Show download count info in release list (#10124)

* Show download count info in release list

* Use go-humanize

vendor/github.com/dustin/go-humanize/bytes.go

@@ -0,0 +1,143 @@
+package humanize
+
+import (
+	"fmt"
+	"math"
+	"strconv"
+	"strings"
+	"unicode"
+)
+
+// IEC Sizes.
+// kibis of bits
+const (
+	Byte = 1 << (iota * 10)
+	KiByte
+	MiByte
+	GiByte
+	TiByte
+	PiByte
+	EiByte
+)
+
+// SI Sizes.
+const (
+	IByte = 1
+	KByte = IByte * 1000
+	MByte = KByte * 1000
+	GByte = MByte * 1000
+	TByte = GByte * 1000
+	PByte = TByte * 1000
+	EByte = PByte * 1000
+)
+
+var bytesSizeTable = map[string]uint64{
+	"b":   Byte,
+	"kib": KiByte,
+	"kb":  KByte,
+	"mib": MiByte,
+	"mb":  MByte,
+	"gib": GiByte,
+	"gb":  GByte,
+	"tib": TiByte,
+	"tb":  TByte,
+	"pib": PiByte,
+	"pb":  PByte,
+	"eib": EiByte,
+	"eb":  EByte,
+	// Without suffix
+	"":   Byte,
+	"ki": KiByte,
+	"k":  KByte,
+	"mi": MiByte,
+	"m":  MByte,
+	"gi": GiByte,
+	"g":  GByte,
+	"ti": TiByte,
+	"t":  TByte,
+	"pi": PiByte,
+	"p":  PByte,
+	"ei": EiByte,
+	"e":  EByte,
+}
+
+func logn(n, b float64) float64 {
+	return math.Log(n) / math.Log(b)
+}
+
+func humanateBytes(s uint64, base float64, sizes []string) string {
+	if s < 10 {
+		return fmt.Sprintf("%d B", s)
+	}
+	e := math.Floor(logn(float64(s), base))
+	suffix := sizes[int(e)]
+	val := math.Floor(float64(s)/math.Pow(base, e)*10+0.5) / 10
+	f := "%.0f %s"
+	if val < 10 {
+		f = "%.1f %s"
+	}
+
+	return fmt.Sprintf(f, val, suffix)
+}
+
+// Bytes produces a human readable representation of an SI size.
+//
+// See also: ParseBytes.
+//
+// Bytes(82854982) -> 83 MB
+func Bytes(s uint64) string {
+	sizes := []string{"B", "kB", "MB", "GB", "TB", "PB", "EB"}
+	return humanateBytes(s, 1000, sizes)
+}
+
+// IBytes produces a human readable representation of an IEC size.
+//
+// See also: ParseBytes.
+//
+// IBytes(82854982) -> 79 MiB
+func IBytes(s uint64) string {
+	sizes := []string{"B", "KiB", "MiB", "GiB", "TiB", "PiB", "EiB"}
+	return humanateBytes(s, 1024, sizes)
+}
+
+// ParseBytes parses a string representation of bytes into the number
+// of bytes it represents.
+//
+// See Also: Bytes, IBytes.
+//
+// ParseBytes("42 MB") -> 42000000, nil
+// ParseBytes("42 mib") -> 44040192, nil
+func ParseBytes(s string) (uint64, error) {
+	lastDigit := 0
+	hasComma := false
+	for _, r := range s {
+		if !(unicode.IsDigit(r) || r == '.' || r == ',') {
+			break
+		}
+		if r == ',' {
+			hasComma = true
+		}
+		lastDigit++
+	}
+
+	num := s[:lastDigit]
+	if hasComma {
+		num = strings.Replace(num, ",", "", -1)
+	}
+
+	f, err := strconv.ParseFloat(num, 64)
+	if err != nil {
+		return 0, err
+	}
+
+	extra := strings.ToLower(strings.TrimSpace(s[lastDigit:]))
+	if m, ok := bytesSizeTable[extra]; ok {
+		f *= float64(m)
+		if f >= math.MaxUint64 {
+			return 0, fmt.Errorf("too large: %v", s)
+		}
+		return uint64(f), nil
+	}
+
+	return 0, fmt.Errorf("unhandled size name: %v", extra)
+}