Adding upstream version 0.28.1.

Signed-off-by: Daniel Baumann <daniel@debian.org>

core/validators/db.go

@@ -0,0 +1,80 @@
+package validators
+
+import (
+	"database/sql"
+	"errors"
+	"strings"
+
+	validation "github.com/go-ozzo/ozzo-validation/v4"
+	"github.com/pocketbase/dbx"
+)
+
+// UniqueId checks whether a field string id already exists in the specified table.
+//
+// Example:
+//
+//	validation.Field(&form.RelId, validation.By(validators.UniqueId(form.app.DB(), "tbl_example"))
+func UniqueId(db dbx.Builder, tableName string) validation.RuleFunc {
+	return func(value any) error {
+		v, _ := value.(string)
+		if v == "" {
+			return nil // nothing to check
+		}
+
+		var foundId string
+
+		err := db.
+			Select("id").
+			From(tableName).
+			Where(dbx.HashExp{"id": v}).
+			Limit(1).
+			Row(&foundId)
+
+		if (err != nil && !errors.Is(err, sql.ErrNoRows)) || foundId != "" {
+			return validation.NewError("validation_invalid_or_existing_id", "The model id is invalid or already exists.")
+		}
+
+		return nil
+	}
+}
+
+// NormalizeUniqueIndexError attempts to convert a
+// "unique constraint failed" error into a validation.Errors.
+//
+// The provided err is returned as it is without changes if:
+// - err is nil
+// - err is already validation.Errors
+// - err is not "unique constraint failed" error
+func NormalizeUniqueIndexError(err error, tableOrAlias string, fieldNames []string) error {
+	if err == nil {
+		return err
+	}
+
+	if _, ok := err.(validation.Errors); ok {
+		return err
+	}
+
+	msg := strings.ToLower(err.Error())
+
+	// check for unique constraint failure
+	if strings.Contains(msg, "unique constraint failed") {
+		// note: extra space to unify multi-columns lookup
+		msg = strings.ReplaceAll(strings.TrimSpace(msg), ",", " ") + " "
+
+		normalizedErrs := validation.Errors{}
+
+		for _, name := range fieldNames {
+			// note: extra spaces to exclude table name with suffix matching the current one
+			// 		 OR other fields starting with the current field name
+			if strings.Contains(msg, strings.ToLower(" "+tableOrAlias+"."+name+" ")) {
+				normalizedErrs[name] = validation.NewError("validation_not_unique", "Value must be unique")
+			}
+		}
+
+		if len(normalizedErrs) > 0 {
+			return normalizedErrs
+		}
+	}
+
+	return err
+}