nim-libp2p-experimental/libp2p/peerstore.nim

172 lines
4.8 KiB
Nim

## Nim-LibP2P
## Copyright (c) 2021 Status Research & Development GmbH
## Licensed under either of
## * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE))
## * MIT license ([LICENSE-MIT](LICENSE-MIT))
## at your option.
## This file may not be copied, modified, or distributed except according to
## those terms.
{.push raises: [Defect].}
import
std/[tables, sets, sequtils, options],
./crypto/crypto,
./peerid, ./peerinfo,
./multiaddress
type
#################
# Handler types #
#################
PeerBookChangeHandler*[T] = proc(peerId: PeerID, entry: T)
AddrChangeHandler* = PeerBookChangeHandler[HashSet[MultiAddress]]
ProtoChangeHandler* = PeerBookChangeHandler[HashSet[string]]
KeyChangeHandler* = PeerBookChangeHandler[PublicKey]
#########
# Books #
#########
# Each book contains a book (map) and event handler(s)
PeerBook*[T] = object of RootObj
book*: Table[PeerID, T]
changeHandlers: seq[PeerBookChangeHandler[T]]
SetPeerBook*[T] = object of PeerBook[HashSet[T]]
AddressBook* = object of SetPeerBook[MultiAddress]
ProtoBook* = object of SetPeerBook[string]
KeyBook* = object of PeerBook[PublicKey]
####################
# Peer store types #
####################
PeerStore* = ref object
addressBook*: AddressBook
protoBook*: ProtoBook
keyBook*: KeyBook
StoredInfo* = object
# Collates stored info about a peer
peerId*: PeerID
addrs*: HashSet[MultiAddress]
protos*: HashSet[string]
publicKey*: PublicKey
## Constructs a new PeerStore with metadata of type M
proc new*(T: type PeerStore): PeerStore =
var p: PeerStore
new(p)
return p
#########################
# Generic Peer Book API #
#########################
proc get*[T](peerBook: PeerBook[T],
peerId: PeerID): T =
## Get all the known metadata of a provided peer.
peerBook.book.getOrDefault(peerId)
proc set*[T](peerBook: var PeerBook[T],
peerId: PeerID,
entry: T) =
## Set metadata for a given peerId. This will replace any
## previously stored metadata.
peerBook.book[peerId] = entry
# Notify clients
for handler in peerBook.changeHandlers:
handler(peerId, peerBook.get(peerId))
proc delete*[T](peerBook: var PeerBook[T],
peerId: PeerID): bool =
## Delete the provided peer from the book.
if not peerBook.book.hasKey(peerId):
return false
else:
peerBook.book.del(peerId)
return true
################
# Set Book API #
################
proc add*[T](
peerBook: var SetPeerBook[T],
peerId: PeerID,
entry: T) =
## Add entry to a given peer. If the peer is not known,
## it will be set with the provided entry.
peerBook.book.mgetOrPut(peerId,
initHashSet[T]()).incl(entry)
# Notify clients
for handler in peerBook.changeHandlers:
handler(peerId, peerBook.get(peerId))
##################
# Peer Store API #
##################
proc addHandlers*(peerStore: PeerStore,
addrChangeHandler: AddrChangeHandler,
protoChangeHandler: ProtoChangeHandler,
keyChangeHandler: KeyChangeHandler) =
## Register event handlers to notify clients of changes in the peer store
peerStore.addressBook.changeHandlers.add(addrChangeHandler)
peerStore.protoBook.changeHandlers.add(protoChangeHandler)
peerStore.keyBook.changeHandlers.add(keyChangeHandler)
proc delete*(peerStore: PeerStore,
peerId: PeerID): bool =
## Delete the provided peer from every book.
peerStore.addressBook.delete(peerId) and
peerStore.protoBook.delete(peerId) and
peerStore.keyBook.delete(peerId)
proc get*(peerStore: PeerStore,
peerId: PeerID): StoredInfo =
## Get the stored information of a given peer.
StoredInfo(
peerId: peerId,
addrs: peerStore.addressBook.get(peerId),
protos: peerStore.protoBook.get(peerId),
publicKey: peerStore.keyBook.get(peerId)
)
proc update*(peerStore: PeerStore, peerInfo: PeerInfo) =
for address in peerInfo.addrs:
peerStore.addressBook.add(peerInfo.peerId, address)
for proto in peerInfo.protocols:
peerStore.protoBook.add(peerInfo.peerId, proto)
let pKey = peerInfo.publicKey()
if pKey.isSome:
peerStore.keyBook.set(peerInfo.peerId, pKey.get())
proc replace*(peerStore: PeerStore, peerInfo: PeerInfo) =
discard peerStore.addressBook.delete(peerInfo.peerId)
discard peerStore.protoBook.delete(peerInfo.peerId)
discard peerStore.keyBook.delete(peerInfo.peerId)
peerStore.update(peerInfo)
proc peers*(peerStore: PeerStore): seq[StoredInfo] =
## Get all the stored information of every peer.
let allKeys = concat(toSeq(keys(peerStore.addressBook.book)),
toSeq(keys(peerStore.protoBook.book)),
toSeq(keys(peerStore.keyBook.book))).toHashSet()
return allKeys.mapIt(peerStore.get(it))