nim-codex/codex/sales/states/preparing.nim

99 lines
3.3 KiB
Nim

import pkg/questionable
import pkg/questionable/results
import pkg/metrics
import ../../logutils
import ../../market
import ../salesagent
import ../statemachine
import ./errorhandling
import ./cancelled
import ./failed
import ./filled
import ./ignored
import ./slotreserving
import ./errored
declareCounter(codex_reservations_availability_mismatch, "codex reservations availability_mismatch")
type
SalePreparing* = ref object of ErrorHandlingState
logScope:
topics = "marketplace sales preparing"
method `$`*(state: SalePreparing): string = "SalePreparing"
method onCancelled*(state: SalePreparing, request: StorageRequest): ?State =
return some State(SaleCancelled())
method onFailed*(state: SalePreparing, request: StorageRequest): ?State =
return some State(SaleFailed())
method onSlotFilled*(state: SalePreparing, requestId: RequestId,
slotIndex: UInt256): ?State =
return some State(SaleFilled())
method run*(state: SalePreparing, machine: Machine): Future[?State] {.async.} =
let agent = SalesAgent(machine)
let data = agent.data
let context = agent.context
let market = context.market
let reservations = context.reservations
await agent.retrieveRequest()
await agent.subscribe()
without request =? data.request:
raiseAssert "no sale request"
let slotId = slotId(data.requestId, data.slotIndex)
let state = await market.slotState(slotId)
if state != SlotState.Free:
return some State(SaleIgnored(reprocessSlot: false, returnBytes: false))
# TODO: Once implemented, check to ensure the host is allowed to fill the slot,
# due to the [sliding window mechanism](https://github.com/codex-storage/codex-research/blob/master/design/marketplace.md#dispersal)
logScope:
slotIndex = data.slotIndex
slotSize = request.ask.slotSize
duration = request.ask.duration
pricePerSlot = request.ask.pricePerSlot
# availability was checked for this slot when it entered the queue, however
# check to the ensure that there is still availability as they may have
# changed since being added (other slots may have been processed in that time)
without availability =? await reservations.findAvailability(
request.ask.slotSize,
request.ask.duration,
request.ask.pricePerSlot,
request.ask.collateral):
debug "No availability found for request, ignoring"
return some State(SaleIgnored(reprocessSlot: true))
info "Availability found for request, creating reservation"
without reservation =? await reservations.createReservation(
availability.id,
request.ask.slotSize,
request.id,
data.slotIndex
), error:
trace "Creation of reservation failed"
# Race condition:
# reservations.findAvailability (line 64) is no guarantee. You can never know for certain that the reservation can be created until after you have it.
# Should createReservation fail because there's no space, we proceed to SaleIgnored.
if error of BytesOutOfBoundsError:
# Lets monitor how often this happen and if it is often we can make it more inteligent to handle it
codex_reservations_availability_mismatch.inc()
return some State(SaleIgnored(reprocessSlot: true))
return some State(SaleErrored(error: error))
trace "Reservation created succesfully"
data.reservation = some reservation
return some State(SaleSlotReserving())