utils: ConvertToBytes

utils/README.md

@@ -84,4 +84,7 @@ Benchmark_Trim/default-16                       18457221                 66.0 ns
 Benchmark_Trim/default-16                       18177328                 65.9 ns/op           32 B/op          1 allocs/op
 Benchmark_Trim/default.trimspace-16            188933770                 6.33 ns/op            0 B/op          0 allocs/op
 Benchmark_Trim/default.trimspace-16            184007649                 6.42 ns/op            0 B/op          0 allocs/op
+
+Benchmark_ConvertToBytes/fiber-12               32883782                33.76 ns/op            0 B/op          0 allocs/op
+Benchmark_ConvertToBytes/fiber-12               36084900                33.47 ns/op            0 B/op          0 allocs/op
 ```

utils/common.go

@@ -8,20 +8,26 @@ import (
 	"crypto/rand"
 	"encoding/binary"
 	"encoding/hex"
-
 	"net"
 	"os"
 	"reflect"
 	"runtime"
+	"strconv"
 	"sync"
 	"sync/atomic"
+	"unicode"
 
 	googleuuid "github.com/gofiber/fiber/v2/internal/uuid"
 )
 
 const (
 	toLowerTable = "\x00\x01\x02\x03\x04\x05\x06\a\b\t\n\v\f\r\x0e\x0f\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f !\"#$%&'()*+,-./0123456789:;<=>?@abcdefghijklmnopqrstuvwxyz[\\]^_`abcdefghijklmnopqrstuvwxyz{|}~\u007f\x80\x81\x82\x83\x84\x85\x86\x87\x88\x89\x8a\x8b\x8c\x8d\x8e\x8f\x90\x91\x92\x93\x94\x95\x96\x97\x98\x99\x9a\x9b\x9c\x9d\x9e\x9f\xa0\xa1\xa2\xa3\xa4\xa5\xa6\xa7\xa8\xa9\xaa\xab\xac\xad\xae\xaf\xb0\xb1\xb2\xb3\xb4\xb5\xb6\xb7\xb8\xb9\xba\xbb\xbc\xbd\xbe\xbf\xc0\xc1\xc2\xc3\xc4\xc5\xc6\xc7\xc8\xc9\xca\xcb\xcc\xcd\xce\xcf\xd0\xd1\xd2\xd3\xd4\xd5\xd6\xd7\xd8\xd9\xda\xdb\xdc\xdd\xde\xdf\xe0\xe1\xe2\xe3\xe4\xe5\xe6\xe7\xe8\xe9\xea\xeb\xec\xed\xee\xef\xf0\xf1\xf2\xf3\xf4\xf5\xf6\xf7\xf8\xf9\xfa\xfb\xfc\xfd\xfe\xff"
 	toUpperTable = "\x00\x01\x02\x03\x04\x05\x06\a\b\t\n\v\f\r\x0e\x0f\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f !\"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_`ABCDEFGHIJKLMNOPQRSTUVWXYZ{|}~\u007f\x80\x81\x82\x83\x84\x85\x86\x87\x88\x89\x8a\x8b\x8c\x8d\x8e\x8f\x90\x91\x92\x93\x94\x95\x96\x97\x98\x99\x9a\x9b\x9c\x9d\x9e\x9f\xa0\xa1\xa2\xa3\xa4\xa5\xa6\xa7\xa8\xa9\xaa\xab\xac\xad\xae\xaf\xb0\xb1\xb2\xb3\xb4\xb5\xb6\xb7\xb8\xb9\xba\xbb\xbc\xbd\xbe\xbf\xc0\xc1\xc2\xc3\xc4\xc5\xc6\xc7\xc8\xc9\xca\xcb\xcc\xcd\xce\xcf\xd0\xd1\xd2\xd3\xd4\xd5\xd6\xd7\xd8\xd9\xda\xdb\xdc\xdd\xde\xdf\xe0\xe1\xe2\xe3\xe4\xe5\xe6\xe7\xe8\xe9\xea\xeb\xec\xed\xee\xef\xf0\xf1\xf2\xf3\xf4\xf5\xf6\xf7\xf8\xf9\xfa\xfb\xfc\xfd\xfe\xff"
+	kb           = 1000
+	mb           = 1000 * kb
+	gb           = 1000 * mb
+	tb           = 1000 * gb
+	pb           = 1000 * tb
 )
 
 // Copyright © 2014, Roger Peppe
@@ -32,6 +38,7 @@ var (
 	uuidSeed    [24]byte
 	uuidCounter uint64
 	uuidSetup   sync.Once
+	unitsMap    = map[byte]int64{'k': kb, 'm': mb, 'g': gb, 't': tb, 'p': pb}
 )
 
 // UUID generates an universally unique identifier (UUID)
@@ -109,3 +116,39 @@ func IncrementIPRange(ip net.IP) {
 		}
 	}
 }
+
+// ConvertToBytes returns integer size of bytes from human-readable string, ex. 42kb, 42M
+// Returns 0 if string is unrecognized
+func ConvertToBytes(humanReadableString string) int {
+	var unitPrefixPos, lastNumberPos int
+	strLen := len(humanReadableString)
+	// loop the string
+	for i := strLen - 1; i >= 0; i-- {
+		// check if the char is a number
+		if unicode.IsDigit(rune(humanReadableString[i])) {
+			lastNumberPos = i
+			break
+		} else if humanReadableString[i] != ' ' {
+			unitPrefixPos = i
+		}
+	}
+
+	if lastNumberPos < 0 {
+		return 0
+	}
+	// fetch the number part and parse it to float
+	size, err := strconv.ParseFloat(humanReadableString[:lastNumberPos+1], 64)
+	if err != nil {
+		return 0
+	}
+
+	// check the muliplicator from the string and use it
+	if unitPrefixPos > 0 {
+		// convert multiplication char to lowercase and check the table
+		if mul, ok := unitsMap[toLowerTable[humanReadableString[unitPrefixPos]]]; ok {
+			size *= float64(mul)
+		}
+	}
+
+	return int(size)
+}

utils/common_test.go

@@ -89,3 +89,37 @@ func Benchmark_UUID(b *testing.B) {
 		AssertEqual(b, 36, len(res))
 	})
 }
+
+func Test_ConvertToBytes(t *testing.T) {
+	t.Parallel()
+	AssertEqual(t, 42, ConvertToBytes("42"))
+	AssertEqual(t, 42, ConvertToBytes("42b"))
+	AssertEqual(t, 42, ConvertToBytes("42B"))
+	AssertEqual(t, 42, ConvertToBytes("42 b"))
+	AssertEqual(t, 42, ConvertToBytes("42 B"))
+
+	AssertEqual(t, 42*1000, ConvertToBytes("42k"))
+	AssertEqual(t, 42*1000, ConvertToBytes("42K"))
+	AssertEqual(t, 42*1000, ConvertToBytes("42kb"))
+	AssertEqual(t, 42*1000, ConvertToBytes("42KB"))
+	AssertEqual(t, 42*1000, ConvertToBytes("42 kb"))
+	AssertEqual(t, 42*1000, ConvertToBytes("42 KB"))
+
+	AssertEqual(t, 42*1000000, ConvertToBytes("42M"))
+	AssertEqual(t, int(42.5*1000000), ConvertToBytes("42.5MB"))
+	AssertEqual(t, 42*1000000000, ConvertToBytes("42G"))
+
+	AssertEqual(t, 0, ConvertToBytes("string"))
+	AssertEqual(t, 0, ConvertToBytes("MB"))
+}
+
+// go test -v -run=^$ -bench=Benchmark_ConvertToBytes -benchmem -count=2
+func Benchmark_ConvertToBytes(b *testing.B) {
+	var res int
+	b.Run("fiber", func(b *testing.B) {
+		for n := 0; n < b.N; n++ {
+			res = ConvertToBytes("42B")
+		}
+		AssertEqual(b, 42, res)
+	})
+}