Press "Enter" to skip to content

What are the validation rules in Pega?

12

Introduction

In this post, we will see about different types of validation rules available in Pega.

Every application needs correct data to process any request.

Imagine you are visiting an employment portal and applying for a job. When you fill any application form, you may come across different fields with different validation. For example, in an email address field, if you don’t use ‘@’ and ‘.com’ you may get an error as “Enter valid email”.

The same way Pega application may use different forms to get input from the user. As a developer, we need to make sure the data provided by the user are valid. We use different validation rules to perform this task.

What are the types of Validation?

  1. Server side validation – Implemented by java code. Involves a server trip for validation.
  2. Client side validation – Implemented by javascript code. Validation happens in the browser.

We will see about these types in a separate lesson.

What are the different Validation rules in Pega?

      1. Validate rule.
      2. Edit Validate rule.
      3. Edit input rule – formatting input.
      4. Constraints rule.
      5. Validation through Property definition and Control.
      6. Custom javascript validation.

1) What is a Validate rule?

  • Ensures that a valid data is entered in form or validates data received from other system.
  • When a field fails validation, the rule adds an error message and prevents successful submission of form.
  • We can add validation for any property rule and we can customize the error message.
  • Mostly used in Flow actions and Activity rules.

How to configure a Validate rule?

  • It is a server side validation. Mostly we will use in a flow action rule to validate the fields in form.
  • It is part of process category.

There are 2 important tabs to configure in a Validate rule:

  1. Validate
  2. Input

Validate tab

Property – Enter a property. It can be single value or a page/pagelist.

Additional validation – We can refer another Validate rule.

Conditions – On clicking add, we get a popup to configure the conditions to validate.

1. For single value property validation,

In the popup, we can configure many criteria.

Required – Expects the field to be mandatory and throws error message as “This field may not be blank”, if empty.

Enable conditions – True / False – Enables or disables the below conditions.

Add a function – Select all the required functions to validate the property. You can add multiple functions to validate a single property. Go through those functions.

Message – If the condition fails, then you can add a message.

Continue Validation – True / False – If a condition fails, then you can stop the validation right at the moment by un-checking continue validation.

2.  For aggregate property,

You need to use a validate rule to run on each page.

Input tab

There are 5 types of input values:

  1. None – scenario explained above.
  2. Input property.

Imagine a scenario where we have different validation conditions for male and female. We can handle that in single validate rule. Use input property as Gender.

Gender is a single value local list property.

Now switch to validate tab.

Add the plus icon to add different blocks of validation conditions for different input values.

Here a new block is added for Gender = Male and separate validation conditions.

3. Proposed work status

We can have special validation for cases based on work status. Imagine different validation for a case when the status is “open”. Select proposed work status in input tab. In the validate tab, you can add separate block when input value is open.

4. Flow action name – Similar to above, we can have different validation conditions for different flow actions. Mainly used in screen flow, where there is no need to create separate validation rule for separate screen.

5. Stages – Similar to above, we can have different validation conditions for different stages.

Where do we refer a Validate rule?

  1. In flow action rule validate tab. The flow action uses the validate rule to validate all the fields before successfully submitting the form.
  2. In activity using Obj-Validate method. Mainly used in validating fields while creating any case from background process or service.

2) What is an Edit Validate rule?

  • Validates an input value using java code.
  • Return Boolean value.

How to configure an edit validate rule?

  • Edit validate rules comes under Data model category.
  • Create a new edit validate rule.
  • Edit validate rules do not belong to any class.
  • Pega ships with a variety of OOTB edit validate rule. Check those before deciding to create a new one.

Edit validate rule single main tab – Java

  • Enter the Java Boolean function.
  • The code validate the automatically declared named ‘theValue’.

Validate rules don’t validate when Input value is blank.

Where do we refer an Edit validate rule?

  1. In Property rule form advanced tab.
  2. In activity using property validate method.
  3. It can also be referenced in validation rule – run edit validate conditions.

3) What is an Edit Input rule?

  • It is basically a conversion rule (not validation)  & cannot be included in validation rules.
  • Converts the data from one format to different format.
  • Uses java code for conversion.

How to configure an Edit Input rule?

  • Edit Input rule comes under Data model category.
  • Create a new edit input rule.

Imagine a scenario where you need to save the user input, only in capital letters. Use can use the below edit input to convert the format to upper case always.

Where do we refer an Edit Input rule?

  • Property rule advanced tab can refer an edit input rule.

You can test an edit input rule. Add the uppercase edit input rule to any field on rule form. After submitting the form, verify the value in clipboard. You can see the data is formatted to upper case.

Differences between edit validate and edit input rule:

  • Edit input is a conversion rule type, whereas Edit validate is a validation rule type.
  • Edit Input formats the data even though the data is invalid.
  • In a property rule, if both edit input and edit validate are specified, edit input occurs first followed by edit validate.

4) What is a constraints rule?

  • Constraints is a declarative rule, which uses forward chaining.
  • So whenever the property value is touch the validation fires by constraints rule.

How to configure a constraints rule?

  • Constraints rule comes under decision category.
  • Create a new Constraints rule.

There is a single main tab in a constraints rule – Constraints.

When – specify a when condition – this must evaluate to true.

Require that – Enter the validation function.You can use settings icon to include different functions available.

Else add message – If the ‘require that’ condition fails, then it adds a message.

Let’s look at the above example.
Here, whenever pySkillRating value changes(non–null), it should be between 1-10. Else error message will be added.

Where do we refer a Constraints rule?

  • Since it is a declarative rule, there is no need to explicitly call the rule. Pega engine takes care.

You can test a constraints rule. Use the pySkillRating property as one of the input field in a form. Enter the value as ‘100’. On submitting the form, an error message is thrown as configured in the Constraints rule.

Remember to check “Enable expression calculation” in flow action or harness form.

The feature is based on AJAX technology.

These four are the validation rules available in Pega

5. Validation through Property definition and Control.

6. Custom javascript validation.

We will discuss points 5 & 6 in ‘Server side vs Client client Validation’ (http://myknowpega.com/2017/05/13/server-side-vali…-side-validation/) post.

Hope you get the basics about validation rules 🙂

  1. Dhanu Dhanu

    Good read. You could even mention about default server side rule ‘Validate’ and why it has be overriden to do common validations. I find it useful as it automatically gets fired.

    • prem prem

      Hi Dhanu,

      See only some OOTB edit validate rules fire at the client side eg pyValidemailaddress.

      Validate rules ( rule-obj-validate) fires only at the server side means only when you submit the form.

      If I am not clear, Can you pls come up with some modified question

  2. Mahesh Mahesh

    Hi Prem,

    How to configure a Validate rule images are not being displayed in this post, could you fix it?
    Thanks for this useful information…really good stuff man.

    • prem prem

      Thanks Mahesh. Updated. Please check now 🙂

  3. pradeep pradeep

    Hi Prem ,

    I have a requirement that i want to dispaly country name w.r.t to state is if select India it has to display all states in india please help me.

    thanks in advance

  4. Sushil Sushil

    Hi Prem,
    Is there any difference b/w Property-validate and validate rule?

    • Premkumar G Premkumar G

      Hi Sushil,

      great question :).
      1. Property validate is a method; Validate is a rule.
      2. Property-validate can be used only as activity method and validate rule can be used in activity using Obj-Validate or in flowactions.
      3. Property validate depends on EditValidate rule for all the validation logic, which validate rule can make use of variety of expressions and functions.
      Validate rule is basically very easy to configure
      4. Property validate reusability is 0%. Validate rule you can reuse the rule in many flowactions and activity.

      In my assumption, Property-validate method introduced prior to Pega 6 versions and Validate rule is introduced to make the validation simple and support reusable. My suggestion, always try to make use of validate rule 🙂

      Think wisely and choose. If you need to validate 3 properties using edit validate rule then you can go for property-validate

  5. Naga Senthil Naga Senthil

    Hi prem,

    I want to validate one properties like mentioned below.

    Label field validations
    1. profession text (alphabetic,non numeric,no special charact)

    • Premkumar G Premkumar G

      Hi Nagu for your requirement, you can make use of OOTB standard edit validate ‘AlphabeticValidation’.

  6. Narasimha Narasimha

    Could you please send/update interview questions for CSA level?

    Thanks !

    • Premkumar G Premkumar G

      I’m sorry, Narasimha, right now I’m not having any interview questions at all. So sorry!

Leave a Reply

Your email address will not be published. Required fields are marked *

error: Content is protected !!