Got 401 response when calling my own Google Apps Script - google-apps-script

Question

I wrote a test web app using apps script. I deployed it to execute as "User accessing the web app" and set access to "Anyone who has a Google account". I then tried to call the web app function from another script which acts as the client. I did all of this while logged into my google account, both web app and client are in the same browser window (in different tabs). But I always get a 401 error. I then tried adding some oauthScopes to the appsscript.json file for the client script, but this didn't help. Any help solving this would be appreciated.
Web app code:
function doPost(e) {
if(typeof e !== 'undefined') {
let par = e.parameter;
let retval = par.x*3;
let retobj = {"retval":retval};
return ContentService.createTextOutput(JSON.stringify(retobj));
}
}
Client code:
function callWebApp(x) {
Logger.log("starting call webapp");
var payload = {
"info" : "some text",
"x" : 3,
"type" : "post",
};
var options = {
"method" : "POST",
"payload" : payload,
"followRedirects" : true,
"muteHttpExceptions": true
};
var result = UrlFetchApp.fetch(urlString, options);
Logger.log(result.getResponseCode());
if (result.getResponseCode() == 200) {
Logger.log('got response');
var params = JSON.parse(result.getContentText());
Logger.log(params.retval);
}
return 1;
}
appscript.json for client:
{
"timeZone": "America/New_York",
"dependencies": {
},
"exceptionLogging": "STACKDRIVER",
"runtimeVersion": "V8",
"oauthScopes": [
"https://www.googleapis.com/auth/script.deployments",
"https://www.googleapis.com/auth/script.deployments.readonly",
"https://www.googleapis.com/auth/script.external_request",
"https://www.googleapis.com/auth/script.projects",
"https://www.googleapis.com/auth/script.processes",
"https://www.googleapis.com/auth/script.projects.readonly"
]
}
Execution log:
7:47:30 PM Notice Execution started
7:47:30 PM Info starting call webapp
7:47:30 PM Info 401.0
7:47:30 PM Notice Execution completed

Answer 1

Modification points:
When you deployed the Web Apps as Execute as: User accessing the web app and Who has access: Anyone with Google account and you want to access to the Web Apps using the script (in this case, it's Google Apps Script.), it is required to request to the Web Apps by including the access token in the request header.
And, when the access token is used for requesting to the Web Apps, please include the scope of https://www.googleapis.com/auth/drive.readonly and/or https://www.googleapis.com/auth/drive to your current scopes in your client.
In your script, it seems that urlString is not declared. Although I'm not sure whether this might be declared elsewhere, please confirm it again.
When these points are reflected to your script, it becomes as follows.
Modified script:
From:
var options = {
"method" : "POST",
"payload" : payload,
"followRedirects" : true,
"muteHttpExceptions": true
};
To:
var options = {
"method": "POST",
"payload": payload,
"muteHttpExceptions": true,
"headers": {authorization: "Bearer " + ScriptApp.getOAuthToken()}
};
Note:
If you want to make users request to your Web Apps using a script, it is also required to request to the Web Apps by including the access token in the request header. And also, it is required to share the Google Apps Script project with the user. Please be careful this.
If you cannot retrieve your expected result when above script is run, please redeploy the Web Apps as new version and test it again.
References:
Web Apps
Taking advantage of Web Apps with Google Apps Script