Пример
pool 1.5.2: Run at most N async operations at once in Dart with package:pool, keep the results lined up with the inputs, and know what the timeout actually guards
Проверенный пример — pub pool 1.5.2: Run at most N async operations at once in Dart with package:pool, keep the results lined up with the inputs, and know…
sha256:16a15d010dc0f1c9e1ee0824cafd5bd1ed1eb32530f108bc856e8cc348fa9179
Эта сеть предлагает одно: образец, который собирается. Она запустила его в песочнице и сохранила подписанную квитанцию. Она ничего не оценивает и ничего не гарантирует — собирается ли тот же код у вас, она не измеряла.
Сколько различных ключей подписи подали пройденную квитанцию контракта. Один — только автор; больше одного — значит, кто-то ещё тоже собрал. Ключ создаётся сам и не имеет зарегистрированной личности, поэтому считаются ключи, а не люди.
MIT-0
Свидетельства выполнения
Заявленное окружение и подписанные запуски разделены, чтобы вы точно видели, что этот образец запускал и где.
- Основа свидетельства
- Подписанный контракт пройден
- Квитанции проверки
- 1
- Ключи подписи, собравшие его
- 1
Заявленная среда
dart 3 linux x64 dart 3 dart pub
Среды запусков проверки
| Окружение | Контракт | Этапы | Запуск |
|---|---|---|---|
| dart 3 · linux alpine/x64 · docker ed25519:a2ec939a4c60e243 | PASS | compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS CONTAINER_RUN · pub@1 |
2026-08-14 |
Кейс
HOW- Цель
- Run at most N async operations at once in Dart with package:pool, keep the results lined up with the inputs, and know what the timeout actually guards
- Пакеты
- Символы
-
- Pool
- Pool.withResource
- Pool.request
- Pool.forEach
- Pool.close
- Pool.done
- Pool.isClosed
- PoolResource
- PoolResource.release
- PoolResource.allowRelease
- TimeoutException
- Окружение
- dart 3
- Создан
- 2026-08-14T20:09:50Z
Контракт
- assert a Pool of two runs at most two bodies at once, and that a withResource body that throws still releases its slot, so the high-water mark afterwards is two and not one
- assert pool.forEach emits results in completion order rather than input order, so its list is a permutation of the inputs, while Future.wait over withResource keeps every result in position
- assert forEach holds every resource in the pool for the whole run, so an unrelated request on the same pool is blocked outright rather than throttled alongside it
- assert the default onError adds the error to the stream and carries on, and that returning false only drops the error, with all six elements processed either way
- assert toList on a forEach stream completes with the first error, discards the values already emitted and cancels the iteration, so the remaining elements are never attempted
- assert an error thrown while iterating the elements bypasses onError entirely and lands on the stream even when onError returns false
- assert the timeout is a pool-wide inactivity alarm that any request or release resets, so a starved caller waits nearly three times it, that it then fails every pending request at once with a TimeoutException carrying the configured duration, and that it never fires again for the life of the pool
- assert request() throws StateError synchronously on a closed pool while withResource puts the identical error into its returned future instead, and that close() is memoized to one future
- assert done completes only once the resources handed out before close are released
- assert allowRelease spends the resource token so a following release() throws StateError, that its callback runs only when the slot is wanted, and that a callback which throws completes the next caller's request() with that error and leaves the pool one usable resource short forever
- assert queued requests are answered in request order even when it is a later allowRelease callback that frees the slot
- assert Pool(0) and a negative limit throw ArgumentError from the constructor, and that queued waiters are served first in, first out
Файлы
- csx.json
- lib/throttle.dart
- pubspec.lock
- pubspec.yaml
- test/contract_test.dart