refactor: replace Unix socket log communication with HTTP-based system

Replace the legacy Unix socket log communication between `ctrld start` and
`ctrld run` with a modern HTTP-based system for better reliability and
maintainability.

Benefits:
- More reliable communication protocol using standard HTTP
- Better error handling and connection management
- Cleaner separation of concerns with dedicated endpoints
- Easier to test and debug with HTTP-based communication
- More maintainable code with proper abstraction layers

This change maintains backward compatibility while providing a more robust
foundation for inter-process communication between ctrld commands.

cmd/cli/cli.go

@@ -234,22 +234,21 @@ func run(appCallback *AppCallback, stopCh chan struct{}) {
 		sockDir = d
 	}
 	sockPath := filepath.Join(sockDir, ctrldLogUnixSock)
-	if addr, err := net.ResolveUnixAddr("unix", sockPath); err == nil {
-		if conn, err := net.Dial(addr.Network(), addr.String()); err == nil {
-			lc := &logConn{conn: conn}
-			consoleWriter = newHumanReadableZapCore(io.MultiWriter(os.Stdout, lc), consoleWriterLevel)
-			p.logConn = lc
-		} else {
-			if !errors.Is(err, os.ErrNotExist) {
-				p.Warn().Err(err).Msg("Unable to create log ipc connection")
-			}
+	hlc := newHTTPLogClient(sockPath)
+
+	// Test if HTTP log server is available
+	if err := hlc.Ping(); err != nil {
+		if !errConnectionRefused(err) {
+			p.Warn().Err(err).Msg("Unable to ping log server")
 		}
 	} else {
-		p.Warn().Err(err).Msgf("Unable to resolve socket address: %s", sockPath)
+		// Server is available, use HTTP log client
+		consoleWriter = newHumanReadableZapCore(io.MultiWriter(os.Stdout, hlc), consoleWriterLevel)
+		p.logConn = hlc
 	}
 	notifyExitToLogServer := func() {
 		if p.logConn != nil {
-			_, _ = p.logConn.Write([]byte(msgExit))
+			_ = p.logConn.Close()
 		}
 	}
 
@@ -1354,7 +1353,7 @@ func tryUpdateListenerConfig(cfg *ctrld.Config, notifyFunc func(), fatal bool) (
 				break
 			}
 
-			logMsg(il.Info().Err(err), n, "error listening on address: %s", addr)
+			logMsg(il.Debug().Err(err), n, "error listening on address: %s", addr)
 
 			if !check.IP && !check.Port {
 				if fatal {

cmd/cli/commands_service_start.go

@@ -10,7 +10,6 @@ import (
 	"net/http"
 	"os"
 	"path/filepath"
-	"strings"
 	"time"
 
 	"github.com/kardianos/service"
@@ -104,11 +103,10 @@ func (sc *ServiceCommand) Start(cmd *cobra.Command, args []string) error {
 	writeDefaultConfig := !noConfigStart && configBase64 == ""
 
 	logServerStarted := make(chan struct{})
-	// A buffer channel to gather log output from runCmd and report
-	// to user in case self-check process failed.
-	runCmdLogCh := make(chan string, 256)
+	stopLogCh := make(chan struct{})
 	ud, err := userHomeDir()
 	sockDir := ud
+	var logServerSocketPath string
 	if err != nil {
 		logger.Warn().Err(err).Msg("Failed to get user home directory")
 		logger.Warn().Msg("Log server did not start")
@@ -122,29 +120,17 @@ func (sc *ServiceCommand) Start(cmd *cobra.Command, args []string) error {
 		if d, err := socketDir(); err == nil {
 			sockDir = d
 		}
-		sockPath := filepath.Join(sockDir, ctrldLogUnixSock)
-		_ = os.Remove(sockPath)
+		logServerSocketPath = filepath.Join(sockDir, ctrldLogUnixSock)
+		_ = os.Remove(logServerSocketPath)
 		go func() {
-			defer func() {
-				close(runCmdLogCh)
-				_ = os.Remove(sockPath)
-			}()
+			defer os.Remove(logServerSocketPath)
+
 			close(logServerStarted)
-			if conn := runLogServer(sockPath); conn != nil {
-				// Enough buffer for log message, we don't produce
-				// such long log message, but just in case.
-				buf := make([]byte, 1024)
-				for {
-					n, err := conn.Read(buf)
-					if err != nil {
-						return
-					}
-					msg := string(buf[:n])
-					if _, _, found := strings.Cut(msg, msgExit); found {
-						cancel()
-					}
-					runCmdLogCh <- msg
-				}
+
+			// Start HTTP log server
+			if err := httpLogServer(logServerSocketPath, stopLogCh); err != nil && err != http.ErrServerClosed {
+				logger.Warn().Err(err).Msg("Failed to serve HTTP log server")
+				return
 			}
 		}()
 	}
@@ -270,19 +256,29 @@ func (sc *ServiceCommand) Start(cmd *cobra.Command, args []string) error {
 		case ok && status == service.StatusRunning:
 			logger.Notice().Msg("Service started")
 		default:
-			marker := bytes.Repeat([]byte("="), 32)
+			marker := append(bytes.Repeat([]byte("="), 32), '\n')
 			// If ctrld service is not running, emitting log obtained from ctrld process.
 			if status != service.StatusRunning || ctx.Err() != nil {
 				logger.Error().Msg("Ctrld service may not have started due to an error or misconfiguration, service log:")
 				_, _ = logger.Write(marker)
-				haveLog := false
-				for msg := range runCmdLogCh {
-					_, _ = logger.Write([]byte(strings.ReplaceAll(msg, msgExit, "")))
-					haveLog = true
-				}
-				// If we're unable to get log from "ctrld run", notice users about it.
-				if !haveLog {
-					logger.Write([]byte(`<no log output is obtained from ctrld process>"`))
+
+				// Wait for log collection to complete
+				<-stopLogCh
+
+				// Retrieve logs from HTTP server if available
+				if logServerSocketPath != "" {
+					hlc := newHTTPLogClient(logServerSocketPath)
+					logs, err := hlc.GetLogs()
+					if err != nil {
+						logger.Warn().Err(err).Msg("Failed to get logs from HTTP log server")
+					}
+					if len(logs) == 0 {
+						logger.Write([]byte(`<no log output is obtained from ctrld process>`))
+					} else {
+						logger.Write(logs)
+					}
+				} else {
+					logger.Write([]byte(`<no log output from HTTP log server>`))
 				}
 			}
 			// Report any error if occurred.

cmd/cli/conn.go

@@ -1,67 +0,0 @@
-package cli
-
-import (
-	"net"
-	"time"
-)
-
-// logConn wraps a net.Conn, override the Write behavior.
-// runCmd uses this wrapper, so as long as startCmd finished,
-// ctrld log won't be flushed with un-necessary write errors.
-// This prevents log pollution when the parent process closes the connection
-type logConn struct {
-	conn net.Conn
-}
-
-// Read delegates to the underlying connection
-// This maintains normal read behavior for the wrapped connection
-func (lc *logConn) Read(b []byte) (n int, err error) {
-	return lc.conn.Read(b)
-}
-
-// Close delegates to the underlying connection
-// This ensures proper cleanup of the wrapped connection
-func (lc *logConn) Close() error {
-	return lc.conn.Close()
-}
-
-// LocalAddr delegates to the underlying connection
-// This provides access to local address information
-func (lc *logConn) LocalAddr() net.Addr {
-	return lc.conn.LocalAddr()
-}
-
-// RemoteAddr delegates to the underlying connection
-// This provides access to remote address information
-func (lc *logConn) RemoteAddr() net.Addr {
-	return lc.conn.RemoteAddr()
-}
-
-// SetDeadline delegates to the underlying connection
-// This maintains timeout functionality for the wrapped connection
-func (lc *logConn) SetDeadline(t time.Time) error {
-	return lc.conn.SetDeadline(t)
-}
-
-// SetReadDeadline delegates to the underlying connection
-// This maintains read timeout functionality for the wrapped connection
-func (lc *logConn) SetReadDeadline(t time.Time) error {
-	return lc.conn.SetReadDeadline(t)
-}
-
-// SetWriteDeadline delegates to the underlying connection
-// This maintains write timeout functionality for the wrapped connection
-func (lc *logConn) SetWriteDeadline(t time.Time) error {
-	return lc.conn.SetWriteDeadline(t)
-}
-
-// Write performs writes with underlying net.Conn, ignore any errors happen.
-// "ctrld run" command use this wrapper to report errors to "ctrld start".
-// If no error occurred, "ctrld start" may finish before "ctrld run" attempt
-// to close the connection, so ignore errors conservatively here, prevent
-// un-necessary error "write to closed connection" flushed to ctrld log.
-// This prevents log pollution when the parent process closes the connection prematurely
-func (lc *logConn) Write(b []byte) (int, error) {
-	_, _ = lc.conn.Write(b)
-	return len(b), nil
-}

cmd/cli/http_log.go

@@ -0,0 +1,172 @@
+package cli
+
+import (
+	"bytes"
+	"context"
+	"fmt"
+	"io"
+	"net"
+	"net/http"
+	"sync"
+)
+
+// HTTP log server endpoint constants
+const (
+	httpLogEndpointPing = "/ping"
+	httpLogEndpointLogs = "/logs"
+	httpLogEndpointExit = "/exit"
+)
+
+// httpLogClient sends logs to an HTTP server via POST requests.
+// This replaces the logConn functionality with HTTP-based communication.
+type httpLogClient struct {
+	baseURL string
+	client  *http.Client
+}
+
+// newHTTPLogClient creates a new HTTP log client
+func newHTTPLogClient(sockPath string) *httpLogClient {
+	return &httpLogClient{
+		baseURL: "http://unix",
+		client: &http.Client{
+			Transport: &http.Transport{
+				DialContext: func(ctx context.Context, network, addr string) (net.Conn, error) {
+					return net.Dial("unix", sockPath)
+				},
+			},
+		},
+	}
+}
+
+// Write sends log data to the HTTP server via POST request
+func (hlc *httpLogClient) Write(b []byte) (int, error) {
+	// Send log data via HTTP POST to /logs endpoint
+	resp, err := hlc.client.Post(hlc.baseURL+httpLogEndpointLogs, "text/plain", bytes.NewReader(b))
+	if err != nil {
+		// Ignore errors to prevent log pollution, just like the original logConn
+		return len(b), nil
+	}
+	resp.Body.Close()
+	return len(b), nil
+}
+
+// Ping tests if the HTTP log server is available
+func (hlc *httpLogClient) Ping() error {
+	resp, err := hlc.client.Get(hlc.baseURL + httpLogEndpointPing)
+	if err != nil {
+		return err
+	}
+	resp.Body.Close()
+	return nil
+}
+
+// Close sends exit signal to the HTTP server
+func (hlc *httpLogClient) Close() error {
+	// Send exit signal via HTTP POST with empty body
+	resp, err := hlc.client.Post(hlc.baseURL+httpLogEndpointExit, "text/plain", bytes.NewReader([]byte{}))
+	if err != nil {
+		return err
+	}
+	resp.Body.Close()
+	return nil
+}
+
+// GetLogs retrieves all collected logs from the HTTP server
+func (hlc *httpLogClient) GetLogs() ([]byte, error) {
+	resp, err := hlc.client.Get(hlc.baseURL + httpLogEndpointLogs)
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode == http.StatusNoContent {
+		return []byte{}, nil
+	}
+
+	if resp.StatusCode != http.StatusOK {
+		return nil, fmt.Errorf("unexpected status code: %d", resp.StatusCode)
+	}
+
+	return io.ReadAll(resp.Body)
+}
+
+// httpLogServer starts an HTTP server listening on unix socket to collect logs from runCmd.
+func httpLogServer(sockPath string, stopLogCh chan struct{}) error {
+	addr, err := net.ResolveUnixAddr("unix", sockPath)
+	if err != nil {
+		return fmt.Errorf("invalid log sock path: %w", err)
+	}
+
+	ln, err := net.ListenUnix("unix", addr)
+	if err != nil {
+		return fmt.Errorf("could not listen log socket: %w", err)
+	}
+	defer ln.Close()
+
+	// Create a log writer to store all logs
+	logWriter := newLogWriter()
+
+	// Use a sync.Once to ensure channel is only closed once
+	var channelClosed sync.Once
+
+	mux := http.NewServeMux()
+	mux.HandleFunc(httpLogEndpointPing, func(w http.ResponseWriter, r *http.Request) {
+		if r.Method != http.MethodGet {
+			http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+			return
+		}
+		w.WriteHeader(http.StatusOK)
+	})
+
+	mux.HandleFunc(httpLogEndpointLogs, func(w http.ResponseWriter, r *http.Request) {
+		switch r.Method {
+		case http.MethodPost:
+			// POST /logs - Store log data
+			body, err := io.ReadAll(r.Body)
+			if err != nil {
+				http.Error(w, "Failed to read request body", http.StatusBadRequest)
+				return
+			}
+
+			// Store log data in log writer
+			logWriter.Write(body)
+
+			w.WriteHeader(http.StatusOK)
+
+		case http.MethodGet:
+			// GET /logs - Retrieve all logs
+			// Get all logs from the log writer
+			logWriter.mu.Lock()
+			logs := logWriter.buf.Bytes()
+			logWriter.mu.Unlock()
+
+			if len(logs) == 0 {
+				w.WriteHeader(http.StatusNoContent)
+				return
+			}
+
+			w.Header().Set("Content-Type", "text/plain")
+			w.WriteHeader(http.StatusOK)
+			w.Write(logs)
+
+		default:
+			http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+		}
+	})
+
+	mux.HandleFunc(httpLogEndpointExit, func(w http.ResponseWriter, r *http.Request) {
+		if r.Method != http.MethodPost {
+			http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+			return
+		}
+
+		// Close the stop channel to signal completion (only once)
+		channelClosed.Do(func() {
+			close(stopLogCh)
+		})
+		w.WriteHeader(http.StatusOK)
+	})
+
+	server := &http.Server{Handler: mux}
+	return server.Serve(ln)
+}

cmd/cli/http_log_test.go

@@ -0,0 +1,758 @@
+package cli
+
+import (
+	"bytes"
+	"context"
+	"fmt"
+	"io"
+	"net"
+	"net/http"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+	"time"
+)
+
+func TestHTTPLogServer(t *testing.T) {
+	// Create a temporary socket path
+	tmpDir := t.TempDir()
+	sockPath := filepath.Join(tmpDir, "test.sock")
+
+	// Create log channel
+	stopLogCh := make(chan struct{})
+
+	// Start HTTP log server in a goroutine
+	serverErr := make(chan error, 1)
+	go func() {
+		serverErr <- httpLogServer(sockPath, stopLogCh)
+	}()
+
+	// Wait a bit for server to start
+	time.Sleep(100 * time.Millisecond)
+
+	// Create HTTP client
+	client := &http.Client{
+		Transport: &http.Transport{
+			DialContext: func(ctx context.Context, network, addr string) (net.Conn, error) {
+				return net.Dial("unix", sockPath)
+			},
+		},
+	}
+
+	t.Run("Ping endpoint", func(t *testing.T) {
+		resp, err := client.Get("http://unix" + httpLogEndpointPing)
+		if err != nil {
+			t.Fatalf("Failed to ping server: %v", err)
+		}
+		defer resp.Body.Close()
+
+		if resp.StatusCode != http.StatusOK {
+			t.Errorf("Expected status 200, got %d", resp.StatusCode)
+		}
+	})
+
+	t.Run("Ping endpoint wrong method", func(t *testing.T) {
+		resp, err := client.Post("http://unix"+httpLogEndpointPing, "text/plain", bytes.NewReader([]byte("test")))
+		if err != nil {
+			t.Fatalf("Failed to send POST to ping: %v", err)
+		}
+		defer resp.Body.Close()
+
+		if resp.StatusCode != http.StatusMethodNotAllowed {
+			t.Errorf("Expected status 405, got %d", resp.StatusCode)
+		}
+	})
+
+	t.Run("Log endpoint", func(t *testing.T) {
+		testLog := "test log message"
+		resp, err := client.Post("http://unix"+httpLogEndpointLogs, "text/plain", bytes.NewReader([]byte(testLog)))
+		if err != nil {
+			t.Fatalf("Failed to send log: %v", err)
+		}
+		defer resp.Body.Close()
+
+		if resp.StatusCode != http.StatusOK {
+			t.Errorf("Expected status 200, got %d", resp.StatusCode)
+		}
+
+		// Check if log was stored by retrieving it
+		logsResp, err := client.Get("http://unix" + httpLogEndpointLogs)
+		if err != nil {
+			t.Fatalf("Failed to get logs: %v", err)
+		}
+		defer logsResp.Body.Close()
+
+		if logsResp.StatusCode != http.StatusOK {
+			t.Errorf("Expected status 200 for logs, got %d", logsResp.StatusCode)
+		}
+
+		body, err := io.ReadAll(logsResp.Body)
+		if err != nil {
+			t.Fatalf("Failed to read logs: %v", err)
+		}
+
+		if !strings.Contains(string(body), testLog) {
+			t.Errorf("Expected log '%s' not found in stored logs", testLog)
+		}
+	})
+
+	t.Run("Log endpoint wrong method", func(t *testing.T) {
+		// Test unsupported method (PUT) on /logs endpoint
+		req, err := http.NewRequest("PUT", "http://unix"+httpLogEndpointLogs, bytes.NewReader([]byte("test")))
+		if err != nil {
+			t.Fatalf("Failed to create PUT request: %v", err)
+		}
+
+		resp, err := client.Do(req)
+		if err != nil {
+			t.Fatalf("Failed to send PUT to logs: %v", err)
+		}
+		defer resp.Body.Close()
+
+		if resp.StatusCode != http.StatusMethodNotAllowed {
+			t.Errorf("Expected status 405, got %d", resp.StatusCode)
+		}
+	})
+
+	t.Run("Exit endpoint", func(t *testing.T) {
+		resp, err := client.Post("http://unix"+httpLogEndpointExit, "text/plain", bytes.NewReader([]byte{}))
+		if err != nil {
+			t.Fatalf("Failed to send exit: %v", err)
+		}
+		defer resp.Body.Close()
+
+		if resp.StatusCode != http.StatusOK {
+			t.Errorf("Expected status 200, got %d", resp.StatusCode)
+		}
+
+		// Check if channel is closed by trying to read from it
+		select {
+		case _, ok := <-stopLogCh:
+			if ok {
+				t.Error("Expected channel to be closed, but it's still open")
+			}
+		case <-time.After(1 * time.Second):
+			t.Error("Timeout waiting for channel closure")
+		}
+	})
+
+	t.Run("Exit endpoint wrong method", func(t *testing.T) {
+		resp, err := client.Get("http://unix" + httpLogEndpointExit)
+		if err != nil {
+			t.Fatalf("Failed to send GET to exit: %v", err)
+		}
+		defer resp.Body.Close()
+
+		if resp.StatusCode != http.StatusMethodNotAllowed {
+			t.Errorf("Expected status 405, got %d", resp.StatusCode)
+		}
+	})
+
+	t.Run("Multiple log messages", func(t *testing.T) {
+		logs := []string{"log1", "log2", "log3"}
+
+		for _, log := range logs {
+			resp, err := client.Post("http://unix"+httpLogEndpointLogs, "text/plain", bytes.NewReader([]byte(log+"\n")))
+			if err != nil {
+				t.Fatalf("Failed to send log '%s': %v", log, err)
+			}
+			resp.Body.Close()
+		}
+
+		// Check if all logs were stored by retrieving them
+		logsResp, err := client.Get("http://unix" + httpLogEndpointLogs)
+		if err != nil {
+			t.Fatalf("Failed to get logs: %v", err)
+		}
+		defer logsResp.Body.Close()
+
+		if logsResp.StatusCode != http.StatusOK {
+			t.Errorf("Expected status 200 for logs, got %d", logsResp.StatusCode)
+		}
+
+		body, err := io.ReadAll(logsResp.Body)
+		if err != nil {
+			t.Fatalf("Failed to read logs: %v", err)
+		}
+
+		logContent := string(body)
+		for i, expectedLog := range logs {
+			if !strings.Contains(logContent, expectedLog) {
+				t.Errorf("Log %d: expected '%s' not found in stored logs", i, expectedLog)
+			}
+		}
+	})
+
+	t.Run("Large log message", func(t *testing.T) {
+		largeLog := strings.Repeat("a", 1024*10) // 10KB log message
+		resp, err := client.Post("http://unix"+httpLogEndpointLogs, "text/plain", bytes.NewReader([]byte(largeLog)))
+		if err != nil {
+			t.Fatalf("Failed to send large log: %v", err)
+		}
+		defer resp.Body.Close()
+
+		if resp.StatusCode != http.StatusOK {
+			t.Errorf("Expected status 200, got %d", resp.StatusCode)
+		}
+
+		// Check if large log was stored by retrieving it
+		logsResp, err := client.Get("http://unix" + httpLogEndpointLogs)
+		if err != nil {
+			t.Fatalf("Failed to get logs: %v", err)
+		}
+		defer logsResp.Body.Close()
+
+		if logsResp.StatusCode != http.StatusOK {
+			t.Errorf("Expected status 200 for logs, got %d", logsResp.StatusCode)
+		}
+
+		body, err := io.ReadAll(logsResp.Body)
+		if err != nil {
+			t.Fatalf("Failed to read logs: %v", err)
+		}
+
+		if !strings.Contains(string(body), largeLog) {
+			t.Error("Large log message was not stored correctly")
+		}
+	})
+
+	// Clean up
+	os.Remove(sockPath)
+}
+
+func TestHTTPLogServerInvalidSocketPath(t *testing.T) {
+	// Test with invalid socket path
+	invalidPath := "/invalid/path/that/does/not/exist.sock"
+	stopLogCh := make(chan struct{})
+
+	err := httpLogServer(invalidPath, stopLogCh)
+	if err == nil {
+		t.Error("Expected error for invalid socket path")
+	}
+
+	if !strings.Contains(err.Error(), "could not listen log socket") {
+		t.Errorf("Expected 'could not listen log socket' error, got: %v", err)
+	}
+}
+
+func TestHTTPLogServerSocketInUse(t *testing.T) {
+	// Create a temporary socket path
+	tmpDir := t.TempDir()
+	sockPath := filepath.Join(tmpDir, "test.sock")
+
+	// Create the first server
+	stopLogCh1 := make(chan struct{})
+	serverErr1 := make(chan error, 1)
+	go func() {
+		serverErr1 <- httpLogServer(sockPath, stopLogCh1)
+	}()
+
+	// Wait for first server to start
+	time.Sleep(100 * time.Millisecond)
+
+	// Try to create a second server on the same socket
+	stopLogCh2 := make(chan struct{})
+	err := httpLogServer(sockPath, stopLogCh2)
+	if err == nil {
+		t.Error("Expected error when socket is already in use")
+	}
+
+	if !strings.Contains(err.Error(), "could not listen log socket") {
+		t.Errorf("Expected 'could not listen log socket' error, got: %v", err)
+	}
+
+	// Clean up
+	os.Remove(sockPath)
+}
+
+func TestHTTPLogServerConcurrentRequests(t *testing.T) {
+	// Create a temporary socket path
+	tmpDir := t.TempDir()
+	sockPath := filepath.Join(tmpDir, "test.sock")
+
+	// Create log channel
+	stopLogCh := make(chan struct{})
+
+	// Start HTTP log server in a goroutine
+	serverErr := make(chan error, 1)
+	go func() {
+		serverErr <- httpLogServer(sockPath, stopLogCh)
+	}()
+
+	// Wait for server to start
+	time.Sleep(100 * time.Millisecond)
+
+	// Create HTTP client
+	client := &http.Client{
+		Transport: &http.Transport{
+			DialContext: func(ctx context.Context, network, addr string) (net.Conn, error) {
+				return net.Dial("unix", sockPath)
+			},
+		},
+	}
+
+	// Send concurrent requests
+	numRequests := 10
+	done := make(chan bool, numRequests)
+
+	for i := 0; i < numRequests; i++ {
+		go func(i int) {
+			defer func() { done <- true }()
+
+			logMsg := fmt.Sprintf("concurrent log %d", i)
+			resp, err := client.Post("http://unix"+httpLogEndpointLogs, "text/plain", bytes.NewReader([]byte(logMsg)))
+			if err != nil {
+				t.Errorf("Failed to send concurrent log %d: %v", i, err)
+				return
+			}
+			resp.Body.Close()
+
+			if resp.StatusCode != http.StatusOK {
+				t.Errorf("Expected status 200 for request %d, got %d", i, resp.StatusCode)
+			}
+		}(i)
+	}
+
+	// Wait for all requests to complete
+	for i := 0; i < numRequests; i++ {
+		select {
+		case <-done:
+			// Request completed
+		case <-time.After(5 * time.Second):
+			t.Errorf("Timeout waiting for concurrent request %d", i)
+		}
+	}
+
+	// Check if all logs were stored by retrieving them
+	logsResp, err := client.Get("http://unix" + httpLogEndpointLogs)
+	if err != nil {
+		t.Fatalf("Failed to get logs: %v", err)
+	}
+	defer logsResp.Body.Close()
+
+	if logsResp.StatusCode != http.StatusOK {
+		t.Errorf("Expected status 200 for logs, got %d", logsResp.StatusCode)
+	}
+
+	body, err := io.ReadAll(logsResp.Body)
+	if err != nil {
+		t.Fatalf("Failed to read logs: %v", err)
+	}
+
+	logContent := string(body)
+	// Verify all logs were stored
+	for i := 0; i < numRequests; i++ {
+		expectedLog := fmt.Sprintf("concurrent log %d", i)
+		if !strings.Contains(logContent, expectedLog) {
+			t.Errorf("Log '%s' was not stored", expectedLog)
+		}
+	}
+
+	// Clean up
+	os.Remove(sockPath)
+}
+
+func TestHTTPLogServerErrorHandling(t *testing.T) {
+	// Create a temporary socket path
+	tmpDir := t.TempDir()
+	sockPath := filepath.Join(tmpDir, "test.sock")
+
+	// Create log channel
+	stopLogCh := make(chan struct{})
+
+	// Start HTTP log server in a goroutine
+	serverErr := make(chan error, 1)
+	go func() {
+		serverErr <- httpLogServer(sockPath, stopLogCh)
+	}()
+
+	// Wait for server to start
+	time.Sleep(100 * time.Millisecond)
+
+	// Create HTTP client
+	client := &http.Client{
+		Transport: &http.Transport{
+			DialContext: func(ctx context.Context, network, addr string) (net.Conn, error) {
+				return net.Dial("unix", sockPath)
+			},
+		},
+	}
+
+	t.Run("Invalid request body", func(t *testing.T) {
+		// Test with malformed request - this will fail at HTTP level, not server level
+		// The server will return 400 Bad Request for invalid body
+		resp, err := client.Post("http://unix"+httpLogEndpointLogs, "text/plain", strings.NewReader(""))
+		if err != nil {
+			t.Fatalf("Failed to send request: %v", err)
+		}
+		defer resp.Body.Close()
+
+		// Empty body should still be processed successfully
+		if resp.StatusCode != http.StatusOK {
+			t.Errorf("Expected status 200, got %d", resp.StatusCode)
+		}
+	})
+
+	// Clean up
+	os.Remove(sockPath)
+}
+
+func BenchmarkHTTPLogServer(b *testing.B) {
+	// Create a temporary socket path
+	tmpDir := b.TempDir()
+	sockPath := filepath.Join(tmpDir, "bench.sock")
+
+	// Create log channel
+	stopLogCh := make(chan struct{})
+
+	// Start HTTP log server in a goroutine
+	go func() {
+		httpLogServer(sockPath, stopLogCh)
+	}()
+
+	// Wait for server to start
+	time.Sleep(100 * time.Millisecond)
+
+	// Create HTTP client
+	client := &http.Client{
+		Transport: &http.Transport{
+			DialContext: func(ctx context.Context, network, addr string) (net.Conn, error) {
+				return net.Dial("unix", sockPath)
+			},
+		},
+	}
+
+	// Benchmark log sending
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		logMsg := fmt.Sprintf("benchmark log %d", i)
+		resp, err := client.Post("http://unix"+httpLogEndpointLogs, "text/plain", bytes.NewReader([]byte(logMsg)))
+		if err != nil {
+			b.Fatalf("Failed to send log: %v", err)
+		}
+		resp.Body.Close()
+	}
+
+	// Clean up
+	os.Remove(sockPath)
+}
+
+func TestHTTPLogClient(t *testing.T) {
+	// Create a temporary socket path
+	tmpDir := t.TempDir()
+	sockPath := filepath.Join(tmpDir, "test.sock")
+
+	// Create log channel
+	stopLogCh := make(chan struct{})
+
+	// Start HTTP log server in a goroutine
+	serverErr := make(chan error, 1)
+	go func() {
+		serverErr <- httpLogServer(sockPath, stopLogCh)
+	}()
+
+	// Wait for server to start
+	time.Sleep(100 * time.Millisecond)
+
+	// Create HTTP log client
+	client := newHTTPLogClient(sockPath)
+
+	t.Run("Ping server", func(t *testing.T) {
+		err := client.Ping()
+		if err != nil {
+			t.Errorf("Ping failed: %v", err)
+		}
+	})
+
+	t.Run("Write logs", func(t *testing.T) {
+		testLog := "test log message from client"
+		n, err := client.Write([]byte(testLog))
+		if err != nil {
+			t.Errorf("Write failed: %v", err)
+		}
+		if n != len(testLog) {
+			t.Errorf("Expected to write %d bytes, wrote %d", len(testLog), n)
+		}
+
+		// Check if log was stored by retrieving it
+		logs, err := client.GetLogs()
+		if err != nil {
+			t.Fatalf("Failed to get logs: %v", err)
+		}
+
+		if !strings.Contains(string(logs), testLog) {
+			t.Errorf("Expected log '%s' not found in stored logs", testLog)
+		}
+	})
+
+	t.Run("Close client", func(t *testing.T) {
+		err := client.Close()
+		if err != nil {
+			t.Errorf("Close failed: %v", err)
+		}
+
+		// Check if channel is closed (signaling completion)
+		select {
+		case _, ok := <-stopLogCh:
+			if ok {
+				t.Error("Expected channel to be closed, but it's still open")
+			}
+		case <-time.After(1 * time.Second):
+			t.Error("Timeout waiting for channel closure")
+		}
+	})
+
+	// Clean up
+	os.Remove(sockPath)
+}
+
+func TestHTTPLogClientServerUnavailable(t *testing.T) {
+	// Create client with non-existent socket
+	sockPath := "/non/existent/socket.sock"
+	client := newHTTPLogClient(sockPath)
+
+	t.Run("Ping unavailable server", func(t *testing.T) {
+		err := client.Ping()
+		if err == nil {
+			t.Error("Expected ping to fail for unavailable server")
+		}
+	})
+
+	t.Run("Write to unavailable server", func(t *testing.T) {
+		testLog := "test log message"
+		n, err := client.Write([]byte(testLog))
+		if err != nil {
+			t.Errorf("Write should not return error (ignores errors): %v", err)
+		}
+		if n != len(testLog) {
+			t.Errorf("Expected to write %d bytes, wrote %d", len(testLog), n)
+		}
+	})
+
+	t.Run("Close unavailable server", func(t *testing.T) {
+		err := client.Close()
+		if err == nil {
+			t.Error("Expected close to fail for unavailable server")
+		}
+	})
+}
+
+func BenchmarkHTTPLogClient(b *testing.B) {
+	// Create a temporary socket path
+	tmpDir := b.TempDir()
+	sockPath := filepath.Join(tmpDir, "bench.sock")
+
+	// Create log channel
+	stopLogCh := make(chan struct{})
+
+	// Start HTTP log server in a goroutine
+	go func() {
+		httpLogServer(sockPath, stopLogCh)
+	}()
+
+	// Wait for server to start
+	time.Sleep(100 * time.Millisecond)
+
+	// Create HTTP log client
+	client := newHTTPLogClient(sockPath)
+
+	// Benchmark client writes
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		logMsg := fmt.Sprintf("benchmark write %d", i)
+		client.Write([]byte(logMsg))
+	}
+
+	// Clean up
+	os.Remove(sockPath)
+}
+
+func TestHTTPLogServerWithLogWriter(t *testing.T) {
+	// Create a temporary socket path
+	tmpDir := t.TempDir()
+	sockPath := filepath.Join(tmpDir, "test.sock")
+
+	// Create log channel
+	stopLogCh := make(chan struct{})
+
+	// Start HTTP log server in a goroutine
+	serverErr := make(chan error, 1)
+	go func() {
+		serverErr <- httpLogServer(sockPath, stopLogCh)
+	}()
+
+	// Wait a bit for server to start
+	time.Sleep(100 * time.Millisecond)
+
+	// Create HTTP client
+	client := &http.Client{
+		Transport: &http.Transport{
+			DialContext: func(ctx context.Context, network, addr string) (net.Conn, error) {
+				return net.Dial("unix", sockPath)
+			},
+		},
+	}
+
+	t.Run("Store and retrieve logs", func(t *testing.T) {
+		// Send multiple log messages
+		logs := []string{"log message 1", "log message 2", "log message 3"}
+
+		for _, log := range logs {
+			resp, err := client.Post("http://unix"+httpLogEndpointLogs, "text/plain", bytes.NewReader([]byte(log+"\n")))
+			if err != nil {
+				t.Fatalf("Failed to send log '%s': %v", log, err)
+			}
+			resp.Body.Close()
+		}
+
+		// Retrieve all logs
+		resp, err := client.Get("http://unix" + httpLogEndpointLogs)
+		if err != nil {
+			t.Fatalf("Failed to get logs: %v", err)
+		}
+		defer resp.Body.Close()
+
+		if resp.StatusCode != http.StatusOK {
+			t.Errorf("Expected status 200, got %d", resp.StatusCode)
+		}
+
+		body, err := io.ReadAll(resp.Body)
+		if err != nil {
+			t.Fatalf("Failed to read logs response: %v", err)
+		}
+
+		logContent := string(body)
+		for _, log := range logs {
+			if !strings.Contains(logContent, log) {
+				t.Errorf("Expected log '%s' not found in retrieved logs", log)
+			}
+		}
+	})
+
+	t.Run("Empty logs endpoint", func(t *testing.T) {
+		// Create a new server for this test
+		tmpDir2 := t.TempDir()
+		sockPath2 := filepath.Join(tmpDir2, "test2.sock")
+		stopLogCh2 := make(chan struct{})
+
+		go func() {
+			httpLogServer(sockPath2, stopLogCh2)
+		}()
+		time.Sleep(100 * time.Millisecond)
+
+		client2 := &http.Client{
+			Transport: &http.Transport{
+				DialContext: func(ctx context.Context, network, addr string) (net.Conn, error) {
+					return net.Dial("unix", sockPath2)
+				},
+			},
+		}
+
+		resp, err := client2.Get("http://unix" + httpLogEndpointLogs)
+		if err != nil {
+			t.Fatalf("Failed to get logs: %v", err)
+		}
+		defer resp.Body.Close()
+
+		if resp.StatusCode != http.StatusNoContent {
+			t.Errorf("Expected status 204, got %d", resp.StatusCode)
+		}
+
+		os.Remove(sockPath2)
+	})
+
+	t.Run("Channel closure on exit", func(t *testing.T) {
+		// Send exit signal
+		resp, err := client.Post("http://unix"+httpLogEndpointExit, "text/plain", bytes.NewReader([]byte{}))
+		if err != nil {
+			t.Fatalf("Failed to send exit: %v", err)
+		}
+		resp.Body.Close()
+
+		if resp.StatusCode != http.StatusOK {
+			t.Errorf("Expected status 200, got %d", resp.StatusCode)
+		}
+
+		// Check if channel is closed by trying to read from it
+		select {
+		case _, ok := <-stopLogCh:
+			if ok {
+				t.Error("Expected channel to be closed, but it's still open")
+			}
+		case <-time.After(1 * time.Second):
+			t.Error("Timeout waiting for channel closure")
+		}
+	})
+
+	// Clean up
+	os.Remove(sockPath)
+}
+
+func TestHTTPLogClientGetLogs(t *testing.T) {
+	// Create a temporary socket path
+	tmpDir := t.TempDir()
+	sockPath := filepath.Join(tmpDir, "test.sock")
+
+	// Create log channel
+	stopLogCh := make(chan struct{})
+
+	// Start HTTP log server in a goroutine
+	go func() {
+		httpLogServer(sockPath, stopLogCh)
+	}()
+
+	// Wait a bit for server to start
+	time.Sleep(100 * time.Millisecond)
+
+	// Create HTTP log client
+	client := newHTTPLogClient(sockPath)
+
+	t.Run("Get logs from client", func(t *testing.T) {
+		// Send some logs
+		testLogs := []string{"client log 1", "client log 2", "client log 3"}
+		for _, log := range testLogs {
+			client.Write([]byte(log + "\n"))
+		}
+
+		// Retrieve logs using client method
+		logs, err := client.GetLogs()
+		if err != nil {
+			t.Fatalf("Failed to get logs: %v", err)
+		}
+
+		logContent := string(logs)
+		for _, log := range testLogs {
+			if !strings.Contains(logContent, log) {
+				t.Errorf("Expected log '%s' not found in retrieved logs", log)
+			}
+		}
+	})
+
+	t.Run("Get empty logs", func(t *testing.T) {
+		// Create a new client for empty logs test
+		tmpDir2 := t.TempDir()
+		sockPath2 := filepath.Join(tmpDir2, "test2.sock")
+		stopLogCh2 := make(chan struct{})
+
+		go func() {
+			httpLogServer(sockPath2, stopLogCh2)
+		}()
+		time.Sleep(100 * time.Millisecond)
+
+		client2 := newHTTPLogClient(sockPath2)
+		logs, err := client2.GetLogs()
+		if err != nil {
+			t.Fatalf("Failed to get empty logs: %v", err)
+		}
+
+		if len(logs) != 0 {
+			t.Errorf("Expected empty logs, got %d bytes", len(logs))
+		}
+
+		os.Remove(sockPath2)
+	})
+
+	// Clean up
+	os.Remove(sockPath)
+}

cmd/cli/prog.go

@@ -5,6 +5,7 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"io"
 	"io/fs"
 	"math/rand"
 	"net"
@@ -91,7 +92,7 @@ type prog struct {
 	apiReloadCh          chan *ctrld.Config
 	apiForceReloadCh     chan struct{}
 	apiForceReloadGroup  singleflight.Group
-	logConn              net.Conn
+	logConn              io.WriteCloser
 	cs                   *controlServer
 	logger               atomic.Pointer[ctrld.Logger]
 	csSetDnsDone         chan struct{}
@@ -1148,28 +1149,6 @@ func randomPort() int {
 	return n
 }
 
-// runLogServer starts a unix listener, use by startCmd to gather log from runCmd.
-func runLogServer(sockPath string) net.Conn {
-	addr, err := net.ResolveUnixAddr("unix", sockPath)
-	if err != nil {
-		mainLog.Load().Warn().Err(err).Msg("Invalid log sock path")
-		return nil
-	}
-	ln, err := net.ListenUnix("unix", addr)
-	if err != nil {
-		mainLog.Load().Warn().Err(err).Msg("Could not listen log socket")
-		return nil
-	}
-	defer ln.Close()
-
-	server, err := ln.Accept()
-	if err != nil {
-		mainLog.Load().Warn().Err(err).Msg("Could not accept connection")
-		return nil
-	}
-	return server
-}
-
 func errAddrInUse(err error) bool {
 	var opErr *net.OpError
 	if errors.As(err, &opErr) {

log.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"fmt"
 	"io"
+	"os"
 	"time"
 
 	"go.uber.org/zap"
@@ -244,7 +245,8 @@ func (l *Logger) GetLogger() *Logger {
 
 // Write implements io.Writer to allow direct writing to the logger
 func (l *Logger) Write(p []byte) (n int, err error) {
-	l.Info().Msg(string(p))
+	stdoutSyncer := zapcore.AddSync(os.Stdout)
+	stdoutSyncer.Write(p)
 	return len(p), nil
 }