104 lines
2.9 KiB
Nim

import pkg/chronicles
import pkg/chronos
import pkg/questionable
import pkg/questionable/results
import ./dht
import ./list
import ./nodeentry
import ./config
import std/sequtils
logScope:
topics = "crawler"
type Crawler* = ref object
dht: Dht
config: CrawlerConfig
todoNodes: List
okNodes: List
nokNodes: List
# This is not going to stay this way.
proc isNew(c: Crawler, node: Node): bool =
not c.todoNodes.contains(node.id) and not c.okNodes.contains(node.id) and
not c.nokNodes.contains(node.id)
proc handleNodeNotOk(c: Crawler, target: NodeEntry) {.async.} =
if err =? (await c.nokNodes.add(target)).errorOption:
error "Failed to add not-OK-node to list", err = err.msg
proc handleNodeOk(c: Crawler, target: NodeEntry) {.async.} =
if err =? (await c.okNodes.add(target)).errorOption:
error "Failed to add OK-node to list", err = err.msg
proc addNewTodoNode(c: Crawler, nodeId: NodeId): Future[?!void] {.async.} =
let entry = NodeEntry(id: nodeId, lastVisit: 0)
return await c.todoNodes.add(entry)
proc addNewTodoNodes(c: Crawler, newNodes: seq[Node]) {.async.} =
for node in newNodes:
if err =? (await c.addNewTodoNode(node.id)).errorOption:
error "Failed to add todo-node to list", err = err.msg
proc step(c: Crawler) {.async.} =
logScope:
todo = $c.todoNodes.len
ok = $c.okNodes.len
nok = $c.nokNodes.len
without var target =? (await c.todoNodes.pop()), err:
error "Failed to get todo node", err = err.msg
target.lastVisit = Moment.now().epochSeconds.uint64
without receivedNodes =? (await c.dht.getNeighbors(target.id)), err:
await c.handleNodeNotOk(target)
return
let newNodes = receivedNodes.filterIt(isNew(c, it))
if newNodes.len > 0:
trace "Discovered new nodes", newNodes = newNodes.len
await c.handleNodeOk(target)
await c.addNewTodoNodes(newNodes)
# Don't log the status every loop:
if (c.todoNodes.len mod 10) == 0:
trace "Status"
proc worker(c: Crawler) {.async.} =
try:
while true:
await c.step()
await sleepAsync(c.config.stepDelayMs.millis)
except Exception as exc:
error "Exception in crawler worker", msg = exc.msg
quit QuitFailure
proc start*(c: Crawler): Future[?!void] {.async.} =
if c.todoNodes.len < 1:
let nodeIds = c.dht.getRoutingTableNodeIds()
info "Loading routing-table nodes to todo-list...", nodes = nodeIds.len
for id in nodeIds:
if err =? (await c.addNewTodoNode(id)).errorOption:
error "Failed to add routing-table node to todo-list", err = err.msg
return failure(err)
info "Starting crawler...", stepDelayMs = $c.config.stepDelayMs
asyncSpawn c.worker()
return success()
proc new*(
T: type Crawler,
dht: Dht,
todoNodes: List,
okNodes: List,
nokNodes: List,
config: CrawlerConfig,
): Crawler =
Crawler(
dht: dht, todoNodes: todoNodes, okNodes: okNodes, nokNodes: nokNodes, config: config
)