How to get data from google sheet to my Gmail addon - google-apps-script

Question

I tried to get some data from google sheet and display it in Gmail addons.
When i tried to run getValue() function i am getting error like below.
You do not have permission to call openById (line 29, file "Code")Dismiss
This is my code.gs file code
function createWidgetCard() {
return CardService
.newCardBuilder()
.setHeader(
CardService.newCardHeader()
.setTitle('Widget demonstration')
.setSubtitle('Check out these widgets')
.setImageStyle(CardService.ImageStyle.SQUARE)
.setImageUrl(
'https://www.example.com/images/headerImage.png'))
.addSection(
CardService.newCardSection()
.setHeader('Simple widgets') // optional
.addWidget(CardService.newTextParagraph().setText(
'These widgets are display-only. ' +
'A text paragraph can have multiple lines and ' +
getValue()))
.addWidget(CardService.newImage().setImageUrl(
'https://www.example.com/images/mapsImage.png')))
.addCardAction(CardService.newCardAction().setText('Gmail').setOpenLink(
CardService.newOpenLink().setUrl('https://mail.google.com/mail')))
.build();
}
//get data from sheet
function getValue(){
var ss = SpreadsheetApp.openById("181tnith14lu8ttAvtqsU3gHi32-UjcrPqH5Pjuenk5A");
var sheet = ss.getSheets()[0];
var lastRaw = sheet.getLastRow();
var text = sheet.getRange(lastRaw, 3.0).getValue();
Logger.log("text");
return text;
}
This is my manifest file code(appscript.json)
{
"oauthScopes": [
"https://www.googleapis.com/auth/gmail.addons.execute",
"https://www.googleapis.com/auth/gmail.readonly",
"https://www.googleapis.com/auth/script.storage",
"https://www.googleapis.com/auth/script.external_request"
],
"gmail": {
"name": "Finetech Addon",
"logoUrl": "https://www.gstatic.com/images/icons/material/system/2x/bookmark_black_24dp.png",
"contextualTriggers": [{
"unconditional": {
},
"onTriggerFunction": "createWidgetCard"
}],
"openLinkUrlPrefixes": [
"https://mail.google.com/"
],
"primaryColor": "#4285F4",
"secondaryColor": "#4285F4",
"version": "TRUSTED_TESTER_V2"
}
}
My requirement is accessing sheet and get some data and display it on Gmail addon. It could be very helpful if anyone can provide correct code snipes.

Answer 1

I think that the scope for using Spreadsheet is required to be added to "oauthScopes" of manifests. So please add https://www.googleapis.com/auth/spreadsheets to "oauthScopes" in appsscript.json. And try again.
If this didn't work, I'm sorry.