Fix the issue where the 'Shutdown' method fails to properly exit. #255

uppercaveman · 2025-05-08T02:20:20Z

Summary by CodeRabbit

Refactor
- Improved server startup by optimizing resource locking to enhance performance without changing functionality.

coderabbitai · 2025-05-08T02:20:27Z

"""

Walkthrough

The Start method in the SSEServer struct was modified to change the mutex locking strategy. The lock is now released immediately after copying the srv field, avoiding holding the lock during the blocking ListenAndServe() call.

Changes

File(s)	Change Summary
server/sse.go	Modified `Start` method to unlock mutex immediately after copying `srv` field, preventing lock contention during `ListenAndServe()`.

Possibly related PRs

fix(SSE): only initialize http.Server when not set #229: Modifies the Start method of SSEServer focusing on conditional initialization and address conflict checks for the embedded http.Server, related to changes in Start method locking strategy.
"""

Tip

⚡️ Faster reviews with caching

CodeRabbit now supports caching for code and dependencies, helping speed up reviews. This means quicker feedback, reduced wait times, and a smoother review experience overall. Cached data is encrypted and stored securely. This feature will be automatically enabled for all accounts on May 16th. To opt out, configure Review - Disable Cache at either the organization or repository level. If you prefer to disable all data retention across your organization, simply turn off the Data Retention setting under your Organization Settings.

Enjoy the performance boost—your workflow just got faster.

📜 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 d32050f and dd36a00.

📒 Files selected for processing (1)

server/sse.go (1 hunks)

🚧 Files skipped from review as they are similar to previous changes (1)

server/sse.go

✨ 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

🪧 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.

Support

Need help? Create a ticket on our support page for assistance with any issues or questions.

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 generate sequence diagram to generate a sequence diagram of the changes in 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.

JAORMX · 2025-05-08T10:34:56Z

server/sse.go

-	s.mu.RUnlock()
-
-	if srv != nil {
+	if s.srv != nil {


Can you explain in the commit message why the read lock was causing the shutdown to not work properly? It is not entirely clear to me.

Ya, same. Unless the issue was that we couldn't get a read lock? But I'm not 100% sure why that would be the case...

FWIW, I think #263 explains why it deadlocks fairly well. Basically, upon Start being called we do the following:

s.mu.Lock() defer s.mu.Unlock()

So here in Shutdown() the s.mu.RUnlock() deadlocks (because the defer won't run until Start exits).

This test demonstrates the deadlock described in mark3labs#254 and mark3labs#263 by running `SSEServer.Start` then `SSEServer.Shutdown`. If it deadlocks, the test fails quickly and reliably, rather than hanging indefinitely. References: - mark3labs#254 - mark3labs#255 - mark3labs#263

robert-jackson-glean · 2025-05-09T18:54:52Z

FWIW, I created a test in #264 that fails without hte fixes here and passes with them (confirming the fix here).

JAORMX · 2025-05-09T19:00:36Z

@robert-jackson-glean sounds good! Still, a PR description and/or a commit message that's relevant would be ideal for maintenance in the future.

robert-jackson-glean · 2025-05-09T19:36:27Z

Still, a PR description and/or a commit message that's relevant would be ideal for maintenance in the future.

100% agree!

This test demonstrates the deadlock described in mark3labs#254 and mark3labs#263 by running `SSEServer.Start` then `SSEServer.Shutdown`. If it deadlocks, the test fails quickly and reliably, rather than hanging indefinitely. References: - mark3labs#254 - mark3labs#255 - mark3labs#263

) This test demonstrates the deadlock described in #254 and #263 by running `SSEServer.Start` then `SSEServer.Shutdown`. If it deadlocks, the test fails quickly and reliably, rather than hanging indefinitely. References: - #254 - #255 - #263

Fix the issue where the 'Shutdown' method fails to properly exit.

5daa583

JAORMX reviewed May 8, 2025

View reviewed changes

CHENBING1 and others added 2 commits May 9, 2025 11:01

Fix the issue where the 'Shutdown' method fails to properly exit.

d32050f

Merge branch 'mark3labs:main' into main

dd36a00

robert-jackson-glean mentioned this pull request May 9, 2025

The SSEServer.Shutdown() function deadlocks, preventing the service from shutting down. #263

Closed

robert-jackson-glean mentioned this pull request May 9, 2025

test(server): reliably detect Start/Shutdown deadlock in SSEServer #264

Merged

ezynda3 merged commit 6429019 into mark3labs:main May 10, 2025
3 checks passed

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Fix the issue where the 'Shutdown' method fails to properly exit. #255

Fix the issue where the 'Shutdown' method fails to properly exit. #255

uppercaveman commented May 8, 2025 •

edited by coderabbitai bot

Loading

coderabbitai bot commented May 8, 2025 •

edited

Loading

Chat

Support

CodeRabbit Commands (Invoked using PR comments)

Other keywords and placeholders

CodeRabbit Configuration File (`.coderabbit.yaml`)

Documentation and Community

JAORMX May 8, 2025

robert-jackson-glean May 8, 2025

robert-jackson-glean May 9, 2025

robert-jackson-glean commented May 9, 2025 •

edited

Loading

JAORMX commented May 9, 2025

robert-jackson-glean commented May 9, 2025

Fix the issue where the 'Shutdown' method fails to properly exit. #255

Fix the issue where the 'Shutdown' method fails to properly exit. #255

Conversation

uppercaveman commented May 8, 2025 • edited by coderabbitai bot Loading

Summary by CodeRabbit

coderabbitai bot commented May 8, 2025 • edited Loading

Walkthrough

Changes

Possibly related PRs

Chat

Support

CodeRabbit Commands (Invoked using PR comments)

Other keywords and placeholders

CodeRabbit Configuration File (.coderabbit.yaml)

Documentation and Community

JAORMX May 8, 2025

Choose a reason for hiding this comment

robert-jackson-glean May 8, 2025

Choose a reason for hiding this comment

robert-jackson-glean May 9, 2025

Choose a reason for hiding this comment

robert-jackson-glean commented May 9, 2025 • edited Loading

JAORMX commented May 9, 2025

robert-jackson-glean commented May 9, 2025

uppercaveman commented May 8, 2025 •

edited by coderabbitai bot

Loading

coderabbitai bot commented May 8, 2025 •

edited

Loading

CodeRabbit Configuration File (`.coderabbit.yaml`)

robert-jackson-glean commented May 9, 2025 •

edited

Loading