Alerting: Update provisioning to validate user-defined UID on create (#73793)

* add ValidateUID to util
* provisioning to validate UID on rule creation

---------

Co-authored-by: brendamuir <100768211+brendamuir@users.noreply.github.com>
Co-authored-by: Alexander Weaver <weaver.alex.d@gmail.com>

pkg/util/shortid_generator.go

@@ -1,6 +1,8 @@
 package util
 
 import (
+	"errors"
+	"fmt"
 	"math/rand"
 	"regexp"
 	"sync"
@@ -9,10 +11,18 @@ import (
 	"github.com/google/uuid"
 )
 
+const MaxUIDLength = 40
+
 var uidrand = rand.New(rand.NewSource(time.Now().UnixNano()))
 var alphaRunes = []rune("abcdefghijklmnopqrstuvwxyz")
 var hexLetters = []rune("abcdef")
 
+var (
+	ErrUIDTooLong       = fmt.Errorf("UID is longer than %d symbols", MaxUIDLength)
+	ErrUIDFormatInvalid = errors.New("invalid format of UID. Only letters, numbers, '-' and '_' are allowed")
+	ErrUIDEmpty         = fmt.Errorf("UID is empty")
+)
+
 // We want to protect our number generator as they are not thread safe. Not using
 // the mutex could result in panics in certain cases where UIDs would be generated
 // at the same time.
@@ -29,7 +39,7 @@ func IsValidShortUID(uid string) bool {
 
 // IsShortUIDTooLong checks if short unique identifier is too long
 func IsShortUIDTooLong(uid string) bool {
-	return len(uid) > 40
+	return len(uid) > MaxUIDLength
 }
 
 // GenerateShortUID will generate a UUID that can also be a k8s name
@@ -51,3 +61,17 @@ func GenerateShortUID() string {
 	}
 	return uuid
 }
+
+// ValidateUID checks the format and length of the string and returns error if it does not pass the condition
+func ValidateUID(uid string) error {
+	if len(uid) == 0 {
+		return ErrUIDEmpty
+	}
+	if IsShortUIDTooLong(uid) {
+		return ErrUIDTooLong
+	}
+	if !IsValidShortUID(uid) {
+		return ErrUIDFormatInvalid
+	}
+	return nil
+}

pkg/util/shortid_generator_test.go

@@ -4,6 +4,7 @@ import (
 	"sync"
 	"testing"
 
+	"cuelang.org/go/pkg/strings"
 	"github.com/google/uuid"
 	"github.com/stretchr/testify/require"
 	"k8s.io/apimachinery/pkg/util/validation"
@@ -84,3 +85,47 @@ func TestIsShortUIDTooLong(t *testing.T) {
 		})
 	}
 }
+
+func TestValidateUID(t *testing.T) {
+	var tests = []struct {
+		name     string
+		uid      string
+		expected error
+	}{
+		{
+			name:     "no error when string is of correct length",
+			uid:      "f8cc010c-ee72-4681-89d2-d46e1bd47d33",
+			expected: nil,
+		},
+		{
+			name:     "error when string is empty",
+			uid:      "",
+			expected: ErrUIDEmpty,
+		},
+		{
+			name:     "error when string is too long",
+			uid:      strings.Repeat("1", MaxUIDLength+1),
+			expected: ErrUIDTooLong,
+		},
+		{
+			name:     "error when string has invalid characters",
+			uid:      "f8cc010c.ee72.4681;89d2+d46e1bd47d33",
+			expected: ErrUIDFormatInvalid,
+		},
+		{
+			name:     "error when string has only whitespaces",
+			uid:      " ",
+			expected: ErrUIDFormatInvalid,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			err := ValidateUID(tt.uid)
+			if tt.expected == nil {
+				require.NoError(t, err)
+			} else {
+				require.ErrorIs(t, err, tt.expected)
+			}
+		})
+	}
+}