fix: prevent libp2p panic by reusing gRPC connections in multi-publish

[swarna1101]

Summary by CodeRabbit

Release Notes

• Chores
  • Updated Go toolchain from version 1.24.1 to 1.25.5
  • Upgraded linting tool from v2.0.1 to v2.8.0
  • Enhanced CI pipeline with additional build step visibility
  • Optimized connection handling for improved performance
  • Cleaned up project configuration files

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[coderabbitai]

📝 Walkthrough

Walkthrough

The PR updates Go toolchain versions across the codebase from 1.24.1 to 1.25.5, bumps CI linting tool version, refactors GRPC connection handling in the multi-publish client to reuse connections across iterations instead of recreating per-iteration, adds log file ignores, and cleans up module dependencies.

Changes

Cohort / File(s)	Summary
Go Toolchain Version Updates grpc_p2p_client/go.mod, grpc_proxy_client/go.mod, keygen/go.mod	Bumped Go version from 1.24.1 to 1.25.5 across three module files. keygen/go.mod additionally adds explicit require for github.com/libp2p/go-libp2p v0.24.0 and tidies up indirect transitive dependencies.
CI Configuration & Logging .github/workflows/ci.yml	Bumped linter version from v2.0.1 to v2.8.0. Added user-facing echo messages after three build/test steps (Build Proxy Client, Build Key Generator, Test Key Generation) to indicate successful execution.
Build Configuration .gitignore	Added new ignore rule to exclude all \*.log files from version control.
GRPC Client Refactoring grpc_p2p_client/cmd/multi-publish/main.go	Refactored connection initialization to establish GRPC client connection and CommandStream once before the loop, then reuse across iterations instead of creating new connections per-iteration. Updated error handling to return errors within loop instead of fatal logs. Added deferred connection close and success log message upon connection. Changed header generation to string constant.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~12 minutes

Possibly related PRs

• fix: refactor grpc_p2p_client to resolve multiple main() conflict #57: Modifies grpc_p2p_client/cmd/multi-publish/main.go with similar connection/stream handling refactoring and shared logic changes.

Suggested reviewers

• hpsing
• paiva

Poem

🐰 With Go 1.25.5 we now hop faster,
Connections reused—no more disasters!
Log files ignored, dependencies tidy,
The rabbit approves—let's merge this nidy! ✨

🚥 Pre-merge checks | ✅ 3

✅ Passed checks (3 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately describes the main change: reusing gRPC connections in multi-publish to prevent libp2p panic, which aligns with the primary architectural improvement in grpc_p2p_client/cmd/multi-publish/main.go.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

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✨ Finishing touches

• 📝 Generate docstrings

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[coderabbitai]

Actionable comments posted: 0

Caution

Some comments are outside the diff and can’t be posted inline due to platform limitations.

⚠️ Outside diff range comments (1)

grpc_p2p_client/cmd/multi-publish/main.go (1)

79-84: Error return value is ignored, silently discarding connection and stream failures.

sendMessages returns an error, but the caller discards it. This means connection failures, stream errors, and context cancellations go unreported—undermining the PR's goal of fixing connection issues.

🔧 Proposed fix to handle the error

 		go func(ip string) {
 			defer wg.Done()
 			datasize := *dataSize
-			sendMessages(ctx, ip, datasize, *output != "", dataCh)
+			if err := sendMessages(ctx, ip, datasize, *output != "", dataCh); err != nil {
+				log.Printf("Error sending messages to %s: %v", ip, err)
+			}
 		}(ip)

🧹 Nitpick comments (3)

grpc_p2p_client/cmd/multi-publish/main.go (3)

106-110: Stream is never closed; consider calling CloseSend() after the loop.

For bidirectional gRPC streams, the client should call stream.CloseSend() when finished sending to properly signal the server. Without this, the server may not know the client is done, potentially causing resource leaks or hangs.

♻️ Proposed fix to close the stream

 	client := protobuf.NewCommandStreamClient(conn)
 	stream, err := client.ListenCommands(ctx)
 	if err != nil {
 		return fmt.Errorf("[%s] ListenCommands failed: %w", ip, err)
 	}
+	defer stream.CloseSend()

 	println(fmt.Sprintf("Connected to node at: %s…", ip))

---

112-112: Use fmt.Printf or log.Printf instead of println.

println is a built-in intended for bootstrapping/debugging, not production code. It writes to stderr and has inconsistent formatting across platforms.

♻️ Proposed fix

-	println(fmt.Sprintf("Connected to node at: %s…", ip))
+	log.Printf("Connected to node at: %s…", ip)

---

71-74: Simplify nested goroutine by removing unnecessary wrapper.

The outer goroutine only spawns an inner goroutine and exits immediately. This adds complexity without benefit.

♻️ Proposed simplification

 	if *output != "" {
 		done = make(chan bool)
-		go func() {
-			header := "sender\tsize\tsha256(msg)"
-			go shared.WriteToFile(ctx, dataCh, done, *output, header)
-		}()
+		header := "sender\tsize\tsha256(msg)"
+		go shared.WriteToFile(ctx, dataCh, done, *output, header)
 	}