To create a program in Go that can encode and decode Base64 and URL, follow these steps:
Step 1: Initialize the Go Module
First, create a new directory for your project and initialize the Go module.
mkdir encoder_decoder
cd encoder_decoder
mkdir lib
go mod init github.com/username/encoder_decoder
Step 2: Create the encoder.go File
Create an lib/encodedecode.go file to handle the encoding and decoding functionality.
// encodedecode.go
package lib
import (
"encoding/base64"
"net/url"
)
// Base64Encode encodes a string to Base64.
func Base64Encode(data string) string {
return base64.StdEncoding.EncodeToString([]byte(data))
}
// Base64Decode decodes a Base64 string.
func Base64Decode(data string) (string, error) {
decoded, err := base64.StdEncoding.DecodeString(data)
if err != nil {
return "", err
}
return string(decoded), nil
}
// URLEncode encodes a string to URL encoding.
func URLEncode(data string) string {
return url.QueryEscape(data)
}
// URLDecode decodes a URL encoded string.
func URLDecode(data string) (string, error) {
decoded, err := url.QueryUnescape(data)
if err != nil {
return "", err
}
return decoded, nil
}
Step 3: Create the main.go File
Create a main.go file to use the encoding and decoding functionality.
package main
import (
"bufio"
"flag"
"fmt"
"io"
"os"
"github.com/username/encodedecode/lib"
)
func main() {
mode := flag.String("mode", "encode", "Mode: encode or decode")
method := flag.String("method", "base64", "Method: base64 or url")
input := flag.String("input", "", "Input string")
filePath := flag.String("file", "", "Path to input file")
flag.Parse()
var data string
if *filePath != "" {
// Read from file
file, err := os.Open(*filePath)
if err != nil {
fmt.Printf("Error opening file: %v\n", err)
os.Exit(1)
}
defer file.Close()
reader := bufio.NewReader(file)
inputBytes, err := io.ReadAll(reader)
if err != nil {
fmt.Printf("Error reading file: %v\n", err)
os.Exit(1)
}
data = string(inputBytes)
} else if *input == "" {
// Check if input is coming from a pipe
fi, err := os.Stdin.Stat()
if err != nil {
fmt.Printf("Error: %v\n", err)
os.Exit(1)
}
if fi.Mode()&os.ModeNamedPipe != 0 {
// Read from stdin
reader := bufio.NewReader(os.Stdin)
inputBytes, err := io.ReadAll(reader)
if err != nil {
fmt.Printf("Error reading from stdin: %v\n", err)
os.Exit(1)
}
data = string(inputBytes)
} else {
fmt.Println("Enter input string:")
scanner := bufio.NewScanner(os.Stdin)
if scanner.Scan() {
data = scanner.Text()
}
}
} else {
data = *input
}
var result string
var err error
switch *method {
case "base64":
if *mode == "encode" {
result = lib.Base64Encode(data)
} else {
result, err = lib.Base64Decode(data)
}
case "url":
if *mode == "encode" {
result = lib.URLEncode(data)
} else {
result, err = lib.URLDecode(data)
}
default:
fmt.Println("Unsupported method. Use 'base64' or 'url'.")
os.Exit(1)
}
if err != nil {
fmt.Printf("Error: %v\n", err)
os.Exit(1)
}
fmt.Println(result)
}
Step 4: Run the Program
Run the program using the go run command.
To encode a string to Base64:
go run main.go --mode encode --method base64 --input "Hello, World!"
To decode a Base64 string:
go run main.go --mode decode --method base64 --input "SGVsbG8sIFdvcmxkIQ=="
To encode a string to URL encoding:
go run main.go --mode encode --method url --input "Hello, World!"
To decode a URL encoded string:
go run main.go --mode decode --method url --input "Hello%2C+World%21"
This will encode or decode the input string based on the specified mode and method.
Example for Piped Data
To encode data piped from another command to Base64:
echo "Hello, World!" | go run main.go --mode encode --method base64
To decode Base64 data piped from another command:
echo "SGVsbG8sIFdvcmxkIQ==" | go run main.go --mode decode --method base64
To encode data piped from another command to URL encoding:
echo "Hello, World!" | go run main.go --mode encode --method url
To decode URL encoded data piped from another command:
echo "Hello%2C+World%21" | go run main.go --mode decode --method url
Example for Data Read from File
To encode data read from a file to Base64:
go run main.go --mode encode --method base64 --file path/to/input.txt
To decode Base64 data read from a file:
go run main.go --mode decode --method base64 --file path/to/input.txt
To encode data read from a file to URL encoding:
go run main.go --mode encode --method url --file path/to/input.txt
To decode URL encoded data read from a file:
go run main.go --mode decode --method url --file path/to/input.txt
Example with default values
The default mode is encode and the default method is base64. If no input is provided, the program will prompt for input.
To enter input manually:
go run main.go
To base64 encode a file:
cat path/to/input.txt | go run main.go
Last modified: 08 January 2025