The PlantUML encoder written by Go

plantuml_encoder.go

package pumlencode

import (
    "bytes"
    "compress/zlib"
    "encoding/base64"
)

func makeTable() map[rune]rune {
    src := []rune{}
    for r := 'A'; r <= 'Z'; r++ {
        src = append(src, r)
    }
    for r := 'a'; r <= 'z'; r++ {
        src = append(src, r)
    }
    for r := '0'; r <= '9'; r++ {
        src = append(src, r)
    }
    src = append(src, '+')
    src = append(src, '/')

    dst := []rune{}
    for r := '0'; r <= '9'; r++ {
        dst = append(dst, r)
    }
    for r := 'A'; r <= 'Z'; r++ {
        dst = append(dst, r)
    }
    for r := 'a'; r <= 'z'; r++ {
        dst = append(dst, r)
    }
    dst = append(dst, '-')
    dst = append(dst, '_')

    ret := map[rune]rune{}
    for i := 0; i < len(src); i++ {
        ret[src[i]] = dst[i]
    }

    return ret
}

var transTable = makeTable()

func translate(table map[rune]rune, str string) string {
    ret := []rune{}
    for _, char := range []rune(str) {
        ret = append(ret, table[char])
    }
    return string(ret)
}

// Encode generates and returns PlantUML text encode string from the given PlantUML code.
func Encode(plantUMLCode string) string {
    b := new(bytes.Buffer)
    w := zlib.NewWriter(b)
    w.Write([]byte(plantUMLCode))
    w.Close()
    compressedStr := b.Bytes()[2 : b.Len()-4]

    b = new(bytes.Buffer)
    encoder := base64.NewEncoder(base64.StdEncoding, b)
    encoder.Write(compressedStr)
    encoder.Close()
    return translate(transTable, b.String())
}