nim-ethers/ethers/providers/jsonrpc/subscriptions.nim
2023-07-03 13:09:09 +02:00

101 lines
3.4 KiB
Nim

import std/tables
import pkg/chronos
import pkg/json_rpc/rpcclient
import ../../basics
import ../../provider
import ./rpccalls
import ./conversions
type
JsonRpcSubscriptions* = ref object of RootObj
client: RpcClient
callbacks: Table[JsonNode, SubscriptionCallback]
JsonRpcSubscription = ref object of Subscription
subscriptions: JsonRpcSubscriptions
id: JsonNode
SubscriptionCallback = proc(id, arguments: JsonNode) {.gcsafe, upraises:[].}
method subscribeBlocks*(subscriptions: JsonRpcSubscriptions,
onBlock: BlockHandler):
Future[JsonRpcSubscription]
{.async, base.} =
raiseAssert "not implemented"
method subscribeLogs*(subscriptions: JsonRpcSubscriptions,
filter: Filter,
onLog: LogHandler):
Future[JsonRpcSubscription]
{.async, base.} =
raiseAssert "not implemented"
method unsubscribe(subscriptions: JsonRpcSubscriptions,
id: JsonNode)
{.async, base.} =
raiseAssert "not implemented"
method unsubscribe(subscription: JsonRpcSubscription) {.async.} =
await subscription.subscriptions.unsubscribe(subscription.id)
proc getCallback(subscriptions: JsonRpcSubscriptions,
id: JsonNode): ?SubscriptionCallback =
try:
if subscriptions.callbacks.hasKey(id):
subscriptions.callbacks[id].some
else:
SubscriptionCallback.none
except Exception:
SubscriptionCallback.none
# Web sockets
type
WebSocketSubscriptions = ref object of JsonRpcSubscriptions
method subscribeBlocks(subscriptions: WebSocketSubscriptions,
onBlock: BlockHandler):
Future[JsonRpcSubscription]
{.async.} =
proc callback(id, arguments: JsonNode) =
if blck =? Block.fromJson(arguments["result"]).catch:
asyncSpawn onBlock(blck)
let id = await subscriptions.client.eth_subscribe("newHeads")
subscriptions.callbacks[id] = callback
return JsonRpcSubscription(subscriptions: subscriptions, id: id)
method subscribeLogs(subscriptions: WebSocketSubscriptions,
filter: Filter,
onLog: LogHandler):
Future[JsonRpcSubscription]
{.async.} =
proc callback(id, arguments: JsonNode) =
if log =? Log.fromJson(arguments["result"]).catch:
onLog(log)
let id = await subscriptions.client.eth_subscribe("logs", filter)
subscriptions.callbacks[id] = callback
return JsonRpcSubscription(subscriptions: subscriptions, id: id)
method unsubscribe(subscriptions: WebSocketSubscriptions,
id: JsonNode)
{.async.} =
subscriptions.callbacks.del(id)
discard await subscriptions.client.eth_unsubscribe(id)
proc new*(_: type JsonRpcSubscriptions,
client: RpcWebSocketClient): JsonRpcSubscriptions =
let subscriptions = WebSocketSubscriptions(client: client)
proc subscriptionHandler(arguments: JsonNode) {.upraises:[].} =
if id =? arguments["subscription"].catch and
callback =? subscriptions.getCallback(id):
callback(id, arguments)
client.setMethodHandler("eth_subscription", subscriptionHandler)
subscriptions
# Polling
type
PollingSubscriptions = ref object of JsonRpcSubscriptions
func new*(_: type JsonRpcSubscriptions,
client: RpcHttpClient): JsonRpcSubscriptions =
PollingSubscriptions(client: client)