Incorrect behavior using html/template with AddAlternativeWriter

[BorisKoz]

There is an issue where if the template crashes, the gomail.Send(sender, msg) returns the error, therefore implying correct error handling, but the email is sent regardless of template execution. I.e.: the html contains:

a class="button-3" href="{{.Data.ConfirmationLink}}"> Confirm Email

where Data is a map. the template is configured for "missingkey=error", so if Data does not contain this key, the function tmp.execute(w, mail) will return an error. However, the email will still be sent:

As seen, with the error log being:

{"level":"error","time":"2022-12-27T13:47:24+03:00","message":"Could not send email to \"xxx\": gomail: could not send email 1: template: emailConfirmation.html:110:53: executing \"emailConfirmation.html\" at <.Data.ConfirmationLink>: map has no entry for key \"ConfirmationLink\""}

I might be wrong in pointing this out, but in my opinion, if an error is found while executing the message template writer, the whole message should be discarded

[BorisKoz]

I should add, that executing the template beforehand is an option, and it certainly helps, but it means wasting memory and performance - you need an extra buffer for the mail and an extra execution time

[wneessen]

This module isn't maintained anymore. It might be worth looking at go-mail which is actively maintained and supports text.Template/html.Template out of the box. The syntax is very similar, so a switch should be faily simple.

[BorisKoz]

This module isn't maintained anymore. It might be worth looking at go-mail which is actively maintained and supports text.Template/html.Template out of the box. The syntax is very similar, so a switch should be faily simple.

Thank you! managed to switch in a blink of an eye. The only thing is - got some problems with SMTPAuthLogin there. maybe would open a request later, not a pressing issue - plain works!