fix: prevent unbounded looping while dequeueing by exiting early when no queues have messages to dequeue

[ericallam]

Summary by CodeRabbit

• Bug Fixes

  • Improved queue processing efficiency by preventing unnecessary looping when no messages can be dequeued, resulting in faster operation under certain conditions.

• Tests

  • Added a new integration test to verify early exit behavior when no messages can be dequeued, ensuring correct and efficient handling of concurrency limits.

[changeset-bot]

⚠️ No Changeset found

Latest commit: 1e305dc

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

Click here to learn what changesets are, and how to add one.

Click here if you're a maintainer who wants to add a changeset to this PR

[coderabbitai]

Walkthrough

The changes modify the RunQueue implementation to make the logger property optional in its options, with a fallback to a default logger if none is provided. The dequeue logic within dequeueMessageFromMasterQueue now tracks whether any messages were successfully dequeued in a full cycle across tenant queues, and exits early if no progress is possible. Additionally, a new integration test verifies this early exit behavior under concurrency-limited conditions, using a mocked logger to assert correct log output and timing.

Changes

File(s)	Change Summary
internal-packages/run-engine/src/run-queue/index.ts	Made logger in RunQueueOptions optional; updated constructor for fallback logger; improved dequeue loop to exit early if no messages are dequeued in a full cycle; added corresponding log message.
internal-packages/run-engine/src/run-queue/tests/dequeueMessageFromMasterQueue.test.ts	Added an integration test for early exit behavior when no messages can be dequeued; used a mock logger for assertions; removed previous logger import/instantiation in test options.

Sequence Diagram(s)

sequenceDiagram
    participant Test as Test Runner
    participant RunQueue as RunQueue
    participant Logger as Logger
    participant Redis as Redis

    Test->>RunQueue: initialize with mock Logger and Redis
    Test->>RunQueue: seed 10 queues (concurrency = 0) with 1 message each
    Test->>RunQueue: call dequeueMessageFromMasterQueue()
    loop For each tenant queue
        RunQueue->>Redis: attempt to dequeue message
        alt Concurrency limit reached
            RunQueue->>Logger: (no dequeue)
        end
    end
    alt No successful dequeues in full cycle
        RunQueue->>Logger: log "No successful dequeues in a full cycle, exiting..."
        RunQueue-->>Test: return (early exit)
    end
    Test->>Logger: assert log message and timing
    Test->>Redis: verify all messages remain enqueued

Loading

Poem

In the warren of queues, a new rule takes the stage,
If no bunnies hop forward, we exit the cage.
With a logger on watch, or a fallback in tow,
We leap out of loops when there’s nowhere to go.
Tests cheer from the burrow, “It’s faster, hooray!”
No more endless circles—just hop on your way!
🐇✨

Tip

⚡💬 Agentic Chat (Pro Plan, General Availability)

• We're introducing multi-step agentic chat in review comments and issue comments, within and outside of PR's. This feature enhances review and issue discussions with the CodeRabbit agentic chat by enabling advanced interactions, including the ability to create pull requests directly from comments and add commits to existing pull requests.

---

📜 Recent review details

Configuration used: CodeRabbit UI
Review profile: CHILL
Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between bbf397e and 1e305dc.

📒 Files selected for processing (2)

• internal-packages/run-engine/src/run-queue/index.ts (5 hunks)
• internal-packages/run-engine/src/run-queue/tests/dequeueMessageFromMasterQueue.test.ts (1 hunks)

⏰ Context from checks skipped due to timeout of 90000ms (7)

• GitHub Check: e2e / 🧪 CLI v3 tests (windows-latest - pnpm)
• GitHub Check: e2e / 🧪 CLI v3 tests (windows-latest - npm)
• GitHub Check: e2e / 🧪 CLI v3 tests (ubuntu-latest - pnpm)
• GitHub Check: units / 🧪 Unit Tests
• GitHub Check: e2e / 🧪 CLI v3 tests (ubuntu-latest - npm)
• GitHub Check: typecheck / typecheck
• GitHub Check: Analyze (javascript-typescript)

🔇 Additional comments (7)

internal-packages/run-engine/src/run-queue/index.ts (6)

52-52: Good improvement to make logger optional.

Making the logger optional in the RunQueueOptions type adds flexibility while maintaining functionality through the fallback implementation.

---

91-91: Good implementation of fallback logger.

Providing a default logger when none is specified ensures consistent logging behavior without requiring API users to always specify a logger.

---

407-408: Well-structured implementation to track successful dequeues.

Adding this flag to track successful dequeues across a full cycle is a clean approach to detect when progress is no longer being made.

---

416-416: Good practice to reset the flag for each new cycle.

Resetting the success tracking flag at the start of each iteration ensures accurate detection of progress in the current cycle.

---

437-437: Appropriate placement of success tracking.

Setting the flag when a message is successfully dequeued is correctly placed right after the successful dequeue operation.

---

449-455: Excellent implementation of early exit mechanism.

This change effectively addresses the PR objective by preventing unbounded looping when no progress can be made. The clear log message will help with monitoring and debugging.

The implementation breaks out of the loop when no successful dequeues occur in a full cycle through all tenant queues, which prevents wasting resources on unproductive iterations.

internal-packages/run-engine/src/run-queue/tests/dequeueMessageFromMasterQueue.test.ts (1)

266-355: Excellent integration test for the early exit feature.

This test thoroughly validates the early exit behavior by:

1. Creating queues with zero concurrency limits to ensure dequeue attempts fail
2. Verifying timing to confirm early exit works as expected
3. Checking log messages to confirm proper logging
4. Verifying queue state to ensure no messages were lost

The mock logger implementation is comprehensive and allows precise verification of the logging behavior.

✨ Finishing Touches

• 📝 Generate Docstrings

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

🪧 Tips

Chat

There are 3 ways to chat with CodeRabbit:

• Review comments: Directly reply to a review comment made by CodeRabbit. Example:
  • I pushed a fix in commit <commit_id>, please review it.
  • Generate unit testing code for this file.
  • Open a follow-up GitHub issue for this discussion.
• Files and specific lines of code (under the "Files changed" tab): Tag @coderabbitai in a new review comment at the desired location with your query. Examples:
  • @coderabbitai generate unit testing code for this file.
  • @coderabbitai modularize this function.
• PR comments: Tag @coderabbitai in a new PR comment to ask questions about the PR branch. For the best results, please provide a very specific query, as very limited context is provided in this mode. Examples:
  • @coderabbitai gather interesting stats about this repository and render them as a table. Additionally, render a pie chart showing the language distribution in the codebase.
  • @coderabbitai read src/utils.ts and generate unit testing code.
  • @coderabbitai read the files in the src/scheduler package and generate a class diagram using mermaid and a README in the markdown format.
  • @coderabbitai help me debug CodeRabbit configuration file.

Note: Be mindful of the bot's finite context window. It's strongly recommended to break down tasks such as reading entire modules into smaller chunks. For a focused discussion, use review comments to chat about specific files and their changes, instead of using the PR comments.

CodeRabbit Commands (Invoked using PR comments)

• @coderabbitai pause to pause the reviews on a PR.
• @coderabbitai resume to resume the paused reviews.
• @coderabbitai review to trigger an incremental review. This is useful when automatic reviews are disabled for the repository.
• @coderabbitai full review to do a full review from scratch and review all the files again.
• @coderabbitai summary to regenerate the summary of the PR.
• @coderabbitai generate docstrings to generate docstrings for this PR.
• @coderabbitai resolve resolve all the CodeRabbit review comments.
• @coderabbitai configuration to show the current CodeRabbit configuration for the repository.
• @coderabbitai help to get help.

Other keywords and placeholders

• Add @coderabbitai ignore anywhere in the PR description to prevent this PR from being reviewed.
• Add @coderabbitai summary to generate the high-level summary at a specific location in the PR description.
• Add @coderabbitai anywhere in the PR title to generate the title automatically.

CodeRabbit Configuration File (.coderabbit.yaml)

• You can programmatically configure CodeRabbit by adding a .coderabbit.yaml file to the root of your repository.
• Please see the configuration documentation for more information.
• If your editor has YAML language server enabled, you can add the path at the top of this file to enable auto-completion and validation: # yaml-language-server: $schema=https://coderabbit.ai/integrations/schema.v2.json

Documentation and Community

• Visit our Documentation for detailed information on how to use CodeRabbit.
• Join our Discord Community to get help, request features, and share feedback.
• Follow us on X/Twitter for updates and announcements.