Sending a test e-mail results in error.

Not so quick ;-) The 4.0.x is WIP and certainly not functional. Will let you know when it's ready for tests later today.

This should now be resolved. The re-factoring has now been completed as soon as 📌 Configuration - "Test Email" tab not functional, throws error. Fixed will have been merged.

Please not though, that I have replaced the fully undocumented and most likely unmaintained library file with the official API library from ElasticEmail which will be installed with composer automatically, see 📌 Replace API client with composer package Fixed . The only downside: they don't seem to be supporting the from name or the reply to name. If we still want to have that, we would have to raise an issue upstream in the library which is maintained at https://github.com/ElasticEmail/elasticemail-php

The only downside: they don't seem to be supporting the from name or the reply to name.

Ok, lets continue without it.

This should now be resolved.

I'm still getting the NULL error with the latest dev.

Swap the NULL to empty string '' in ElasticEmailSendTest.php#L163

and this will fix the issue. However, it will lead to another error, but since this "Email Test" feature is WIP, I will let you finish refactoring the code first.

I have now removed all "from name" and "reply to name" instances as we currently don't support them. We can re-introduce them later properly when we get to work on ✨ Add ability to customize the e-mail's From Name Postponed .

When I click the submit button (to send the test e-mail), now I am getting:

InvalidArgumentException: Invalid value for enum '\ElasticEmail\Model\BodyContentType', must be one of: 'HTML', 'PlainText', 'AMP', 'CSS' in ElasticEmail\ObjectSerializer::sanitizeForSerialization() (line 98 of /app/vendor/elasticemail/elasticemail-php/lib/ObjectSerializer.php).

Ah, I was wondering about that. I used the values just like in emails, i.e. text/html or text/plain. Was looking for documentation at their end but couldn't find one. But with that error message, I was able to correct that now.

Now I am getting

Error: Call to a member function addError() on null in Drupal\elastic_email\Plugin\Mail\ElasticEmailMailSystem->elasticEmailSend() (line 218 of modules/contrib/elastic_email/src/Plugin/Mail/ElasticEmailMailSystem.php).

I just created a dummy account. If it worked correctly, I should be getting a Drupal message saying that I am not allowed to send from that domain (or something along those lines).

Feel free to use my dummy creds:
nosssweat2016@gmail.com
EAF003414250AA789448DE0DC4963AACCBBD68809BCC30A5C87F747C5DB23AB78781FDC2A2FC2336D5D96F639ED86DD4

Sorry for all those issues. Fixed that one now too. And thanks for the credentials, I'll go and test everything with them later today too.

OK, sending email is now possible with the latest commit.

Account information and statistics still can't be collected, and I've opened an issue in their API project at https://github.com/ElasticEmail/elasticemail-php/issues/3

Let's see what they come back with.