Calling an API endpoint upon changes to any Google Sheets files - google-apps-script

Question

What I wish to achieve:
Whenever a cell is changed in any google sheet on my shared drive (by
any user on the domain) I want to call an API endpoint and include
information about which cell was edited.
My approach:
I believe Google App Scripts Add-on is what I need. Installed for all users on the domain.
I see there are "bound" scripts and standalone scripts. For standalone scripts I am not able to create any other triggers than timer and calender based triggers. Bound scripts seem to be permanently bound to a single sheet and won't impact other sheets in any way.
What am I missing?
I find a few end-to-end tutorials on blogs for making bound scripts, but nothing for generic cross-domain stuff.

Answer 1

You can achieve all this through a standalone script. Create a standalone script and follow these steps:
Step 1: Get spreadsheet ids
First you would have to get the id of the different Spreadsheets in your shared drive. You can do it in Google Apps Script itself if you use the Advanced Drive Service (see Reference below). To activate this service, go to Resources > Advanced Google services... in your script editor and enable Drive API.
Then, write a function that will return an array of the spreadsheet ids in the shared drive. You will have to call Drive.Files.list for that. It could be something along the following lines (please write your shared driveId in the corresponding line):
function getFileIds() {
var params = {
corpora: "drive",
driveId: "your-shared-drive-id", // Please change this accordingly
includeItemsFromAllDrives: true,
q: "mimeType = 'application/vnd.google-apps.spreadsheet'",
supportsAllDrives: true
}
var files = Drive.Files.list(params)["items"];
var ids = files.map(function(file) {
return file["id"];
})
return ids;
}
Step 2: Create triggers for each spreadsheet
Install an onEdit trigger programmatically for each of the spreadsheets (an edit trigger fires a function every time the corresponding spreadsheet is edited, so I assume this is the trigger you want). For this, the ids retrieved in step 1 will be used. It could be something similar to this:
function createTriggers(ids) {
ids.forEach(function(id) {
var ss = SpreadsheetApp.openById(id);
createTrigger(ss);
})
}
function createTrigger(ss) {
ScriptApp.newTrigger('sendDataOnEdit')
.forSpreadsheet(ss)
.onEdit()
.create();
}
The function createTriggers gets an array of ids as a parameter and, for each id, creates an onEdit trigger: everytime any of these spreadsheets is edited, the function sendDataOnEdit will run, and that's where you will want to call your API endpoint with information about the edited cell.
Step 3: Call API endpoint
The function sendDataOnEdit has to get data from the edited cell and send it somewhere.
function sendDataOnEdit(e) {
// Please fill this up accordingly
var range = e.range;
var value = range.getValue();
UrlFetchApp.fetch(url, params) // Please fill this up accordingly
}
First, it can get information about the cell that was edited via the event object, passed to the function as the parameter e (you can get its column, its row, its value, the sheet and the spreadsheet where it is located, etc.). For example, to retrieve the value of the cell you can do e.range.getValue(). Check the link I provide in reference to get more details on this.
Second, when you have correctly retrieved the data you want to send, you can use UrlFetchApp.fetch(url, params) to make a request to your URL. In the link I provide below, you can see the parameters you can specify here (e.g., HTTP method, payload, etc.).
Please bear in mind that you might need to grant some authorization to access the API endpoint, if this is not public. Check the OAuth reference I attach below.
(You have to edit this function accordingly to retrieve and send exactly what you want. What I wrote is an example).
Summing this up:
In order to create the triggers you should run createTriggers once (if you run it more times, it will start creating duplicates). Run for example, this function, that first gets the file ids via Drive API and then creates the corresponding triggers:
function main() {
var ids = getFileIds();
createTriggers(ids);
}
Also, it would be useful to have a function that will delete all the triggers. Run this in case you want to start from fresh and make sure you don't have duplicates:
function deleteTriggers() {
var triggers = ScriptApp.getProjectTriggers();
triggers.forEach(function(trigger) {
ScriptApp.deleteTrigger(trigger);
})
}
Reference:
Advanced Drive Service
Drive.Files.list
onEdit trigger
Install trigger programmatically
onEdit event object
UrlFetchApp.fetch(url, params)
Connecting to external APIs
OAuth2 for Apps Script
ScriptApp.deleteTrigger(trigger)
I hope this is of any help.