How to parse a simple JSON object (accessing single elements)? - json

Question

I'm trying to process simple JSON data in a Google-Apps-Script (a Webhook Receiver). For a test I send data from the console:
curl -d "{"result":true,"count":42,"exchange":"Kroakex"}" -H "Content-Type: application/json" -X POST https://script.google.com/macros/s/xxx/exec
... but I can't access the json elements in my processing function:
function doPost(e) {
var jsonString = JSON.stringify(e.postData.contents);
var jsonObj = JSON.parse(jsonString);
console.log(jsonObj); // ---> "{result:true,count:42,exchange:Kroakex}"
console.log(jsonObj.count); // ---> "undefined"
var sheet = SpreadsheetApp.getActiveSheet();
var lastRow = Math.max(sheet.getLastRow(),1);
sheet.insertRowAfter(lastRow);
sheet.getRange(lastRow + 1, 1).setValue(jsonObj['count']); // ---> nothing
sheet.getRange(lastRow + 1, 2).setValue(jsonObj['exchange']); // ---> nothing
sheet.getRange(lastRow + 1, 3).setValue(jsonObj); // ---> {result:true,count:42,exchange:Kroakex}
SpreadsheetApp.flush();
return HtmlService.createHtmlOutput("post request received");
}
When I instead create the JSON string manually with this line, it all works fine:
const jsonString = '{"result":true, "count":42, "exchange":"Kroakex"}';
Can anyone help?

Answer 1

I would like to propose the following modification.
Modification points:
I think that in your curl command, there are the modification points.
When your curl command is used, e.postData.contents is "{result:true,count:42,exchange:Kroakex}". Because at -d "{"result":true,"count":42,"exchange":"Kroakex"}", " is used in "{,,,}". In this case, your Google Apps Script cannot parse the values as JSON object. Please escape " or enclose by '. By this, e.postData.contents becomes "{\"result\":true,\"count\":42,\"exchange\":\"Kroakex\"}".
In this case, please use -L and -X POST is not required.
The modified curl command is as follows.
curl -L -d '{"result":true,"count":42,"exchange":"Kroakex"}' -H "Content-Type: application/json" https://script.google.com/macros/s/###/exec
or
curl -L -d "{\"result\":true,\"count\":42,\"exchange\":\"Kroakex\"}" -H "Content-Type: application/json" https://script.google.com/macros/s/###/exec
By above modification, your Google Apps Script becomes as follows.
Modified script:
function doPost(e) {
var jsonObj = JSON.parse(e.postData.contents); // <--- Modified
console.log(jsonObj);
console.log(jsonObj.count);
var sheet = SpreadsheetApp.getActiveSheet();
var lastRow = Math.max(sheet.getLastRow(),1);
sheet.insertRowAfter(lastRow);
sheet.getRange(lastRow + 1, 1).setValue(jsonObj['count']);
sheet.getRange(lastRow + 1, 2).setValue(jsonObj['exchange']);
sheet.getRange(lastRow + 1, 3).setValue(JSON.stringify(jsonObj)); // <--- Modified
SpreadsheetApp.flush();
return HtmlService.createHtmlOutput("post request received");
}
Note:
When you modified the script of Web Apps, please redeploy the Web Apps as new version. By this, the latest script is reflected to Web Apps. Please be careful this.
When you use the curl command, I think that the returned value might be suitable for return ContentService.createTextOutput("post request received"); instead of return HtmlService.createHtmlOutput("post request received");.
References:
Web Apps
Taking advantage of Web Apps with Google Apps Script
Added:
When you want to access to Web Apps using the URL of https://script.google.com/macros/s/###/dev, it is required to use the access token. The modified curl command is as follows.
curl -L \
-H "Authorization: Bearer ### access token ###" \
-H "Content-Type: application/json" \
-d '{"result":true,"count":42,"exchange":"Kroakex"}' \
"https://script.google.com/macros/s/#####/dev"
In this case, https://www.googleapis.com/auth/drive.readonly and https://www.googleapis.com/auth/drive can be used for the scope.
Reference:
How to use dev mode from outside