Retrieve field values outside of Questions

[iguannago]

There is a need to access an answer from a previous step from a Page type. Currently, this is possible from a Question type. Unfortunately, it is not possible from Page, ExitPoint, etc.

The below is a workaround provided by @michaeldfallen to achieve this. However, it requires being running the 2.0.0-1 version.

const { form, textField } = require('@hmcts/one-per-page/forms');
const { Page } = require('@hmcts/one-per-page');
const paths = require('paths');

class FormDownload extends Page {

    get url() {
        return paths.formDownload;
    }

    get benefitType() {
       const fields = form(textField.ref(this.journey.BenefitType, 'benefitType')).bind(this).retrieve(this.req);
       console.log(`benefitType: ${fields.fields[0].value}`);
   }

}

module.exports = FormDownload;

Therefore, for the time being, we will meet this requirement by extending from the Question type and later on once we upgrade to the 2.0.0-1 version we will refactor this work to extend from the Page type and use the code provided by Michael here. He suggested providing a cleaner way to do it as well.

I use this issue ticket to make a note of this work and discussion between him and me.

[michaeldfallen]

We could do this by adding a retrieveValue function on the journey, so that a developer can declare:

const benefitType = this.journey.retrieveValue(textField.ref(this.journey.BenefitType, 'benefitType'));

The retrieveValue function would need to replicate the retrieve function of the Form class.

[michaeldfallen]

The retrieveValue function should either enforce session (and so the developer should use the requireSession middleware on the step they are building) or should have a mechanism for handling the user not having a session.

Perhaps returning an Optional makes sense here?