feat: add time helpers

Signed-off-by: Techno Freak <freak12techno@gmail.com>

template/template.go

@@ -15,13 +15,16 @@ package template
 
 import (
 	"bytes"
+	"fmt"
 	tmplhtml "html/template"
 	"io"
+	"math"
 	"net/url"
 	"path"
 	"path/filepath"
 	"regexp"
 	"sort"
+	"strconv"
 	"strings"
 	tmpltext "text/template"
 	"time"
@@ -192,6 +195,74 @@ var DefaultFuncs = FuncMap{
 	"stringSlice": func(s ...string) []string {
 		return s
 	},
+	"since": time.Since,
+	"humanizeDuration": func(i interface{}) (string, error) {
+		v, err := convertToFloat(i)
+		if err != nil {
+			return "", err
+		}
+
+		if math.IsNaN(v) || math.IsInf(v, 0) {
+			return fmt.Sprintf("%.4g", v), nil
+		}
+		if v == 0 {
+			return fmt.Sprintf("%.4gs", v), nil
+		}
+		if math.Abs(v) >= 1 {
+			sign := ""
+			if v < 0 {
+				sign = "-"
+				v = -v
+			}
+			duration := int64(v)
+			seconds := duration % 60
+			minutes := (duration / 60) % 60
+			hours := (duration / 60 / 60) % 24
+			days := duration / 60 / 60 / 24
+			// For days to minutes, we display seconds as an integer.
+			if days != 0 {
+				return fmt.Sprintf("%s%dd %dh %dm %ds", sign, days, hours, minutes, seconds), nil
+			}
+			if hours != 0 {
+				return fmt.Sprintf("%s%dh %dm %ds", sign, hours, minutes, seconds), nil
+			}
+			if minutes != 0 {
+				return fmt.Sprintf("%s%dm %ds", sign, minutes, seconds), nil
+			}
+			// For seconds, we display 4 significant digits.
+			return fmt.Sprintf("%s%.4gs", sign, v), nil
+		}
+		prefix := ""
+		for _, p := range []string{"m", "u", "n", "p", "f", "a", "z", "y"} {
+			if math.Abs(v) >= 1 {
+				break
+			}
+			prefix = p
+			v *= 1000
+		}
+		return fmt.Sprintf("%.4g%ss", v, prefix), nil
+	},
+}
+
+func convertToFloat(i interface{}) (float64, error) {
+	switch v := i.(type) {
+	case float64:
+		return v, nil
+	case string:
+		return strconv.ParseFloat(v, 64)
+	case int:
+		return float64(v), nil
+	case uint:
+		return float64(v), nil
+	case int64:
+		return float64(v), nil
+	case uint64:
+		return float64(v), nil
+	case time.Duration:
+		return v.Seconds(), nil
+	default:
+		return 0, fmt.Errorf("can't convert %T to float", v)
+	}
 }
 
 // Pair is a key/value string pair.

template/template_test.go

@@ -385,6 +385,53 @@ func TestTemplateExpansion(t *testing.T) {
 			},
 			exp: "[key2 key4]",
 		},
+		{
+			title: "Template using HumanizeDuration - seconds - float64",
+			in:    "{{ range . }}{{ humanizeDuration . }}:{{ end }}",
+			data:  []float64{0, 1, 60, 3600, 86400, 86400 + 3600, -(86400*2 + 3600*3 + 60*4 + 5), 899.99},
+			exp:   "0s:1s:1m 0s:1h 0m 0s:1d 0h 0m 0s:1d 1h 0m 0s:-2d 3h 4m 5s:14m 59s:",
+		},
+		{
+			title: "Template using HumanizeDuration - seconds - string.",
+			in:    "{{ range . }}{{ humanizeDuration . }}:{{ end }}",
+			data:  []string{"0", "1", "60", "3600", "86400"},
+			exp:   "0s:1s:1m 0s:1h 0m 0s:1d 0h 0m 0s:",
+		},
+		{
+			title: "Template using HumanizeDuration - subsecond and fractional seconds - float64.",
+			in:    "{{ range . }}{{ humanizeDuration . }}:{{ end }}",
+			data:  []float64{.1, .0001, .12345, 60.1, 60.5, 1.2345, 12.345},
+			exp:   "100ms:100us:123.5ms:1m 0s:1m 0s:1.234s:12.35s:",
+		},
+		{
+			title: "Template using HumanizeDuration - subsecond and fractional seconds - string.",
+			in:    "{{ range . }}{{ humanizeDuration . }}:{{ end }}",
+			data:  []string{".1", ".0001", ".12345", "60.1", "60.5", "1.2345", "12.345"},
+			exp:   "100ms:100us:123.5ms:1m 0s:1m 0s:1.234s:12.35s:",
+		},
+		{
+			title: "Template using HumanizeDuration - string with error.",
+			in:    `{{ humanizeDuration "one" }}`,
+			fail:  true,
+		},
+		{
+			title: "Template using HumanizeDuration - int.",
+			in:    "{{ range . }}{{ humanizeDuration . }}:{{ end }}",
+			data:  []int{0, -1, 1, 1234567},
+			exp:   "0s:-1s:1s:14d 6h 56m 7s:",
+		},
+		{
+			title: "Template using HumanizeDuration - uint.",
+			in:    "{{ range . }}{{ humanizeDuration . }}:{{ end }}",
+			data:  []uint{0, 1, 1234567},
+			exp:   "0s:1s:14d 6h 56m 7s:",
+		},
+		{
+			title: "Template using since",
+			in:    "{{ . | since | humanizeDuration }}",
+			data:  time.Now().Add(-1 * time.Hour),
+			exp:   "1h 0m 0s",
+		},
 	} {
 		tc := tc
 		t.Run(tc.title, func(t *testing.T) {