Add sqlserverflex instance (#381)

* Draft implementation sqlserverflex instance

* Finish implementation

* Fix acc test

* Changes after review

stackit/internal/utils/utils.go

@@ -2,6 +2,8 @@ package utils
 
 import (
 	"fmt"
+	"regexp"
+	"strings"
 
 	"github.com/hashicorp/terraform-plugin-framework/types/basetypes"
 
@@ -60,3 +62,17 @@ func ListValuetoStringSlice(list basetypes.ListValue) ([]string, error) {
 
 	return result, nil
 }
+
+// Remove leading 0s from backup schedule numbers (e.g. "00 00 * * *" becomes "0 0 * * *")
+// Needed as the API does it internally and would otherwise cause inconsistent result in Terraform
+func SimplifyBackupSchedule(schedule string) string {
+	regex := regexp.MustCompile(`0+\d+`) // Matches series of one or more zeros followed by a series of one or more digits
+	simplifiedSchedule := regex.ReplaceAllStringFunc(schedule, func(match string) string {
+		simplified := strings.TrimLeft(match, "0")
+		if simplified == "" {
+			simplified = "0"
+		}
+		return simplified
+	})
+	return simplifiedSchedule
+}

stackit/internal/utils/utils_test.go

@@ -120,3 +120,75 @@ func TestListValuetoStrSlice(t *testing.T) {
 		})
 	}
 }
+
+func TestSimplifyBackupSchedule(t *testing.T) {
+	tests := []struct {
+		description string
+		input       string
+		expected    string
+	}{
+		{
+			"simple schedule",
+			"0 0 * * *",
+			"0 0 * * *",
+		},
+		{
+			"schedule with leading zeros",
+			"00 00 * * *",
+			"0 0 * * *",
+		},
+		{
+			"schedule with leading zeros 2",
+			"00 001 * * *",
+			"0 1 * * *",
+		},
+		{
+			"schedule with leading zeros 3",
+			"00 0010 * * *",
+			"0 10 * * *",
+		},
+		{
+			"simple schedule with slash",
+			"0 0/6 * * *",
+			"0 0/6 * * *",
+		},
+		{
+			"schedule with leading zeros and slash",
+			"00 00/6 * * *",
+			"0 0/6 * * *",
+		},
+		{
+			"schedule with leading zeros and slash 2",
+			"00 001/06 * * *",
+			"0 1/6 * * *",
+		},
+		{
+			"simple schedule with comma",
+			"0 10,15 * * *",
+			"0 10,15 * * *",
+		},
+		{
+			"schedule with leading zeros and comma",
+			"0 010,0015 * * *",
+			"0 10,15 * * *",
+		},
+		{
+			"simple schedule with comma and slash",
+			"0 0-11/10 * * *",
+			"0 0-11/10 * * *",
+		},
+		{
+			"schedule with leading zeros, comma, and slash",
+			"00 000-011/010 * * *",
+			"0 0-11/10 * * *",
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.description, func(t *testing.T) {
+			output := SimplifyBackupSchedule(tt.input)
+			if output != tt.expected {
+				t.Fatalf("Data does not match: %s", output)
+			}
+		})
+	}
+}