Javamail and the Google API

[Neil Barton]

I want to send emails from my Java app. I can send them from my own domain using the JavaX-mail library but I want to send them so that they come from my GMail account. I have looked at the Google documentation regarding OAuth2 authentication and tried to follow it without success, it seems disjointed and doesn't have a clear step-by-step tutorial. Has anyone created one? Are there any straight forward tutorials?

[Tim Holloway]

It's not as easy as it used to be since Google added extra constraints on clients. I had to set up some IPV6 stuff in my DNS, for one.

I have a client set up to address port 465 at smtp.gmail.com using TLS.  That used to be enough, but as I said, I've had to adjust things since Google tightened up authentication and I haven't checked to see if I've got it all working. Login was via userid/password over TLS, not OAUTH, though.

[Neil Barton]

Thanks Tim, no I use that system for everything else but it no longer works with GMail :-(

[Tim Moores]

Do you need or want to use OAuth2? If not, https://www.google.com/settings/security/lesssecureapps may be an option.

[Neil Barton]

Thanks Tim, unfortunately less secure apps has been deprecated and I can't use it any more. OAuth2 seems to be the only option. It is incredibly complicated though and I cannot find a simple straight forward, up to date, guide. The guides either refer to things that don't exist any more or simply get so complicated I end up going in cricles!

[Tim Holloway]

I find it unlikely that OAUTH2 is the only option, as its protocols aren't likely to play well with automated setups.

However to make up for the "less secure apps" deprecation, you might need to ensure that your DNS can vouch for you to google, as I mentioned earlier (having to add some IPV6 stuff to my DNS).

Check this out. It may help:

https://www.gmass.co/blog/gmail-smtp/

[Neil Barton]

You're right, OAuth2 is basically unusable (at least by me!). I followed your link and got to the point where it says find "App passwords" in my Google A/c. It's not their. There is the similar "Your connections to 3rd Party Apps" but it doesn't help as I can't seem to add a new one!
Google makes this really difficult!

[Neil Barton]

Oh wow! Wait! I searched for google app password and it came up with the app passwords screen. I set it up and guess what, it worked! Whoopee! Thanks Tim!

[David Garratt]

I'm glad it's not just me who has been facing this problem. I write java applications which run as a service using a wrapper. They have not user interface, web component etc but do need to send emails. Recently Microsoft Hotmail/Outlook deprecated SMTP and I was looking at OAUTH2 but decided instead to send emails using my Apple account. I got the impression that apart from being inherently complicated to code, it also seems like it's not consistent, with Microsoft doing it slightly different than google and urrrggggggh - what a mess.

I was wondering if someone could write a program which could accept SMTP emails from a client but forward them on using AUTH2 authentication - like a proxy to help out legacy apps.

Dave