# Creating and attaching script validators ## Creating a validator A script validator is one of the artifact types in the repository. To add a script validator, go to the tab **Library → Script validators**, and then click the button on the right side **Add a script validator.**

## Edit window The edit window in the repository allows you to change the validator content and the returned keys and default error messages. In the section **Parameters** all input and output validator keys resulting from the code content should be added (error keys). The parameters window can be displayed by clicking the button in the left panel ![](https://2112972046-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F2CssJT0zIo4SJQLbSZ6l%2Fuploads%2FlcsQX63BJLjsjRv1no0n%2Fimage.png?alt=media\&token=3d1b4f04-bad2-4656-b0d6-1520fc814dcf). More information about the editor itself can be found in the [Script validator editor](https://docs.eximee.com/documentation/documentation-en/budowanie-aplikacji/logika-biznesowa/scriptcode/walidatory-skryptowe-validationscript/edytor-walidatorow-skryptowych).

**Figure 2.** Script validator edit window

## Attaching to the application Attaching a script validator to an application does not differ from attaching a standard validator. For a specific component in the panel **Properties** you should select **Data quality → Validators → Add validator**, and then search for its name. In the tab **Input parameters** you should select the appropriate component in the field **Select component or constant**.\ The switch in the column ***Call when empty*** is responsible for invoking the validator even when there is no value in the indicated field (e.g. when a value is removed from a text field).

**Figure 3.** Attaching a script validator to the application

## Creating a validator error message The content of the error message (key translation) of the script validator must be defined in the component/application after attaching the validator. Adding the message content in the script is not an error, but it will not be visible in the edit window of the component/application. After attaching the validator, both the key and its translation will display the key name defined in the content of the script validator:

**Figure 4.** Translation of the script validator key

\ You should edit the translation column and enter the message text that should appear when the validator returns a specific error message key. If it is necessary to use variables in the error message, these variables should be listed in the code as parameters (parameters: \[value1, value2, etc.]), and then referenced in the error message in the component/application as follows: {0} for the first parameter, {1} for the second parameter, {2} for the third, etc. ``` let minimumAge = 18; let maximumAge = 25; if (minimumAge > ageDifference || maximumAge < ageDifference) { return [{ 'key': 'en.LCL_birthDate.outOfRange', 'parameters': [minimumAge, maximumAge, 'This application can be submitted by people aged {0}-{1}.'] }]; ```