How to read all emails in gmail using google apps script - google-apps-script

Question

I'm trying to read ALL email in my gmail account - inbox, sent, draft, trash, emails with labels, archive, etc. I could live without the junk but I want everything else.
(all examples below use try {} catch {} to avoid errors with empty labels etc.)
I've tried
for (var i=StartLabel; i<=EndLabel; i++)
{
var label = labels[i].getName();
// get all messages, then join them into a single dimension array
var messages = GmailApp.getMessagesForThreads(GmailApp.search("label:" + label))
.reduce(function(a, b) {return a.concat(b);});
CountByLabels += messages.length;
}
That gives me everything in the labels (I think) but not the other stuff.
I tried other things, to get the inbox (to combine with the above) or all of the emails
var messages = GmailApp.getMessagesForThreads(GmailApp.getInboxThreads()).reduce(function(a, b) {return a.concat(b);});
CountInbox += messages.length;
but I only get about 549 results (GMail shows 5,478). If I add in the results from getPriorityInboxThreads I get 1,829 results.
I tried
// get all messages, then join them into a single dimension array
var messages = GmailApp.getMessagesForThreads(GmailApp.search("(is:unread OR is:read) in:anywhere")).reduce(function(a, b) {return a.concat(b);});
CountByLabels += messages.length;
I get 598 results.
I tried different search terms in the code directly above, eg:
is:unread = 528 results
is:read = 1,037 results
is:read OR is:unread = 599 results
None of them gave the right number, or even close, and incidentally if I try those search terms directly in gmail I get a totally different, and much higher, result for each - several thousand, or 'many'.
I don't think this is related to How to use Google App Scripts to retrieve Gmail emails in a customised way? as the numbers returned are not round numbers (eg 500).
I'm assuming that I can use getSpamThreads, getStarredThreads, getTrashThreads, getDraftMessages to get the relevant folders but until I understand why I'm only getting some emails from the inbox I don't trust those to give me everything.
Can anyone help?

Answer 1

Try this:
function allEmailsInLabels() {
var allLabels,i,j,L,L2,msgCount,theCount,threads,thisLabel;
msgCount = 0;
theCount = 0;
allLabels = GmailApp.getUserLabels();
L = allLabels.length;
for (i = 0; i < L; i++) {
Logger.log("label: " + allLabels[i].getName());
thisLabel = allLabels[i];
threads = thisLabel.getThreads();
//Logger.log('threads: ' + threads);
L2 = threads.length;
for (j = 0; j < L2; j++) {
msgCount = threads[j].getMessageCount();
//Logger.log('thread message count: ' + threads[j].getMessageCount());
// You could do something with threads[j] here like
// threads[j].moveToTrash();
theCount = theCount + msgCount;
};
};
//Logger.log('theCount: ' + theCount);
};
It first gets all the labels, then the threads, then the message count in each thread, and keeps a running count. You'll also need to get the messages in the inbox, that code doesn't include them. This is the sample code from the documentation that shows the basic concept:
// Log the subject lines of your Inbox
var threads = GmailApp.getInboxThreads();
for (var i = 0; i < threads.length; i++) {
Logger.log(threads[i].getFirstMessageSubject());
}

Answer 2

I had the same question. Reading a little bit more in the reference in the Google Developers Website, I discovered, reading about the function moveToInbox, a Google sample that used the Search to get all e-mails that weren't in the Inbox (https://developers.google.com/apps-script/reference/gmail/gmail-thread#movetoinbox). I decided to combine this with the getInboxThreads and with these two, my code was shorter and found every e-mail that I had received (less spam and junk).
function getEmails() {
var generalThreads, inboxThreads;
inboxThreads = GmailApp.getInboxThreads();
generalThreads = GmailApp.search('-in:inbox');
}
Every single email that was in the folder "All mail" in the Gmail was in these two variables after this.
I don't know if this can help anyone, but surely helped me.

Answer 3

I know this is coming a bit delayed, but having had the same problem and looking at some of the solutions offered here, I wanted to offer up my own solution, which also uses the search function:
function getEmails() {
var allEmailThreads = GmailApp.search('label:all')
}
This actually filters for every email, regardless of the mailbox, and seems to me to be the simplest solution to the question.

Answer 4

This is not an answer to your problem (but is probably one of the reasons your total results returned don't agree with what you are seeing in gmail inbox) but highlights one of the problems I encountered when calling getPriorityInboxThreads() is that it ignores any thread that is not flagged as "important" in the primary inbox.
//returns 10 threads and 1st message for each thread
function getThreads(){
var ret = '';
var threads = GmailApp.getPriorityInboxThreads(0, 10);
for (var i = 0 ; i < threads.length; i++) {
var id = threads[i].getId();
var message = GmailApp.getMessageById(id);
ret += "subject: " + message.getSubject() +'\n';
Logger.log("subject: " + message.getSubject());
/*Edited this out as it doesn't return anything
//check for labels on this thread
var labels = threads[i].getLabels();
for (var j = 0; j < labels.length; j++) {
Logger.log(labels[j].getName());
} */
}
return ret;
}
"Important" is classed as a system flag and getPriorityInboxThreads() ignores any thread that is not flagged important....
I would like to select all threads in "Primary" inbox irrespective of being labelled as "important".
To test, simply change any thread in inbox to important or not etc.

Answer 5

After I published a video on how to get Gmail messages into a Google spreadsheet, I received a feedback from some viewers that they could only get a number of messages but others fail to be processed. Therefore, I did some research and found that the process of getting emails may fail and make the system unable to handle the huge amount of emails. This is mentioned in the Gmail API here:
https://developers.google.com/apps-script/reference/gmail/gmail-label#getthreads
The documentation suggests to use getThreads(start, max) where start and max are the limiting parameters.
You may view the video and download the full code from YouTube and GitHub:
https://youtu.be/gdgCVqtcIw4