add unit testing for crypto package

pkg/crypto/aes_test.go

@@ -0,0 +1,68 @@
+package crypto
+
+import (
+	"encoding/base64"
+	"github.com/stretchr/testify/require"
+	"testing"
+)
+
+func Test_General(t *testing.T) {
+	req := require.New(t)
+	// ensure that it works the first time
+	req.NoError(NewAESCipher())
+	cipherKey := ToString()
+
+	// ensure that values that are encrypted can be decrypted again
+	testValue := "this is a test value"
+	testEncrypted := Encrypt([]byte(testValue))
+	testDecrypted, err := Decrypt(testEncrypted)
+	req.NoError(err)
+	req.NotEqual(testValue, string(testEncrypted))
+	req.Equal(testValue, string(testDecrypted))
+
+	// ensure that rerunning it does not cause an error or change the cipherKey
+	req.NoError(NewAESCipher())
+	newCipherKey := ToString()
+	req.Equal(cipherKey, newCipherKey)
+
+	testDecrypted, err = Decrypt(testEncrypted)
+	req.NoError(err)
+	req.Equal(testValue, string(testDecrypted))
+
+	// ensure that string values of the cipherKey can be added
+	err = InitFromString(cipherKey)
+	req.NoError(err)
+
+	// ensure that empty string values passed to InitFromString are accepted
+	err = InitFromString("")
+	req.NoError(err)
+
+	// ensure that invalid (non-empty) string values passed to InitFromString fail
+	err = InitFromString("not a key")
+	req.Error(err)
+	err = InitFromString(base64.StdEncoding.EncodeToString([]byte("still not a key")))
+	req.Error(err)
+
+	// ensure that string values of other ciphers can be added and used
+	altCipher := "wwYTl3RHaCirSqx7alC/hsRQXyycHDdGZZCyNMy9R01p5czC"
+	altCiphertext := "sNrI1egS1iLGesPDecd8G7WoNyE/KL7IFR6mYPzWwZLY5xCC"
+	altPlaintext := "this is a test value"
+	req.NotEqual(cipherKey, altCipher) // a new randomly generated cipherText should not match this one
+
+	err = InitFromString(altCipher)
+	req.NoError(err)
+
+	altCipherBytes, err := base64.StdEncoding.DecodeString(altCiphertext)
+	req.NoError(err)
+
+	altDecrypted, err := Decrypt(altCipherBytes)
+	req.NoError(err)
+	req.Equal(altPlaintext, string(altDecrypted))
+
+	// ensure that after adding a new key, the original key is still used for encryption and decryption
+	testReEncrypted := Encrypt([]byte(testValue))
+	req.Equal(string(testEncrypted), string(testReEncrypted))
+	testDecrypted, err = Decrypt(testEncrypted)
+	req.NoError(err)
+	req.Equal(testValue, string(testDecrypted))
+}