status-go/vendor/github.com/libp2p/go-libp2p-peerstore/addr/addrsrcs.go

71 lines
1.7 KiB
Go

// Package addr provides utility functions to handle peer addresses.
package addr
import (
ma "github.com/multiformats/go-multiaddr"
)
// AddrSource is a source of addresses. It allows clients to retrieve
// a set of addresses at a last possible moment in time. It is used
// to query a set of addresses that may change over time, as a result
// of the network changing interfaces or mappings.
type Source interface {
Addrs() []ma.Multiaddr
}
// CombineSources returns a new AddrSource which is the
// concatenation of all input AddrSources:
//
// combined := CombinedSources(a, b)
// combined.Addrs() // append(a.Addrs(), b.Addrs()...)
//
func CombineSources(srcs ...Source) Source {
return combinedAS(srcs)
}
type combinedAS []Source
func (cas combinedAS) Addrs() []ma.Multiaddr {
var addrs []ma.Multiaddr
for _, s := range cas {
addrs = append(addrs, s.Addrs()...)
}
return addrs
}
// UniqueSource returns a new AddrSource which omits duplicate
// addresses from the inputs:
//
// unique := UniqueSource(a, b)
// unique.Addrs() // append(a.Addrs(), b.Addrs()...)
// // but only adds each addr once.
//
func UniqueSource(srcs ...Source) Source {
return uniqueAS(srcs)
}
type uniqueAS []Source
func (uas uniqueAS) Addrs() []ma.Multiaddr {
seen := make(map[string]struct{})
var addrs []ma.Multiaddr
for _, s := range uas {
for _, a := range s.Addrs() {
s := a.String()
if _, found := seen[s]; !found {
addrs = append(addrs, a)
seen[s] = struct{}{}
}
}
}
return addrs
}
// Slice is a simple slice of addresses that implements
// the AddrSource interface.
type Slice []ma.Multiaddr
func (as Slice) Addrs() []ma.Multiaddr {
return as
}