (*Filter) Filtered

func (af *Filter) Filtered(host modules.NetAddress) bool

Filtered checks if a host uses a subnet that is already in use by a host that was previously added to the filter. If it is in use, or if the host is associated with 2 addresses of the same type (e.g. IPv4 and IPv4) or if it is associated with more than 2 addresses, Filtered will return 'true'.

func (*Filter) Reset

func (af *Filter) Reset()

Reset clears the filter's contents.

type HostTree

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

HostTree is used to store and select host database entries. Each HostTree is initialized with a weighting func that is able to assign a weight to each entry. The entries can then be selected at random, weighted by the weight func.

func New

func New(wf WeightFunc, resolver modules.Resolver) *HostTree

New creates a new HostTree given a weight function and a resolver for hostnames.

func (*HostTree) All

func (ht *HostTree) All() []modules.HostDBEntry

All returns all of the hosts in the host tree, sorted by weight.

func (*HostTree) Insert

func (ht *HostTree) Insert(hdbe modules.HostDBEntry) error

Insert inserts the entry provided to `entry` into the host tree. Insert will return an error if the input host already exists.

func (*HostTree) Modify

func (ht *HostTree) Modify(hdbe modules.HostDBEntry) error

Modify updates a host entry at the given public key, replacing the old entry with the entry provided by `newEntry`.

func (*HostTree) Remove

func (ht *HostTree) Remove(pk types.SiaPublicKey) error

Remove removes the host with the public key provided by `pk`.

func (*HostTree) Select

func (ht *HostTree) Select(spk types.SiaPublicKey) (modules.HostDBEntry, bool)

Select returns the host with the provided public key, should the host exist.

func (*HostTree) SelectRandom

func (ht *HostTree) SelectRandom(n int, blacklist, addressBlacklist []types.SiaPublicKey) []modules.HostDBEntry

SelectRandom grabs a random n hosts from the tree. There will be no repeats, but the length of the slice returned may be less than n, and may even be zero. The hosts that are returned first have the higher priority. Hosts passed to 'blacklist' will not be considered; pass `nil` if no blacklist is desired. 'addressBlacklist' is similar to 'blacklist' but instead of not considering the hosts in the list, hosts that use the same IP subnet as those hosts will be ignored. In most cases those blacklists contain the same elements but sometimes it is useful to block a host without blocking its IP range.

func (*HostTree) SetWeightFunction

func (ht *HostTree) SetWeightFunction(wf WeightFunc) error

SetWeightFunction resets the HostTree and assigns it a new weight function. This resets the tree and reinserts all the hosts.

type WeightFunc

type WeightFunc func(modules.HostDBEntry) types.Currency

WeightFunc is a function used to weight a given HostDBEntry in the tree.