db: add tests for two factors (#6099)

* Rename to TwoFactors.Create

* Use GORM to execute queries

* TwoFactor.GetByUserID

* Add tests

* Fix failing tests

* Add MD5 tests

* Add tests for RandomChars

2 files changed, 43 insertions, 0 deletions

diff --git a/internal/strutil/strutil.go b/internal/strutil/strutil.go
index a2b84a20..b1de241f 100644
--- a/internal/strutil/strutil.go
+++ b/internal/strutil/strutil.go
@@ -5,6 +5,8 @@
 package strutil
 
 import (
+	"crypto/rand"
+	"math/big"
 	"unicode"
 )
 
@@ -15,3 +17,30 @@ func ToUpperFirst(s string) string {
 	}
 	return ""
 }
+
+// RandomChars returns a generated string in given number of random characters.
+func RandomChars(n int) (string, error) {
+	const alphanum = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"
+
+	randomInt := func(max *big.Int) (int, error) {
+		r, err := rand.Int(rand.Reader, max)
+		if err != nil {
+			return 0, err
+		}
+
+		return int(r.Int64()), nil
+	}
+
+	buffer := make([]byte, n)
+	max := big.NewInt(int64(len(alphanum)))
+	for i := 0; i < n; i++ {
+		index, err := randomInt(max)
+		if err != nil {
+			return "", err
+		}
+
+		buffer[i] = alphanum[index]
+	}
+
+	return string(buffer), nil
+}
diff --git a/internal/strutil/strutil_test.go b/internal/strutil/strutil_test.go
index d603533b..c4edf140 100644
--- a/internal/strutil/strutil_test.go
+++ b/internal/strutil/strutil_test.go
@@ -41,3 +41,17 @@ func TestToUpperFirst(t *testing.T) {
 		})
 	}
 }
+
+func TestRandomChars(t *testing.T) {
+	cache := make(map[string]bool)
+	for i := 0; i < 100; i++ {
+		chars, err := RandomChars(10)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if cache[chars] {
+			t.Fatalf("Duplicated chars %q", chars)
+		}
+		cache[chars] = true
+	}
+}