Applies to Pega Platform 7.2-8.5

Specifying validations

Client-side validation

Server-side validation

Registering a custom validation

Important files for debugging validation errors

Common problems

Specifying validations

Validation is a process of testing and ensuring that the user has entered required and properly formatted information through the web form. Validation rules not only ensure that incoming data is valid, but they also provide an additional layer of security. You can configure validation to occur either client side (if the data is being entered by a user) or server side (if the data is coming from an external system).

Client-side validation

Client-side validation occurs as a user is entering data into a browser. If a user enters data that is invalid or outside acceptable ranges, an error is raised that can be acted upon before the data enters the system. 

In client-side validation, all the input validations and the error recovery process are carried out on the user’s browser. The browser performs the validation. 

Client-side validation is triggered based on the event attached to validationtype.

Default validations that come with each control are as follows:

• Boolean, true-false
• Currency, decimal
• Date and Time, datetime
• Date, date 
• Decimal, decimal
• Email, validemailaddress
• Integer, integer
• Percentage, decimal
• Phone, validphonenumber
• Time, timeofday
• URL, pxisvalidurl

Server-side validation

Server-side validation occurs when data has entered the system from any external source and cannot be validated beforehand. In this case, when invalid data is detected by a validation rule, an error is raised that marks the data as invalid. This can be detected and acted upon by other rule types to correct or notify someone about the error.

In server-side validation, all the input validations and error recovery process are carried out on the server side. The browser sends the request to the server to perform validations.

• Edit validate rules (Rule-Edit-Validate) handle Java code testing to check the validity of the input. Edit validate is associated to a particular property and validate value of the property on clipboard, if validation fails, Any commit of flow of execution does not forward. Some out-of-the-box controls might have equivalent client-side validation logic implemented, for example, email. Java code might be dependent on third-party libraries. Always try to run Java code separately to detect and resolve any ambiguity that might exist.
• Validate rules (Rule-Obj-Validate) evaluate general logical expressions. Validate rule is associated to an action (Flow action) and validates the assignment to be submitted. Functions used in building validate rules are evaluated at runtime. Evaluation is context-sensitive. Evaluation of the logical expression is triggered on Submit of a property value and stops processing if validation fails.
• Constraint validation rules for Declarative expressions (Rule-Declare-Constraints) run every time a property referenced in the constraint is changed. If a property in the clipboard fails the constraint, then an error message is added on the property. Because evaluation is performed every time a property changes, this might cause performance issues.

Registering a custom validation

1. Create an instance of validation type.

var numeric_decimal = new validation_ValidationType("decimal", numeric_isDecimal);

2. Add event listeners.

numeric_decimal.addEventFunction("onchange", numeric_isDecimal);
numeric_decimal.addEventFunction("onblur", numeric_isDecimal);

3. Add implementation logic.

function numeric_isDecimal(){

//Logic goes here

}

4. Add the implementation logic in an HTML fragment or a JS file and then add this to the harness scripts.

Important files for debugging validation errors

The pega_validators.js file contains validation logic for each validator registered.

The cs_valid.js file reads through every input field in the DOM, reads the validation type attribute, and invokes the actual validation logic that is present in the pega_validators file.

Standard client-side validation scripts are in the text file rule named webwb.CSValid.js. To allow for localization, the corresponding error messages are in the HTML fragment rule named CSValid. You can add custom client-side validation scripts or error messages application-wide by overriding the HTML fragment rule named UserWorkForm, which is included in the fragment WorkFormStandard, which in turn is included in the HTML code for every user form.

Common problems

The following table lists the commonly reported problems and how to prevent them:

Related Content

About Validate rules

Validating field values on a form