Google Script Email loop - email

Question

I am relatively new to programming, and have recently been working on a script to send emails from a google spreadsheet when a cell in a certain column is changed. The recipient is assigned based off of an email address in another column in the same row as the change. I am having difficulty getting my code to stop running after the first email. As it is, the script runs indefinitely (at least until I run out of emails for the day).
Here is the code:
function sendNotification() {
var sheet = SpreadsheetApp.getActiveSheet();
//Get Active cell
var mycell = sheet.getActiveSelection();
var cellcol = mycell.getColumn();
var cellrow = mycell.getRow();
var address = sheet.getRange("C" + cellrow).getValue();
var streetAddress = sheet.getRange("F" + cellrow).getValue();
var startRow = 2;
var numRows = 2000;
// Fetch the range of cells A2:O2000
var dataRange = sheet.getRange(startRow, 1, numRows, 15)
// Fetch values for each row in the Range.
var data = dataRange.getValues();
for (i in data) {
var row = data[i];
var emailAddress = address; // First column
var message = streetAddress +" Has been Submitted for permitting!"; // Second column
var subject = "The above Address has been Submitted For Permitting! We will Follow up with you when it has been approved.";
//Check to see if column is H to trigger
if (cellcol == 8 && sheet.getName() == "Sheet1" && mycell !== "")
{
//Send the Email
MailApp.sendEmail(emailAddress, message, subject);
}
//End sendNotification
}
}
What can I do to resolve this? Would a loop be the best option? How would I implement this?
How about this approach?
var EMAIL_SENT = "EMAIL_SENT";
function onEdit(e) {
var ss = SpreadsheetApp.getActiveSpreadsheet();
var sheet = ss.getActiveSheet();
var mycell = e.range;
var cellcol = mycell.getColumn();
var cellrow = mycell.getRow();
var emailAddress = sheet.getRange("C" + cellrow).getValue();
var streetAddress = sheet.getRange("F" + cellrow).getValue();
var subject = "The above Address has been Submitted For Permitting! We will follow up with you when it has been approved."
// Fetch values for each row in the Range
var message = streetAddress +" Has been Submitted for permitting!";
var emailSent = sheet.getRange("O" + cellrow).getValue();
if ( cellcol == 8 && sheet.getName() == "Sheet1" && emailSent != EMAIL_SENT) { // Prevents sending duplicates
MailApp.sendEmail(emailAddress, subject, message);
sheet.getRange(cellrow, 15).setValue(EMAIL_SENT);
// Make sure the cell is updated right away in case the script is interrupted
SpreadsheetApp.flush();
}
}

Answer 1

If you use the onEdit() the function will be triggered every time you edit the cell. Is this what you want?
What I assume you're looking for is a script that:
Reads every row of the active sheet
If the 8th column is not empty, sends an e-mail to the address in the first column
The whole script is trigger upon the user requests (not when the user edits a cell)
In this case the first approach is better, the sendNotification(). Also a loop is necessary to read all the rows. And the IF statement should be something like if (row[8] != "") then send the e-mail.
In this case row which was defined as row = data[i] in your first script will have the values of all the cells in the row being read in the loop. So row[8] will have the value of the 8th (column H), which you want to check for emptiness, thus if(row[8] != "").
Also, if I understand correctly the e-mail adress should be emailAddress = row[1] inside the loop, because the email address is different every row.

Answer 2

Your second approach var EMAIL_SENT = "EMAIL_SENT"; is almost similar to the simple extension of the code that sets the cells in a column to 'EMAIL_SENT' for each row after sendEmail is called given in Section 2: Improvements. Within tutorial, each cell was marked in each row every time an email is sent. With that, you should mark edited cells as unsent then you will be able to re-run the script later on, avoid sending email duplicates and will only send the edited cells.
To make your code more efficient and help you improve the performance of your scripts, there are also list of best practices given.