Server-side Validation
As the client can not be trusted to validate all the data correctly, there will be server-side checks for the validity of the received value(s).
If such a validation fails, the form is sent back to the client with additional validation error information.
Structure
Each element that can hold a validator
property can also have a validation_error
property.
Additionally the choice
element can have a validation_error
in the allow_selected
property.
The validation_error
property is an object holding the rule name as a key (e.g. min_length
).
The value corresponding to the key is a boolean which indicates whether or not the validation rule has been broken.
Most of the time unbroken validation rules will not be present in the validation_error
object.
{
"type": ?boolean,
"min_length": ?boolean,
"max_length": ?boolean,
"required": ?boolean,
"min_value": ?boolean,
"max_value": ?boolean,
"numeric": ?boolean,
"letters_uppercase": ?boolean,
"letters_lowercase": ?boolean,
"symbols": ?boolean,
"char_blacklist": ?boolean,
"pattern": ?boolean,
"allow_selected_min": ?boolean,
"allow_selected_max": ?boolean,
"option_disabled": ?boolean,
"valid_options": ?boolean
}
The type
Validation Error
If the type
attribute is set to true, the result value sent to the server did not match the format that was expected (e.g. the server expected an array<number>
but received a string
instead).
Handling Validation Errors
It is recommended to show a suitable error message if a validation rule has been broken.
Notable Cases
The max_value
& min_value
Errors
The max_value
and min_value
errors apply for the Padlock
and the Input
element.
For the padlock
element a max_value
validation error is returned if the server finds a value inside the numbers array which is greater than (padlock.rows * padock.columns) -1
.
A min_value
validation error is returned if the server finds a value inside the numbers array which is lower than 0.
For the input
element the max_value
and/or min_value
validation error is returned if the specified max_value
and/or min_value
properties of the input
element have been disregarded.
The allow_selected_max
& allow_selected_min
Errors
The allow_selected_max
and allow_selected_min
apply for the Choice
element.
The errors will be set to true if the allow_selected.min
and/or allow_selected.max
attribute of the element have been disregarded.
Disabled Options
The option_disabled
error applies for the elements Choice
and Switchable
.
An option_disabled
validation error is returned if the server finds a selected option which is marked as disabled.
Invalid Options
The valid_options
error applies for the elements Choice
and Switchable
.
A valid_options
validation error is returned if the selected option is not one of the choosable options.
Example
Description | Example |
Single validation error
Value was empty (required) |
|
Multiple validation errors
Value was too short (min_length) Value did not match the pattern (pattern) |
|