Completely random workflow that will hopefully find us a bug! #6594
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| import org.jetbrains.annotations.VisibleForTesting; | ||
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| public final class RandomWorkflows { | ||
| private static final SecureRandom RANDOM = DefaultNativeSamplingSecureRandomFactory.INSTANCE.create(); |
| generateReadActions(), generateWriteActions(), generateDeleteActions()) | ||
| .flatMap(Collection::stream) | ||
| .collect(Collectors.toList()); | ||
| Collections.shuffle(actions); |
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We need to pass in the random here, otherwise this uses the static one in Collections which isn't guaranteed to be our native one.
| } | ||
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| private List<ReadTransactionAction> generateReadActions() { | ||
| return IntStream.range(0, random.nextInt(workflowConfiguration.maxReads())) |
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careful with this: both nextInt and range are exclusive on the end, which means we actually will generate up to maxReads - 1 actions. We should add 1 inside the nextInt call I think - it's ugly, but we do need to distinguish maxReads + 1 possible outcomes (I'm assuming we do want zero as a possibility).
| private List<ReadTransactionAction> generateReadActions() { | ||
| return IntStream.range(0, random.nextInt(workflowConfiguration.maxReads())) | ||
| .boxed() | ||
| .map(index -> ImmutableReadTransactionAction.of( |
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nit: index is unused, so let's name it accordingly
| } | ||
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| private List<WriteTransactionAction> generateWriteActions() { | ||
| return IntStream.range(0, random.nextInt(workflowConfiguration.maxWrites())) |
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as above: be careful with the double exclusion
| this.workflow = RandomWorkflows.create( | ||
| memoryStore, | ||
| CONFIGURATION, | ||
| MoreExecutors.listeningDecorator(PTExecutors.newFixedThreadPool(1)), |
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non actionable: I think we normally use PTExecutors.newSingleThreadExecutor() when we want 1 specifically, though this is fine
| } | ||
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| private List<ReadTransactionAction> generateReadActions() { | ||
| return IntStream.rangeClosed(0, random.nextInt(workflowConfiguration.maxReads())) |
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I did think about rangeClosed, though note that this means we will have at least one of each operation type. If that's the intention that's fine, but wanted to make sure!
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yeah we definitely do not want that
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👍 thanks! |
General
Before this PR:
After this PR:
==COMMIT_MSG==
Adds a workflow which is completely randomly generated.
==COMMIT_MSG==
Priority:
Concerns / possible downsides (what feedback would you like?):
Is documentation needed?:
Compatibility
Does this PR create any API breaks (e.g. at the Java or HTTP layers) - if so, do we have compatibility?:
Does this PR change the persisted format of any data - if so, do we have forward and backward compatibility?:
The code in this PR may be part of a blue-green deploy. Can upgrades from previous versions safely coexist? (Consider restarts of blue or green nodes.):
Does this PR rely on statements being true about other products at a deployment - if so, do we have correct product dependencies on these products (or other ways of verifying that these statements are true)?:
Does this PR need a schema migration?
Testing and Correctness
What, if any, assumptions are made about the current state of the world? If they change over time, how will we find out?:
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If this PR contains complex concurrent or asynchronous code, is it correct? The onus is on the PR writer to demonstrate this.:
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Execution
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Scale
Would this PR be expected to pose a risk at scale? Think of the shopping product at our largest stack.:
Would this PR be expected to perform a large number of database calls, and/or expensive database calls (e.g., row range scans, concurrent CAS)?:
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Development Process
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Please tag any other people who should be aware of this PR:
@jeremyk-91
@sverma30
@raiju