nim-codex/codex/sales/reservations.nim

501 lines
15 KiB
Nim

## Nim-Codex
## Copyright (c) 2022 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.
##
## +--------------------------------------+
## | RESERVATION |
## +--------------------------------------+ |--------------------------------------|
## | AVAILABILITY | | ReservationId | id | PK |
## |--------------------------------------| |--------------------------------------|
## | AvailabilityId | id | PK |<-||-------o<-| AvailabilityId | availabilityId | FK |
## |--------------------------------------| |--------------------------------------|
## | UInt256 | size | | | UInt256 | size | |
## |--------------------------------------| |--------------------------------------|
## | UInt256 | duration | | | SlotId | slotId | |
## |--------------------------------------| +--------------------------------------+
## | UInt256 | minPrice | |
## |--------------------------------------|
## | UInt256 | maxCollateral | |
## +--------------------------------------+
import pkg/upraises
push: {.upraises: [].}
import std/typetraits
import pkg/chronos
import pkg/chronicles
import pkg/datastore
import pkg/nimcrypto
import pkg/questionable
import pkg/questionable/results
import pkg/stint
import pkg/stew/byteutils
import ../stores
import ../contracts/requests
import ../utils/json
export requests
export chronicles
logScope:
topics = "sales reservations"
type
AvailabilityId* = distinct array[32, byte]
ReservationId* = distinct array[32, byte]
SomeStorableObject = Availability | Reservation
SomeStorableId = AvailabilityId | ReservationId
Availability* = ref object
id* {.serialize.}: AvailabilityId
size* {.serialize.}: UInt256
duration* {.serialize.}: UInt256
minPrice* {.serialize.}: UInt256
maxCollateral* {.serialize.}: UInt256
Reservation* = ref object
id* {.serialize.}: ReservationId
availabilityId* {.serialize.}: AvailabilityId
size* {.serialize.}: UInt256
requestId* {.serialize.}: RequestId
slotIndex* {.serialize.}: UInt256
Reservations* = ref object
repo: RepoStore
onAvailabilityAdded: ?OnAvailabilityAdded
GetNext* = proc(): Future[?seq[byte]] {.upraises: [], gcsafe, closure.}
OnAvailabilityAdded* = proc(availability: Availability): Future[void] {.upraises: [], gcsafe.}
StorableIter* = ref object
finished*: bool
next*: GetNext
ReservationsError* = object of CodexError
ReserveFailedError* = object of ReservationsError
ReleaseFailedError* = object of ReservationsError
DeleteFailedError* = object of ReservationsError
GetFailedError* = object of ReservationsError
NotExistsError* = object of ReservationsError
SerializationError* = object of ReservationsError
UpdateFailedError* = object of ReservationsError
BytesOutOfBoundsError* = object of ReservationsError
const
SalesKey = (CodexMetaKey / "sales").tryGet # TODO: move to sales module
ReservationsKey = (SalesKey / "reservations").tryGet
proc new*(T: type Reservations,
repo: RepoStore): Reservations =
T(repo: repo)
proc init*(
_: type Availability,
size: UInt256,
duration: UInt256,
minPrice: UInt256,
maxCollateral: UInt256): Availability =
var id: array[32, byte]
doAssert randomBytes(id) == 32
Availability(id: AvailabilityId(id), size: size, duration: duration, minPrice: minPrice, maxCollateral: maxCollateral)
proc init*(
_: type Reservation,
availabilityId: AvailabilityId,
size: UInt256,
requestId: RequestId,
slotIndex: UInt256
): Reservation =
var id: array[32, byte]
doAssert randomBytes(id) == 32
Reservation(id: ReservationId(id), availabilityId: availabilityId, size: size, requestId: requestId, slotIndex: slotIndex)
func toArray(id: SomeStorableId): array[32, byte] =
array[32, byte](id)
proc `==`*(x, y: AvailabilityId): bool {.borrow.}
proc `==`*(x, y: ReservationId): bool {.borrow.}
proc `==`*(x, y: Reservation): bool =
x.id == y.id and
x.availabilityId == y.availabilityId and
x.size == y.size and
x.requestId == y.requestId and
x.slotIndex == y.slotIndex
proc `==`*(x, y: Availability): bool =
x.id == y.id and
x.size == y.size and
x.duration == y.duration and
x.maxCollateral == y.maxCollateral and
x.minPrice == y.minPrice
proc `$`*(id: SomeStorableId): string = id.toArray.toHex
proc toErr[E1: ref CatchableError, E2: ReservationsError](
e1: E1,
_: type E2,
msg: string = e1.msg): ref E2 =
return newException(E2, msg, e1)
proc writeValue*(
writer: var JsonWriter,
value: SomeStorableId) {.upraises:[IOError].} =
## used for chronicles' logs
mixin writeValue
writer.writeValue %value
proc `onAvailabilityAdded=`*(self: Reservations,
onAvailabilityAdded: OnAvailabilityAdded) =
self.onAvailabilityAdded = some onAvailabilityAdded
func key*(id: AvailabilityId): ?!Key =
## sales / reservations / <availabilityId>
(ReservationsKey / $id)
func key*(reservationId: ReservationId, availabilityId: AvailabilityId): ?!Key =
## sales / reservations / <availabilityId> / <reservationId>
(availabilityId.key / $reservationId)
func key*(availability: Availability): ?!Key =
return availability.id.key
func key*(reservation: Reservation): ?!Key =
return key(reservation.id, reservation.availabilityId)
func available*(self: Reservations): uint = self.repo.available
func hasAvailable*(self: Reservations, bytes: uint): bool =
self.repo.available(bytes)
proc exists*(
self: Reservations,
key: Key): Future[bool] {.async.} =
let exists = await self.repo.metaDs.contains(key)
return exists
proc getImpl(
self: Reservations,
key: Key): Future[?!seq[byte]] {.async.} =
if not await self.exists(key):
let err = newException(NotExistsError, "object with key " & $key & " does not exist")
return failure(err)
without serialized =? await self.repo.metaDs.get(key), error:
return failure(error.toErr(GetFailedError))
return success serialized
proc get*(
self: Reservations,
key: Key,
T: type SomeStorableObject): Future[?!T] {.async.} =
without serialized =? await self.getImpl(key), error:
return failure(error)
without obj =? T.fromJson(serialized), error:
return failure(error.toErr(SerializationError))
return success obj
proc update(
self: Reservations,
obj: SomeStorableObject): Future[?!void] {.async.} =
trace "updating " & $(obj.type), id = obj.id, size = obj.size
without key =? obj.key, error:
return failure(error)
if err =? (await self.repo.metaDs.put(
key,
@(obj.toJson.toBytes)
)).errorOption:
return failure(err.toErr(UpdateFailedError))
return success()
proc delete(
self: Reservations,
key: Key): Future[?!void] {.async.} =
trace "deleting object", key
if not await self.exists(key):
return success()
if err =? (await self.repo.metaDs.delete(key)).errorOption:
return failure(err.toErr(DeleteFailedError))
return success()
proc deleteReservation*(
self: Reservations,
reservationId: ReservationId,
availabilityId: AvailabilityId): Future[?!void] {.async.} =
logScope:
reservationId
availabilityId
trace "deleting reservation"
without key =? key(reservationId, availabilityId), error:
return failure(error)
without reservation =? (await self.get(key, Reservation)), error:
if error of NotExistsError:
return success()
else:
return failure(error)
if reservation.size > 0.u256:
trace "returning remaining reservation bytes to availability",
size = reservation.size
without availabilityKey =? availabilityId.key, error:
return failure(error)
without var availability =? await self.get(availabilityKey, Availability), error:
return failure(error)
availability.size += reservation.size
if updateErr =? (await self.update(availability)).errorOption:
return failure(updateErr)
if err =? (await self.repo.metaDs.delete(key)).errorOption:
return failure(err.toErr(DeleteFailedError))
return success()
proc createAvailability*(
self: Reservations,
size: UInt256,
duration: UInt256,
minPrice: UInt256,
maxCollateral: UInt256): Future[?!Availability] {.async.} =
trace "creating availability", size, duration, minPrice, maxCollateral
let availability = Availability.init(
size, duration, minPrice, maxCollateral
)
let bytes = availability.size.truncate(uint)
if reserveErr =? (await self.repo.reserve(bytes)).errorOption:
return failure(reserveErr.toErr(ReserveFailedError))
if updateErr =? (await self.update(availability)).errorOption:
# rollback the reserve
trace "rolling back reserve"
if rollbackErr =? (await self.repo.release(bytes)).errorOption:
rollbackErr.parent = updateErr
return failure(rollbackErr)
return failure(updateErr)
if onAvailabilityAdded =? self.onAvailabilityAdded:
try:
await onAvailabilityAdded(availability)
except CatchableError as e:
# we don't have any insight into types of errors that `onProcessSlot` can
# throw because it is caller-defined
warn "Unknown error during 'onAvailabilityAdded' callback",
availabilityId = availability.id, error = e.msg
return success(availability)
proc createReservation*(
self: Reservations,
availabilityId: AvailabilityId,
slotSize: UInt256,
requestId: RequestId,
slotIndex: UInt256
): Future[?!Reservation] {.async.} =
trace "creating reservation", availabilityId, slotSize, requestId, slotIndex
let reservation = Reservation.init(availabilityId, slotSize, requestId, slotIndex)
without availabilityKey =? availabilityId.key, error:
return failure(error)
without var availability =? await self.get(availabilityKey, Availability), error:
return failure(error)
if availability.size < slotSize:
let error = newException(BytesOutOfBoundsError, "trying to reserve an " &
"amount of bytes that is greater than the total size of the Availability")
return failure(error)
if createResErr =? (await self.update(reservation)).errorOption:
return failure(createResErr)
# reduce availability size by the slot size, which is now accounted for in
# the newly created Reservation
availability.size -= slotSize
# update availability with reduced size
if updateErr =? (await self.update(availability)).errorOption:
trace "rolling back reservation creation"
without key =? reservation.key, keyError:
keyError.parent = updateErr
return failure(keyError)
# rollback the reservation creation
if rollbackErr =? (await self.delete(key)).errorOption:
rollbackErr.parent = updateErr
return failure(rollbackErr)
return failure(updateErr)
return success(reservation)
proc release*(
self: Reservations,
reservationId: ReservationId,
availabilityId: AvailabilityId,
bytes: uint): Future[?!void] {.async.} =
logScope:
topics = "release"
bytes
reservationId
availabilityId
trace "releasing bytes and updating reservation"
without key =? key(reservationId, availabilityId), error:
return failure(error)
without var reservation =? (await self.get(key, Reservation)), error:
return failure(error)
if reservation.size < bytes.u256:
let error = newException(BytesOutOfBoundsError,
"trying to release an amount of bytes that is greater than the total " &
"size of the Reservation")
return failure(error)
if releaseErr =? (await self.repo.release(bytes)).errorOption:
return failure(releaseErr.toErr(ReleaseFailedError))
reservation.size -= bytes.u256
# persist partially used Reservation with updated size
if err =? (await self.update(reservation)).errorOption:
# rollback release if an update error encountered
trace "rolling back release"
if rollbackErr =? (await self.repo.reserve(bytes)).errorOption:
rollbackErr.parent = err
return failure(rollbackErr)
return failure(err)
return success()
iterator items(self: StorableIter): Future[?seq[byte]] =
while not self.finished:
yield self.next()
proc storables(
self: Reservations,
T: type SomeStorableObject
): Future[?!StorableIter] {.async.} =
var iter = StorableIter()
let query = Query.init(ReservationsKey)
when T is Availability:
# should indicate key length of 4, but let the .key logic determine it
without defaultKey =? AvailabilityId.default.key, error:
return failure(error)
elif T is Reservation:
# should indicate key length of 5, but let the .key logic determine it
without defaultKey =? key(ReservationId.default, AvailabilityId.default), error:
return failure(error)
else:
raiseAssert "unknown type"
without results =? await self.repo.metaDs.query(query), error:
return failure(error)
proc next(): Future[?seq[byte]] {.async.} =
await idleAsync()
iter.finished = results.finished
if not results.finished and
res =? (await results.next()) and
res.data.len > 0 and
key =? res.key and
key.namespaces.len == defaultKey.namespaces.len:
return some res.data
return none seq[byte]
iter.next = next
return success iter
proc all*(
self: Reservations,
T: type SomeStorableObject
): Future[?!seq[T]] {.async.} =
var ret: seq[T] = @[]
without storables =? (await self.storables(T)), error:
return failure(error)
for storable in storables.items:
without bytes =? (await storable):
continue
without obj =? T.fromJson(bytes), error:
error "json deserialization error",
json = string.fromBytes(bytes),
error = error.msg
continue
ret.add obj
return success(ret)
proc findAvailability*(
self: Reservations,
size, duration, minPrice, collateral: UInt256
): Future[?Availability] {.async.} =
without storables =? (await self.storables(Availability)), e:
error "failed to get all storables", error = e.msg
return none Availability
for item in storables.items:
if bytes =? (await item) and
availability =? Availability.fromJson(bytes):
if size <= availability.size and
duration <= availability.duration and
collateral <= availability.maxCollateral and
minPrice >= availability.minPrice:
trace "availability matched",
size, availsize = availability.size,
duration, availDuration = availability.duration,
minPrice, availMinPrice = availability.minPrice,
collateral, availMaxCollateral = availability.maxCollateral
return some availability
trace "availiability did not match",
size, availsize = availability.size,
duration, availDuration = availability.duration,
minPrice, availMinPrice = availability.minPrice,
collateral, availMaxCollateral = availability.maxCollateral