fix: machine logs timestamp parsing and streaming for systemd <v255

internal/journal/journal.go

@@ -47,7 +47,7 @@ func logs(ctx context.Context, unit string, opts api.ServiceLogsOptions) (io.Rea
 	}
 
 	args = append(args, "-o")
-	args = append(args, "short-iso-precise")
+	args = append(args, "short-unix")
 
 	if opts.Since != "" {
 		args = append(args, "-S")

internal/journal/logs.go

@@ -5,6 +5,7 @@ import (
 	"context"
 	"fmt"
 	"slices"
+	"strconv"
 	"time"
 
 	"github.com/psviderski/uncloud/pkg/api"
@@ -33,17 +34,12 @@ func Logs(ctx context.Context, unit string, opts api.ServiceLogsOptions) (<-chan
 }
 
 func entry(data []byte) api.LogEntry {
-	// 2025-10-12T11:03:27+02:00 systemd[1]:
+	// 1758193407.686964 systemd[1]: ...
 	timestamp := time.Time{}
 	message := data
-	if len(data) > 30 && data[4] == '-' && data[7] == '-' && data[10] == 'T' {
+	if timestampPart, messagePart, found := bytes.Cut(data, []byte(" ")); found {
-		timestampPart, messagePart, found := bytes.Cut(data, []byte(" "))
+		if t, ok := parseUnixTimestamp(timestampPart); ok {
-		var err error
+			timestamp = t
-		if found {
-			timestamp, err = time.Parse(time.RFC3339Nano, string(timestampPart))
-			if err != nil {
-				timestamp = time.Time{}
-			}
 			message = messagePart
 		}
 	}
@@ -54,3 +50,20 @@ func entry(data []byte) api.LogEntry {
 		Stream:    api.LogStreamStdout,
 	}
 }
+
+// parseUnixTimestamp parses a journalctl short-unix timestamp "SSSSSSSSSS.UUUUUU" with microsecond precision.
+func parseUnixTimestamp(b []byte) (time.Time, bool) {
+	secPart, usecPart, found := bytes.Cut(b, []byte("."))
+	if !found {
+		return time.Time{}, false
+	}
+	sec, err := strconv.ParseInt(string(secPart), 10, 64)
+	if err != nil {
+		return time.Time{}, false
+	}
+	usec, err := strconv.ParseInt(string(usecPart), 10, 64)
+	if err != nil {
+		return time.Time{}, false
+	}
+	return time.Unix(sec, usec*1000), true
+}

internal/journal/logs_test.go

@@ -11,6 +11,109 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
+func TestParseUnixTimestamp(t *testing.T) {
+	tests := []struct {
+		name  string
+		input string
+		want  time.Time
+		ok    bool
+	}{
+		{
+			name:  "valid with microseconds",
+			input: "1769188773.687500",
+			want:  time.Unix(1769188773, 687500000),
+			ok:    true,
+		},
+		{
+			name:  "zero microseconds",
+			input: "1769188773.000000",
+			want:  time.Unix(1769188773, 0),
+			ok:    true,
+		},
+		{
+			name:  "epoch",
+			input: "0.000000",
+			want:  time.Unix(0, 0),
+			ok:    true,
+		},
+		{
+			name:  "no fractional part",
+			input: "1769188773",
+			want:  time.Time{},
+			ok:    false,
+		},
+		{
+			name:  "non-numeric seconds",
+			input: "abc.000000",
+			want:  time.Time{},
+			ok:    false,
+		},
+		{
+			name:  "non-numeric microseconds",
+			input: "1769188773.abc",
+			want:  time.Time{},
+			ok:    false,
+		},
+		{
+			name:  "empty",
+			input: "",
+			want:  time.Time{},
+			ok:    false,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, ok := parseUnixTimestamp([]byte(tt.input))
+			assert.Equal(t, tt.ok, ok)
+			assert.True(t, tt.want.Equal(got), "want %v, got %v", tt.want, got)
+		})
+	}
+}
+
+func TestEntry(t *testing.T) {
+	tests := []struct {
+		name      string
+		input     string
+		timestamp time.Time
+		message   string
+	}{
+		{
+			name:      "valid entry",
+			input:     "1769188773.687500 uncloudd[332455]: INFO  Starting daemon.",
+			timestamp: time.Unix(1769188773, 687500000),
+			message:   "uncloudd[332455]: INFO  Starting daemon.\n",
+		},
+		{
+			name:      "unparseable timestamp keeps full line as message",
+			input:     "-- Boot 1234567890 --",
+			timestamp: time.Time{},
+			message:   "-- Boot 1234567890 --\n",
+		},
+		{
+			name:      "line without space keeps full line as message",
+			input:     "nospacehere",
+			timestamp: time.Time{},
+			message:   "nospacehere\n",
+		},
+		{
+			name:      "empty line",
+			input:     "",
+			timestamp: time.Time{},
+			message:   "\n",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := entry([]byte(tt.input))
+			assert.True(t, tt.timestamp.Equal(got.Timestamp), "timestamp: want %v, got %v", tt.timestamp, got.Timestamp)
+			assert.Equal(t, tt.message, string(got.Message))
+			assert.Equal(t, api.LogStreamStdout, got.Stream)
+		})
+	}
+}
+
 func TestLogs(t *testing.T) {
 	commandContext = func(ctx context.Context, _ string, _ ...string) *exec.Cmd {
 		return exec.CommandContext(ctx, "/usr/bin/tail", "testdata/logs")

internal/journal/testdata/logs

@@ -1,6 +1,6 @@
-2026-01-23T17:19:33.686964+01:00 fedora kernel: apple-dcp 271c00000.dcp: DCP index:1 dptx target phy: 5 dptx die: 0
+1769188773.686964 fedora kernel: apple-dcp 271c00000.dcp: DCP index:1 dptx target phy: 5 dptx die: 0
-2026-01-23T17:19:33.687155+01:00 fedora kernel: platform 271c00000.dcp:piodma: Adding to iommu group 9
+1769188773.687155 fedora kernel: platform 271c00000.dcp:piodma: Adding to iommu group 9
-2026-01-23T17:19:33.687343+01:00 fedora kernel: apple-dcp 271c00000.dcp: RTKit: Initializing (protocol version 12)
+1769188773.687343 fedora kernel: apple-dcp 271c00000.dcp: RTKit: Initializing (protocol version 12)
-2026-01-23T17:19:33.687500+01:00 fedora kernel: apple-dcp 271c00000.dcp: shmem_setup: iova: 880255000 -> pa: be4f29000 -> iomem: ffff800082>
+1769188773.687500 fedora kernel: apple-dcp 271c00000.dcp: shmem_setup: iova: 880255000 -> pa: be4f29000 -> iomem: ffff800082>
-2026-01-23T17:19:33.687657+01:00 fedora kernel: apple-dcp 271c00000.dcp: shmem_setup: iova: ffffec000, buffer: ffff8000817cc000
+1769188773.687657 fedora kernel: apple-dcp 271c00000.dcp: shmem_setup: iova: ffffec000, buffer: ffff8000817cc000
-2026-01-23T17:19:33.687826+01:00 fedora kernel: apple-dcp 271c00000.dcp: shmem_setup: iova: ffffe8000, buffer: ffff8000817d4000
+1769188773.687826 fedora kernel: apple-dcp 271c00000.dcp: shmem_setup: iova: ffffe8000, buffer: ffff8000817d4000