fix(logs): resolve time ranges using client local time zone for logs commands

cmd/uc/machine/logs.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"slices"
 	"strings"
+	"time"
 
 	"github.com/psviderski/uncloud/internal/cli"
 	"github.com/psviderski/uncloud/internal/cli/completion"
@@ -64,6 +65,11 @@ If no services are specified, streams logs from the uncloud service.`,
 }
 
 func runLogs(ctx context.Context, uncli *cli.CLI, services []string, opts logs.Options) error {
+	since, until, err := logs.TimeRange(opts.Since, opts.Until, time.Now())
+	if err != nil {
+		return err
+	}
+
 	if len(services) == 0 {
 		services = []string{api.SystemServiceUncloud}
 	}
@@ -88,8 +94,8 @@ func runLogs(ctx context.Context, uncli *cli.CLI, services []string, opts logs.O
 	logsOpts := api.ServiceLogsOptions{
 		Follow:   opts.Follow,
 		Tail:     tail,
-		Since:    opts.Since,
+		Since:    since,
-		Until:    opts.Until,
+		Until:    until,
 		Machines: cli.ExpandCommaSeparatedValues(opts.Machines),
 	}
 

cmd/uc/machine/logs_test.go

@@ -0,0 +1,25 @@
+package machine
+
+import (
+	"context"
+	"testing"
+
+	"github.com/psviderski/uncloud/internal/cli/logs"
+	"github.com/stretchr/testify/require"
+)
+
+func TestRunLogsInvalidTimeFilters(t *testing.T) {
+	t.Parallel()
+
+	// Invalid filters must fail before connecting to the cluster.
+	for _, flag := range []string{"since", "until"} {
+		opts := logs.Options{}
+		if flag == "since" {
+			opts.Since = "invalid"
+		} else {
+			opts.Until = "invalid"
+		}
+		err := runLogs(context.Background(), nil, nil, opts)
+		require.ErrorContains(t, err, "invalid --"+flag+" value")
+	}
+}

cmd/uc/service/logs.go

@@ -5,6 +5,7 @@ import (
 	"errors"
 	"fmt"
 	"strings"
+	"time"
 
 	mapset "github.com/deckarep/golang-set/v2"
 	"github.com/psviderski/uncloud/internal/cli"
@@ -78,6 +79,11 @@ If no services are specified, streams logs from all services defined in the Comp
 }
 
 func RunLogs(ctx context.Context, uncli *cli.CLI, args []string, opts logs.Options) error {
+	since, until, err := logs.TimeRange(opts.Since, opts.Until, time.Now())
+	if err != nil {
+		return err
+	}
+
 	serviceArgs, err := logs.ParseServiceArgs(args)
 	if err != nil {
 		return err
@@ -121,8 +127,8 @@ func RunLogs(ctx context.Context, uncli *cli.CLI, args []string, opts logs.Optio
 	baseOpts := api.ServiceLogsOptions{
 		Follow:   opts.Follow,
 		Tail:     tail,
-		Since:    opts.Since,
+		Since:    since,
-		Until:    opts.Until,
+		Until:    until,
 		Machines: cli.ExpandCommaSeparatedValues(opts.Machines),
 	}
 

cmd/uc/service/logs_test.go

@@ -0,0 +1,25 @@
+package service
+
+import (
+	"context"
+	"testing"
+
+	"github.com/psviderski/uncloud/internal/cli/logs"
+	"github.com/stretchr/testify/require"
+)
+
+func TestRunLogsInvalidTimeFilters(t *testing.T) {
+	t.Parallel()
+
+	// Invalid filters must fail before loading Compose files or connecting to the cluster.
+	for _, flag := range []string{"since", "until"} {
+		opts := logs.Options{}
+		if flag == "since" {
+			opts.Since = "invalid"
+		} else {
+			opts.Until = "invalid"
+		}
+		err := RunLogs(context.Background(), nil, nil, opts)
+		require.ErrorContains(t, err, "invalid --"+flag+" value")
+	}
+}

internal/cli/logs/logs.go

@@ -31,8 +31,8 @@ func Flags(options *Options) *pflag.FlagSet {
 			"Examples:\n"+
 			"  --since 2m30s                      Relative duration (2 minutes 30 seconds ago)\n"+
 			"  --since 1h                         Relative duration (1 hour ago)\n"+
-			"  --since 2025-11-24                 RFC 3339 date only (midnight using local timezone)\n"+
+			"  --since 2025-11-24                 RFC 3339 date only (midnight using client local timezone)\n"+
-			"  --since 2024-05-14T22:50:00        RFC 3339 date/time using local timezone\n"+
+			"  --since 2024-05-14T22:50:00        RFC 3339 date/time using client local timezone\n"+
 			"  --since 2024-01-31T10:30:00Z       RFC 3339 date/time in UTC\n"+
 			"  --since 1763953966                 Unix timestamp (seconds since January 1, 1970)")
 	set.StringVarP(&options.Tail, "tail", "n", "100",

internal/cli/logs/time.go

@@ -0,0 +1,72 @@
+package logs
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+	"time"
+)
+
+// TimeRange resolves log filters that could be RFC 3339, timestamp, or relative duration to UTC timestamps.
+// Dates without a timezone use now's location. Relative durations are computed from now.
+func TimeRange(since, until string, now time.Time) (string, string, error) {
+	var err error
+	since, err = timestamp(since, now)
+	if err != nil {
+		return "", "", fmt.Errorf("invalid --since value: %w", err)
+	}
+	until, err = timestamp(until, now)
+	if err != nil {
+		return "", "", fmt.Errorf("invalid --until value: %w", err)
+	}
+
+	return since, until, nil
+}
+
+func timestamp(value string, now time.Time) (string, error) {
+	if value == "" {
+		return "", nil
+	}
+	// A bare zero is the Unix epoch, matching Docker's log filters.
+	if duration, err := time.ParseDuration(value); value != "0" && err == nil {
+		return now.Add(-duration).UTC().Format(time.RFC3339Nano), nil
+	}
+
+	// Keep Docker's supported date layouts, but use the location's offset at the requested date.
+	for _, layout := range []string{
+		time.RFC3339Nano,
+		"2006-01-02T15:04Z07:00",
+		"2006-01-02T15Z07:00",
+		"2006-01-02Z07:00",
+		"2006-01-02T15:04:05.999999999",
+		"2006-01-02T15:04",
+		"2006-01-02T15",
+		"2006-01-02",
+	} {
+		if t, err := time.ParseInLocation(layout, value, now.Location()); err == nil {
+			return t.UTC().Format(time.RFC3339Nano), nil
+		}
+	}
+
+	seconds, fraction, hasFraction := strings.Cut(value, ".")
+	sec, err := strconv.ParseInt(seconds, 10, 64)
+	if err != nil {
+		return "", fmt.Errorf("failed to parse '%s' as a time or duration", value)
+	}
+
+	var nsec int64
+	if hasFraction {
+		if len(fraction) == 0 || len(fraction) > 9 || strings.ContainsAny(fraction, "+-") {
+			return "", fmt.Errorf("invalid Unix timestamp fraction in '%s'", value)
+		}
+		nsec, err = strconv.ParseInt(fraction+strings.Repeat("0", 9-len(fraction)), 10, 64)
+		if err != nil {
+			return "", fmt.Errorf("invalid Unix timestamp fraction in '%s': %w", value, err)
+		}
+	}
+	t := time.Unix(sec, nsec).UTC()
+	if t.Year() < 0 || t.Year() > 9999 {
+		return "", fmt.Errorf("Unix timestamp '%s' is outside the RFC 3339 date range", value)
+	}
+	return t.Format(time.RFC3339Nano), nil
+}

internal/cli/logs/time_test.go

@@ -0,0 +1,81 @@
+package logs
+
+import (
+	"testing"
+	"time"
+
+	timetypes "github.com/docker/docker/api/types/time"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestTimeRange(t *testing.T) {
+	t.Parallel()
+
+	location, err := time.LoadLocation("Australia/Sydney")
+	require.NoError(t, err)
+	// January is daylight-saving time, but July timestamps must use the winter offset.
+	now := time.Date(2026, 1, 15, 12, 0, 0, 123456789, location)
+	tests := []struct {
+		input string
+		want  string
+	}{
+		{"", ""},
+		{"2026-07-01", "2026-06-30T14:00:00Z"},
+		{"2026-07-01T10", "2026-07-01T00:00:00Z"},
+		{"2026-07-01T10:30", "2026-07-01T00:30:00Z"},
+		{"2026-07-01T10:30:45.123456789", "2026-07-01T00:30:45.123456789Z"},
+		{"2026-01-01T10:00:00", "2025-12-31T23:00:00Z"},
+		{"2026-07-01T10:30:45Z", "2026-07-01T10:30:45Z"},
+		{"2026-07-01T10:30:45+02:00", "2026-07-01T08:30:45Z"},
+		{"2026-07-01T10:30:45-04:00", "2026-07-01T14:30:45Z"},
+		{"2026-07-01T10+02:00", "2026-07-01T08:00:00Z"},
+		{"2026-07-01T10:30+02:00", "2026-07-01T08:30:00Z"},
+		{"2026-07-01+02:00", "2026-06-30T22:00:00Z"},
+		{"1763953966", "2025-11-24T03:12:46Z"},
+		{"1763953966.000000001", "2025-11-24T03:12:46.000000001Z"},
+		{"0", "1970-01-01T00:00:00Z"},
+		{"2m30s", "2026-01-15T00:57:30.123456789Z"},
+		{"-1h", "2026-01-15T02:00:00.123456789Z"},
+	}
+	for _, tt := range tests {
+		t.Run(tt.input, func(t *testing.T) {
+			since, until, err := TimeRange(tt.input, tt.input, now)
+			require.NoError(t, err)
+			assert.Equal(t, tt.want, since)
+			assert.Equal(t, tt.want, until)
+
+			if since != "" {
+				// The server-side Docker SDK must preserve the cutoff even in another timezone.
+				actual, err := timetypes.GetTimestamp(since, now.In(time.UTC))
+				require.NoError(t, err)
+				expected, err := time.Parse(time.RFC3339Nano, tt.want)
+				require.NoError(t, err)
+				sec, nsec, err := timetypes.ParseTimestamps(actual, 0)
+				require.NoError(t, err)
+				assert.True(t, expected.Equal(time.Unix(sec, nsec)))
+			}
+		})
+	}
+
+	since, until, err := TimeRange("3h", "1h30m", now)
+	require.NoError(t, err)
+	assert.Equal(t, "2026-01-14T22:00:00.123456789Z", since)
+	assert.Equal(t, "2026-01-14T23:30:00.123456789Z", until)
+}
+
+func TestTimeRange_Invalid(t *testing.T) {
+	t.Parallel()
+
+	for _, input := range []string{
+		"invalid", "2026-02-30", "2026-01-01T25:00:00", "1763953966.xyz",
+		"1763953966.1234567890", "253402300800",
+	} {
+		t.Run(input, func(t *testing.T) {
+			_, _, err := TimeRange(input, "", time.Now())
+			require.ErrorContains(t, err, "invalid --since value")
+			_, _, err = TimeRange("", input, time.Now())
+			require.ErrorContains(t, err, "invalid --until value")
+		})
+	}
+}

internal/journal/journal.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"io"
 	"os/exec"
+	"time"
 
 	"github.com/psviderski/uncloud/pkg/api"
 )
@@ -31,11 +32,11 @@ func logs(ctx context.Context, unit string, opts api.ServiceLogsOptions) (io.Rea
 
 	if opts.Since != "" {
 		args = append(args, "-S")
-		args = append(args, opts.Since)
+		args = append(args, journalTimestamp(opts.Since))
 	}
 	if opts.Until != "" {
 		args = append(args, "-U")
-		args = append(args, opts.Until)
+		args = append(args, journalTimestamp(opts.Until))
 	}
 
 	cmd := commandContext(ctx, journalctl, args...)
@@ -51,6 +52,18 @@ func logs(ctx context.Context, unit string, opts api.ServiceLogsOptions) (io.Rea
 	return p, cmd.Wait, nil
 }
 
+// journalTimestamp formats normalised client timestamps for journalctl versions that do not
+// accept RFC 3339 timezone suffixes. Support for timestamps containing T and Z was added in
+// systemd 255 (6 December 2023). Debian 12 ships systemd 252, so it still needs this conversion.
+// Journald timestamps have microsecond precision.
+func journalTimestamp(value string) string {
+	if t, err := time.Parse(time.RFC3339Nano, value); err == nil {
+		return t.UTC().Format("2006-01-02 15:04:05.999999") + " UTC"
+	}
+	// Preserve raw filters from older clients and SDK callers.
+	return value
+}
+
 // follow synchronously follows the io.Reader, writing each new journal entry to channel.
 // It stops when the reader is exhausted or the context is cancelled.
 func follow(ctx context.Context, reader io.Reader, outCh chan api.LogEntry) {

internal/journal/logs_test.go

@@ -115,6 +115,9 @@ func TestEntry(t *testing.T) {
 }
 
 func TestLogs(t *testing.T) {
+	originalCommandContext := commandContext
+	t.Cleanup(func() { commandContext = originalCommandContext })
+
 	commandContext = func(ctx context.Context, _ string, _ ...string) *exec.Cmd {
 		return exec.CommandContext(ctx, "/usr/bin/tail", "testdata/logs")
 	}
@@ -150,3 +153,38 @@ func TestLogs(t *testing.T) {
 	// Still six because heartbeats are not written here and Tail is ignored as the command is overridden.
 	assert.Equal(t, 6, i)
 }
+
+func TestLogs_TimeFilters(t *testing.T) {
+	originalCommandContext := commandContext
+	t.Cleanup(func() { commandContext = originalCommandContext })
+
+	var args []string
+	commandContext = func(ctx context.Context, command string, commandArgs ...string) *exec.Cmd {
+		assert.Equal(t, "journalctl", command)
+		args = commandArgs
+		return exec.CommandContext(ctx, "/usr/bin/tail", "testdata/logs")
+	}
+
+	ch, err := Logs(context.Background(), "uncloud", api.ServiceLogsOptions{
+		Since: "2026-07-01T10:30:45.123456789+10:00",
+		Until: "2026-07-01T01:30:45Z",
+	})
+	require.NoError(t, err)
+	for range ch {
+	}
+	assert.Equal(t, []string{
+		"-u", "uncloud", "--no-hostname", "-n", "0", "-o", "short-unix",
+		"-S", "2026-07-01 00:30:45.123456 UTC",
+		"-U", "2026-07-01 01:30:45 UTC",
+	}, args)
+
+	// Older clients and SDK callers can still pass journalctl's native filters.
+	ch, err = Logs(context.Background(), "uncloud", api.ServiceLogsOptions{Since: "1h ago", Until: "today"})
+	require.NoError(t, err)
+	for range ch {
+	}
+	assert.Equal(t, []string{
+		"-u", "uncloud", "--no-hostname", "-n", "0", "-o", "short-unix",
+		"-S", "1h ago", "-U", "today",
+	}, args)
+}

website/docs/9-cli-reference/uc_caddy_logs.md

@@ -23,8 +23,8 @@ uc caddy logs [flags]
                           Examples:
                             --since 2m30s                      Relative duration (2 minutes 30 seconds ago)
                             --since 1h                         Relative duration (1 hour ago)
-                            --since 2025-11-24                 RFC 3339 date only (midnight using local timezone)
+                            --since 2025-11-24                 RFC 3339 date only (midnight using client local timezone)
-                            --since 2024-05-14T22:50:00        RFC 3339 date/time using local timezone
+                            --since 2024-05-14T22:50:00        RFC 3339 date/time using client local timezone
                             --since 2024-01-31T10:30:00Z       RFC 3339 date/time in UTC
                             --since 1763953966                 Unix timestamp (seconds since January 1, 1970)
   -n, --tail string       Show the most recent logs and limit the number of lines shown per replica. Use 'all' to show all logs. (default "100")

website/docs/9-cli-reference/uc_logs.md

@@ -58,8 +58,8 @@ uc logs [SERVICE[/CONTAINER]...] [flags]
                           Examples:
                             --since 2m30s                      Relative duration (2 minutes 30 seconds ago)
                             --since 1h                         Relative duration (1 hour ago)
-                            --since 2025-11-24                 RFC 3339 date only (midnight using local timezone)
+                            --since 2025-11-24                 RFC 3339 date only (midnight using client local timezone)
-                            --since 2024-05-14T22:50:00        RFC 3339 date/time using local timezone
+                            --since 2024-05-14T22:50:00        RFC 3339 date/time using client local timezone
                             --since 2024-01-31T10:30:00Z       RFC 3339 date/time in UTC
                             --since 1763953966                 Unix timestamp (seconds since January 1, 1970)
   -n, --tail string       Show the most recent logs and limit the number of lines shown per replica. Use 'all' to show all logs. (default "100")

website/docs/9-cli-reference/uc_machine_logs.md

@@ -54,8 +54,8 @@ uc machine logs [SERVICE...] [flags]
                           Examples:
                             --since 2m30s                      Relative duration (2 minutes 30 seconds ago)
                             --since 1h                         Relative duration (1 hour ago)
-                            --since 2025-11-24                 RFC 3339 date only (midnight using local timezone)
+                            --since 2025-11-24                 RFC 3339 date only (midnight using client local timezone)
-                            --since 2024-05-14T22:50:00        RFC 3339 date/time using local timezone
+                            --since 2024-05-14T22:50:00        RFC 3339 date/time using client local timezone
                             --since 2024-01-31T10:30:00Z       RFC 3339 date/time in UTC
                             --since 1763953966                 Unix timestamp (seconds since January 1, 1970)
   -n, --tail string       Show the most recent logs and limit the number of lines shown per replica. Use 'all' to show all logs. (default "100")

website/docs/9-cli-reference/uc_service_logs.md

@@ -58,8 +58,8 @@ uc service logs [SERVICE[/CONTAINER]...] [flags]
                           Examples:
                             --since 2m30s                      Relative duration (2 minutes 30 seconds ago)
                             --since 1h                         Relative duration (1 hour ago)
-                            --since 2025-11-24                 RFC 3339 date only (midnight using local timezone)
+                            --since 2025-11-24                 RFC 3339 date only (midnight using client local timezone)
-                            --since 2024-05-14T22:50:00        RFC 3339 date/time using local timezone
+                            --since 2024-05-14T22:50:00        RFC 3339 date/time using client local timezone
                             --since 2024-01-31T10:30:00Z       RFC 3339 date/time in UTC
                             --since 1763953966                 Unix timestamp (seconds since January 1, 1970)
   -n, --tail string       Show the most recent logs and limit the number of lines shown per replica. Use 'all' to show all logs. (default "100")