Google will tell you your titles are too long, your GTINs are malformed and your descriptions contain HTML. It will tell you three days after you submitted, by demoting the products.
Validation rules catch all of that in your own admin, before the file ever leaves the building. The extension ships with rules for the common marketplace requirements and you can add your own.
The rules for a feed live at Catalog > Advanced Product Feeds > Feeds > Choose the feed > Content settings > Validation rules (JSON). To run and read the results, see [how to validate the feed(/how-to/validate-feed/).
Each rule specifies:
Type: the kind of check performed (e.g. required, max_length, is_one_of)
Severity: how critical the issue is (error, warning, notice, improvement)
Message: description of the problem or recommendation
Additional parameters: optional, depending on the rule type (e.g. length, values)
Each validation rule defines how the module checks a specific field’s value.
You can combine multiple rules per field (for example: required + max_length).
The table below lists all available rule types, their descriptions, and any additional parameters required.
Type
Description
Additional Field(s)
required
Checks that the field exists and is not empty.
-
max_length
Ensures that the field value does not exceed the specified length.
length - maximum allowed characters
min_length
Ensures that the field value is at least the specified length.
length - minimum required characters
start_with
Checks that the field value begins with one of the allowed prefixes.
values - array of allowed prefixes (e.g. ["https://", "http://"])
end_with
Checks that the field value ends with one of the allowed suffixes.
values - array of allowed endings (e.g. ["kg", "g", "lb"])
is_one_of
Validates that the field value matches one of the allowed values.
values - array of permitted values
alphanumeric
Ensures that the field contains only alphanumeric characters.
-
ascii
Ensures that the field contains only ASCII characters.
-
unicode
Validates that the field contains valid Unicode characters.
-
numeric
Ensures that the field contains only numeric values.
-
without_html
Checks that the field does not include HTML tags.
-
How rule parameters are defined
If a rule requires extra parameters, they are declared inside the module’s PHP validator class as constants: