Cannot interpolate custom functions parameters

[masciugo]

Are you requesting a feature, reporting a bug or asking a question?

feature

What is the current behavior?

I have an async custom function called getRemoteObjectProp that return a remote object property. So the function run an http request to fetch the remote object and than provide the specified prop. The first parameter is the request url. I would like to build it dynamically:

{
  "name": "id",
   "type": "text"
},
{
  "name": "q1",
  "type": "expression",
  "expression": "getRemoteObjectProp('/misc/AIFAdrugs/{id}', 'ATCcode')")
}

My workaround at moment is replacing the placeholder $ with the last parameters in an orderly manner

{
  "name": "q1",
  "type": "expression",
  "expression": "getRemoteObjectProp('/misc/AIFAdrugs/$', 'ATCcode', {id})")
}

What is the expected behavior?

I'd like an interpolation like the one you can use in the choicesByUrl url property

thank you

[masciugo]

.. or maybe having a function that interpolate a string like:

"expression": "getRemoteObjectProp(interpolateFunction('/misc/AIFAdrugs/{id}'), 'ATCcode')")

.. but I don't know if nested functions work

[masciugo]

I am trying my custom interpolation solution to have my desired expressiongetRemoteObjectProp('/misc/AIFAdrugs/{id}', 'ATCcode')) working:

const getRemoteObjectProp = function(args) {
  let url = args[0],
    prop = args[1]

  if (url && prop) { // all params must be well defined

    url.match(/\{[A-Za-z0-9_\-.]+\}/g).every( ph => {
      let name = ph.slice(1,-1),
        value = this.survey.getVariable(name) || this.survey.getCalculatedValueByName(name) || this.survey.getQuestionByName(name)?.value  

      if (value) {
        url = url.replaceAll(ph,value)
        return true
      } else {
        url = undefined
        return false
      }

    })

  } else {
    url = undefined
  }

  if (url) {
    if (url.startsWith("/")) {
      url = window.location.origin + url
    }
    url = new URL(url)
  }

  [...]

but this work only for not nested questions. If I try to use it in a paneldynamic (for example)this.survey.getQuestionByName(name)?.value of course would not work. How can I reach all question values defined here

thanks a lot

[andrewtelnov]

@masciugo You can check for this.row context if you are running expression inside the matrix and I have just added this.panel context for panel dynamic. Here is the PR.
Your code will be:

const context = !!this.row ? this.row ? (!!this.panel ? this.panel : this.survey);
const q = context.getQuestionByName(questionName);
if(!q && context !== this.survey) q = this.survey.getQuestionByName(questionName);

Regarding a new functionality, there is a high possibility that some developers requrie to pass "{val}" to a server.

Thank you,
Andrew