SeedCode's jason_young has created a series of blog posts that will get you up and running with the Gmail API. This approach will let you go beyond what's possible with the Send Mail script step, especially when it comes to sending attachments from server. And since the cURL options in the Insert From URL script step are supported natively across the whole FileMaker platform, the techniques used here work on the Server, Go, FileMaker Cloud and WebDirect. (This technique requires FileMaker 16 or higher since the advanced cURL options were introduced in FileMaker 16.)
Jason also built a little emoji picker, which I now can't live without. And if you haven't seen how Gmail handles resumable uploads (resuming if you lose connection), that's shown in the movie for Part 2.
The example files demonstrate how to authenticate to Gmail from within FileMaker and Jason based that on the authentication routine provided by dbservices. The wrote a great article on this where you’ll find additional info on setting up a Google project and OAuth.
Sending email using the Gmail API has let us give clients a seamless experience that they were used to in Gmail: now just some of their emails are sent from their FileMaker Server automatically. The attachments, outbox, and reply experience is what they and their customers were already used to. We hope you find this as useful as we did.
Here are the movies, example files, and instructions:
Part 3: Managing Email Threads (coming soon)
Screenshots from the example files follow: