nim-ethers/testmodule/providers/jsonrpc/testJsonRpcSubscriptions.nim

import std/json
import std/sequtils
import pkg/asynctest
import pkg/serde
import pkg/json_rpc/rpcclient
import pkg/json_rpc/rpcserver
import ethers/provider
import ethers/providers/jsonrpc/subscriptions

import ../../examples
import ./rpc_mock

suite "JsonRpcSubscriptions":

  test "can be instantiated with an http client":
    let client = newRpcHttpClient()
    let subscriptions = JsonRpcSubscriptions.new(client)
    check not isNil subscriptions

  test "can be instantiated with a websocket client":
    let client = newRpcWebSocketClient()
    let subscriptions = JsonRpcSubscriptions.new(client)
    check not isNil subscriptions

template subscriptionTests(subscriptions, client) =

  test "subscribes to new blocks":
    var latestBlock: Block
    proc callback(blck: Block) =
      latestBlock = blck
    let subscription = await subscriptions.subscribeBlocks(callback)
    discard await client.call("evm_mine", newJArray())
    check eventually latestBlock.number.isSome
    check latestBlock.hash.isSome
    check latestBlock.timestamp > 0.u256
    await subscriptions.unsubscribe(subscription)

  test "stops listening to new blocks when unsubscribed":
    var count = 0
    proc callback(blck: Block) =
      inc count
    let subscription = await subscriptions.subscribeBlocks(callback)
    discard await client.call("evm_mine", newJArray())
    check eventually count > 0
    await subscriptions.unsubscribe(subscription)
    count = 0
    discard await client.call("evm_mine", newJArray())
    await sleepAsync(100.millis)
    check count == 0

  test "stops listening to new blocks when provider is closed":
    var count = 0
    proc callback(blck: Block) =
      inc count
    discard await subscriptions.subscribeBlocks(callback)
    discard await client.call("evm_mine", newJArray())
    check eventually count > 0
    await subscriptions.close()
    count = 0
    discard await client.call("evm_mine", newJArray())
    await sleepAsync(100.millis)
    check count == 0

suite "Web socket subscriptions":

  var subscriptions: JsonRpcSubscriptions
  var client: RpcWebSocketClient

  setup:
    client = newRpcWebSocketClient()
    await client.connect("ws://localhost:8545")
    subscriptions = JsonRpcSubscriptions.new(client)
    subscriptions.start()

  teardown:
    await subscriptions.close()
    await client.close()

  subscriptionTests(subscriptions, client)

suite "HTTP polling subscriptions":

  var subscriptions: JsonRpcSubscriptions
  var client: RpcHttpClient

  setup:
    client = newRpcHttpClient()
    await client.connect("http://localhost:8545")
    subscriptions = JsonRpcSubscriptions.new(client,
                                             pollingInterval = 100.millis)
    subscriptions.start()

  teardown:
    await subscriptions.close()
    await client.close()

  subscriptionTests(subscriptions, client)

suite "HTTP polling subscriptions - filter not found":

  var subscriptions: JsonRpcSubscriptions
  var client: RpcHttpClient
  var mockServer: MockRpcHttpServer

  setup:
    echo "Creating MockRpcHttpServer instance"
    mockServer = MockRpcHttpServer.new()
    echo "Starting MockRpcHttpServer..."
    mockServer.start()
    echo "Started MockRpcHttpServer"

    echo "Creating new RpcHttpClient instance..."
    client = newRpcHttpClient()
    echo "Connecting RpcHttpClient to MockRpcHttpServer..."
    await client.connect("http://" & $mockServer.localAddress()[0])
    echo "Connected RpcHttpClient to MockRpcHttpServer"

    echo "Creating new JsonRpcSubscriptions instance..."
    subscriptions = JsonRpcSubscriptions.new(client,
                                             pollingInterval = 100.millis)
    echo "Starting JsonRpcSubscriptions..."
    subscriptions.start()
    echo "Started JsonRpcSubscriptions"

  teardown:
    echo "Closing subscriptions..."
    await subscriptions.close()
    echo "Closing client..."
    await client.close()
    echo "Stopping mock server..."
    await mockServer.stop()
    echo "Stopped mock server"

  test "filter not found error recreates filter":
    echo "1"
    let filter = EventFilter(address: Address.example, topics: @[array[32, byte].example])
    echo "2"
    let emptyHandler = proc(log: Log) = discard
    echo "3"

    check mockServer.newFilterCounter == 0
    echo "4"
    let jsonId = await subscriptions.subscribeLogs(filter, emptyHandler)
    echo "5"
    let id = string.fromJson(jsonId).tryGet
    echo "6"
    check mockServer.newFilterCounter == 1
    echo "7"

    await sleepAsync(200.millis)
    echo "8"
    mockServer.invalidateFilter(id)
    echo "9"
    await sleepAsync(200.millis)
    echo "10"
    check mockServer.newFilterCounter == 2
    echo "11"

  test "recreated filter can be still unsubscribed using the original id":
    let filter = EventFilter(address: Address.example, topics: @[array[32, byte].example])
    let emptyHandler = proc(log: Log) = discard

    check mockServer.newFilterCounter == 0
    let jsonId = await subscriptions.subscribeLogs(filter, emptyHandler)
    let id = string.fromJson(jsonId).tryGet
    check mockServer.newFilterCounter == 1

    await sleepAsync(200.millis)
    mockServer.invalidateFilter(id)
    check eventually mockServer.newFilterCounter == 2
    check mockServer.filters[id] == false
    check mockServer.filters.len() == 2
    await subscriptions.unsubscribe(jsonId)
    check mockServer.filters.len() == 1

    # invalidateFilter sets the filter's value to false which will return the "filter not found"
    # unsubscribing will actually delete the key from filters table
    # hence after unsubscribing the only key left in the table should be the original id
    for key in mockServer.filters.keys():
      check key == id