feat: add frontend + backend + database to retrieve and compute news from Yahoo

backend/internal/crypto/aes.go

@@ -0,0 +1,59 @@
+package crypto
+
+import (
+	"crypto/aes"
+	"crypto/cipher"
+	"crypto/rand"
+	"encoding/base64"
+	"fmt"
+	"io"
+)
+
+type Encryptor struct {
+	key []byte
+}
+
+func New(key []byte) *Encryptor {
+	return &Encryptor{key: key}
+}
+
+func (e *Encryptor) Encrypt(plaintext string) (string, error) {
+	block, err := aes.NewCipher(e.key)
+	if err != nil {
+		return "", err
+	}
+	gcm, err := cipher.NewGCM(block)
+	if err != nil {
+		return "", err
+	}
+	nonce := make([]byte, gcm.NonceSize())
+	if _, err = io.ReadFull(rand.Reader, nonce); err != nil {
+		return "", err
+	}
+	ciphertext := gcm.Seal(nonce, nonce, []byte(plaintext), nil)
+	return base64.StdEncoding.EncodeToString(ciphertext), nil
+}
+
+func (e *Encryptor) Decrypt(encoded string) (string, error) {
+	data, err := base64.StdEncoding.DecodeString(encoded)
+	if err != nil {
+		return "", err
+	}
+	block, err := aes.NewCipher(e.key)
+	if err != nil {
+		return "", err
+	}
+	gcm, err := cipher.NewGCM(block)
+	if err != nil {
+		return "", err
+	}
+	if len(data) < gcm.NonceSize() {
+		return "", fmt.Errorf("ciphertext too short")
+	}
+	nonce, ciphertext := data[:gcm.NonceSize()], data[gcm.NonceSize():]
+	plain, err := gcm.Open(nil, nonce, ciphertext, nil)
+	if err != nil {
+		return "", err
+	}
+	return string(plain), nil
+}