Support alternative mailing services (Mailgun, Mandrill, Sendgrid)

[ruslandoga]

Changes

This PR is similar to #2596 but hardcodes all adapters that bamboo ships with and adds some config tests.

Tests

• Automated tests have been added

Changelog

• Entry has been added to changelog

Documentation

• Docs have been updated add more mailer docs docs#351

Dark mode

• This PR does not change the UI

[bundlemon]

BundleMon

Unchanged files (7)

Status	Path	Size	Limits
✅	static/css/app.css	515.18KB	-
✅	static/js/dashboard.js	297.69KB	-
✅	static/js/app.js	12.13KB	-
✅	static/js/embed.host.js	5.58KB	-
✅	static/js/embed.content.js	5.06KB	-
✅	tracker/js/plausible.js	748B	-
✅	static/js/applyTheme.js	314B	-

No change in files bundle size

Final result: ✅

View report in BundleMon website ➡️

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Current branch size history | Target branch size history

[ruslandoga]

I couldn't find request_options in bamboo. It seems to be specific to bamboo_postmark

So I used hackney_opts in the built-in adapters.

[tenfourty]

Hi folks,
Thank you for this work, it really adds some flexibility for folks wanting to use other services to send email.

In my case I was looking at using this for Mailgun, unfortunately I don't think this will work for folks who use Mailgun's EU servers.

I had a look at the source code for the implementation, and you might need to add the base_uri for Mailgun as well. Mailgun makes a difference in the API base URL between sender domains from within the EU and outside.

You can read more about this in the Bamboo Adapter docs here.

I'll try to put a comment inline to the PR as well.

Do let me know if you want me to create a new issue for this. I felt it was important to include this as this is included in the v2 RC and it would be great to have this fix included.

Of course I might have gotten this completely wrong and if so apologies in case the MAILGUN_BASE_URI variable works (I was going off the test cases in this PR).