Seam and asynchronous email send

Over the past 3 months I've ported a JSF 1.1 business application written last year to Seam.
I'll talk of the hurdles I met, expecially porting from myfaces 1.1 to JSF RI 1.2, but now I just want to share with you my few successes.
In seam you can send an email using facelets as template engine. You can do it in same thread that displays you page, but due to high latency of smtp servers and other reasons, it's better to send it asynchronously.
My webapp is a POJO webapp, built upon spring,hibernate and seam.
All you have to do to spawn a new thread is to annotate your method with @Asynchronous, but watch out !
If your code was already working when doing it inside the display thread, now it surely will break.
WHY:
1) when seam spawns a thread, you loose the previous event/page/conversation context, so you have to put the objects you use inside the email template in a new context:

@Asynchronous
public void send(Account account) {
try {
Contexts.getConversationContext().set("account", account);
Renderer.instance().render("/email/activatedaccount.jsf");
} catch (Exception e) {
e.printStackTrace();
}

2) you loose your webapp relative paths too: if inside a display thread seam uses the ServletContext to retrieve the full path to your email template (and the resources it uses). Inside a spawned thread seam replaces the servletContext with a mockContext which resamble a ResourceBundle strategy to find resources in the classpath. So you have to move /email dir in WEB-INF/classes, togheter with the resources it uses (logo images etc..).

3) I happened to use one backing bean to process the page action, and call a send(account) method of the same class. When I marked that method @Asynchronous and debugged inside Eclipse, I saw the thread was the tomcat's one, not a new spawned one. I solved it moving the send method in another class and calling it in a new istance:


public String approve(Account account) {
...
architectMailer.send(account);
...
}

4) There's a bug (fixed in next release, perhaps already in 2.0.1 CR of tonight) about inline images not being displayed in thunderbird, but only attached. Don't go crazy, it's not your fault: wait for next release.

My 2 cents

Hope this helps