Read file at startup Chrome extension/kiosk app

Question

I'm currently developing my first Chrome app that we'll be used as a Kiosk app later.

I'm trying to read a file at the startup of the app, that file is a config file (.json). It contains values that will be passed inside a URL once the app has launched (ie: www.google.com/key=keyValueInTheJsonFile).

I used https://developer.chrome.com/apps/fileSystem (the method "chooseEntry" especially) to be able to read a file, but in my case I would like to directly specify the path/name of the file and not ask the user to select a file. Like that I can pass the values to the redirected URL at the startup.

Any idea of how I could possibly do that?

Thanks!

Answer 1

If your file is in the package you can read it using simple XHR or Fetch. You can't use web filesystem since it has different purpose and Chrome filesystem (user's FS) won't work here either since it needs a user interaction.

Use function getURL to get a full URL to the resource and then make XHR call:

var rUrl = chrome.runtime.getURL('file.json');
fetch(rUrl).then((response) => {
  return response.json();
})
.then((fileContent) => {
  // the content
})
.catch((cause) => console.log(cause));