Test for non-existing item in storage.local API

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#1

When I run this function

function loadProfiles() {
chrome.storage.local.set({advanced: data.advanced });
chrome.storage.local.get(‘advanced’, gotItem);
}

the scrit works with no problems.

When I run this

function loadProfiles() {
chrome.storage.local.get(‘advanced’, gotItem);
}

the script halts in debugger (It does not continue to run or execute the rest of the code). The item “advanced” does not exist yet and I need to find a way how to do a test if the item “advanced” exist in the database. This way as it is bug and the script will finish early.

#2

Are you saying that the get call throws an exception? Do you see anything reported in the Browser Console?

#3

Sometimes I do some mistakes in code like in the case here and in that case I don’t see any messages in console. It just stopped working. Yet I do not use exceptions, so maybe I could use try … catch … to prevent console to stopped working? I did not tried yet. I forgot I could do it.

I have found a way how to test non-existing item in storage…

function checkIfExists(item) {
  if (chrome.runtime.lastError) {
    console.log("error:" + chrome.runtime.lastError);
    console.log(chrome.runtime.lastError);
  } else {
    if ( ! ( "initiated" in item ) )
      console.log("Not initiated");

    if ( ! ( "advanced" in item ) )
      {
      /* Insert new data object */
      chrome.storage.local.set(data, () => { 
        if (chrome.runtime.lastError) { console.log("local.set Error: " + chrome.runtime.lastError); } 
        chrome.storage.local.set( {initiated:true} );
        } );
      }
      else
        loadData()
  }
}