go-libp2p-core/event/addrs.go

83 lines
3.3 KiB
Go

package event
import (
"github.com/libp2p/go-libp2p-core/record"
ma "github.com/multiformats/go-multiaddr"
)
// AddrAction represents an action taken on one of a Host's listen addresses.
// It is used to add context to address change events in EvtLocalAddressesUpdated.
type AddrAction int
const (
// Unknown means that the event producer was unable to determine why the address
// is in the current state.
Unknown AddrAction = iota
// Added means that the address is new and was not present prior to the event.
Added
// Maintained means that the address was not altered between the current and
// previous states.
Maintained
// Removed means that the address was removed from the Host.
Removed
)
// UpdatedAddress is used in the EvtLocalAddressesUpdated event to convey
// address change information.
type UpdatedAddress struct {
// Address contains the address that was updated.
Address ma.Multiaddr
// Action indicates what action was taken on the address during the
// event. May be Unknown if the event producer cannot produce diffs.
Action AddrAction
}
// EvtLocalAddressesUpdated should be emitted when the set of listen addresses for
// the local host changes. This may happen for a number of reasons. For example,
// we may have opened a new relay connection, established a new NAT mapping via
// UPnP, or been informed of our observed address by another peer.
//
// EvtLocalAddressesUpdated contains a snapshot of the current listen addresses,
// and may also contain a diff between the current state and the previous state.
// If the event producer is capable of creating a diff, the Diffs field will be
// true, and event consumers can inspect the Action field of each UpdatedAddress
// to see how each address was modified.
//
// For example, the Action will tell you whether an address in
// the Current list was Added by the event producer, or was Maintained without
// changes. Addresses that were removed from the Host will have the AddrAction
// of Removed, and will be in the Removed list.
//
// If the event producer is not capable or producing diffs, the Diffs field will
// be false, the Removed list will always be empty, and the Action for each
// UpdatedAddress in the Current list will be Unknown.
//
// In addition to the above, EvtLocalAddressesUpdated also contains the updated peer.PeerRecord
// for the Current set of listen addresses, wrapped in a record.Envelope and signed by the Host's private key.
// This record can be shared with other peers to inform them of what we believe are our diallable addresses
// a secure and authenticated way.
type EvtLocalAddressesUpdated struct {
// Diffs indicates whether this event contains a diff of the Host's previous
// address set.
Diffs bool
// Current contains all current listen addresses for the Host.
// If Diffs == true, the Action field of each UpdatedAddress will tell
// you whether an address was Added, or was Maintained from the previous
// state.
Current []UpdatedAddress
// Removed contains addresses that were removed from the Host.
// This field is only set when Diffs == true.
Removed []UpdatedAddress
// SignedPeerRecord contains our own updated peer.PeerRecord, listing the addresses enumerated in Current.
// wrapped in a record.Envelope and signed by the Host's private key.
SignedPeerRecord *record.Envelope
}