[#275] added support to customize the default user email templates from the Admin UI

tools/security/random.go

@@ -4,15 +4,23 @@ import (
 	"crypto/rand"
 )
 
-// RandomString generates a random string of specified length.
+// RandomString generates a random string with the specified length.
 //
 // The generated string is cryptographically random and matches
 // [A-Za-z0-9]+ (aka. it's transparent to URL-encoding).
 func RandomString(length int) string {
 	const alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"
 
+	return RandomStringWithAlphabet(length, alphabet)
+}
+
+// RandomStringWithAlphabet generates a cryptographically random string
+// with the specified length and characters set.
+func RandomStringWithAlphabet(length int, alphabet string) string {
 	bytes := make([]byte, length)
+
 	rand.Read(bytes)
+
 	for i, b := range bytes {
 		bytes[i] = alphabet[b%byte(len(alphabet))]
 	}

tools/security/random_test.go

@@ -10,25 +10,62 @@ import (
 func TestRandomString(t *testing.T) {
 	generated := []string{}
 	reg := regexp.MustCompile(`[a-zA-Z0-9]+`)
+	length := 10
 
-	for i := 0; i < 30; i++ {
-		length := 5 + i
+	for i := 0; i < 100; i++ {
 		result := security.RandomString(length)
 
 		if len(result) != length {
-			t.Errorf("(%d) Expected the length of the string to be %d, got %d", i, length, len(result))
+			t.Fatalf("(%d) Expected the length of the string to be %d, got %d", i, length, len(result))
 		}
 
 		if match := reg.MatchString(result); !match {
-			t.Errorf("(%d) The generated strings should have only [a-zA-Z0-9]+ characters, got %q", i, result)
+			t.Fatalf("(%d) The generated string should have only [a-zA-Z0-9]+ characters, got %q", i, result)
 		}
 
 		for _, str := range generated {
 			if str == result {
-				t.Errorf("(%d) Repeating random string - found %q in \n%v", i, result, generated)
+				t.Fatalf("(%d) Repeating random string - found %q in \n%v", i, result, generated)
 			}
 		}
 
 		generated = append(generated, result)
 	}
 }
+
+func TestRandomStringWithAlphabet(t *testing.T) {
+	scenarios := []struct {
+		alphabet      string
+		expectPattern string
+	}{
+		{"0123456789_", `[0-9_]+`},
+		{"abcd", `[abcd]+`},
+		{"!@#$%^&*()", `[\!\@\#\$\%\^\&\*\(\)]+`},
+	}
+
+	for i, s := range scenarios {
+		generated := make([]string, 100)
+		length := 10
+
+		for j := 0; j < 100; j++ {
+			result := security.RandomStringWithAlphabet(length, s.alphabet)
+
+			if len(result) != length {
+				t.Fatalf("(%d:%d) Expected the length of the string to be %d, got %d", i, j, length, len(result))
+			}
+
+			reg := regexp.MustCompile(s.expectPattern)
+			if match := reg.MatchString(result); !match {
+				t.Fatalf("(%d:%d) The generated string should have only %s characters, got %q", i, j, s.expectPattern, result)
+			}
+
+			for _, str := range generated {
+				if str == result {
+					t.Fatalf("(%d:%d) Repeating random string - found %q in %q", i, j, result, generated)
+				}
+			}
+
+			generated = append(generated, result)
+		}
+	}
+}