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by moozeek 5243 days ago
All this is nice and well, but how would one build an "unsubscribe" link into a newsletter system without a GET request changing the state of the resource (i.e. deleting the email address from the active recipients table by just clicking a link)?

Would this be the exception to the rule or is this problem totally unrelated to REST?

BTW: I'm not debating, I really wanna know.
3 comments
solutionyogi 5243 days ago
These are guidelines and not unbreakable rules. I think it's fine to have unsubscribe link change the state of the resource. [And personally, I would only flag the user for not sending emails, not delete his email altogether.]
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moozeek 5243 days ago
> [And personally, I would only flag the user for not sending emails, not delete his email altogether.]

Sure, just wanted to make my point. In reality you move the subscriber from "subscribed" to "unsuscribed" or something like this...

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eCa 5243 days ago
In my opinion, you should not initiate a removal from an email. In part due to this. Instead you give the recipient a link to a web page where you have a form that sends either a POST or DELETE to the application.

"Should not" used in the rfc2119 definition. There are always exceptions.

http://www.ietf.org/rfc/rfc2119.txt

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DougWebb 5243 days ago
It depends on where the link is. If it's in a web page and the user's browser supported any valid method in forms, you could use a form with method="DELETE" and action="uri for user's subscription", with a submit button styled to look like a link. For browsers that don't support the DELETE method in forms, you can add a hidden input _method=DELETE which is the semi-standard workaround for incomplete browser support. (Your service has to look for _method when it gets a POST and react accordingly.)

If the link is in an email, a form probably won't work. Email clients are still worse than browsers when it comes to styling buttons to look like links. In that case, you can use a real link, but add the _method=DELETE to the url parameters. You service can then look for _method on GET requests too. But it's bad and hacky to change a GET into a DELETE, so you really should just use the link to display a web page, then delete with a DELETE or POST from there. That's what most unsubscribe links in emails do anyway.

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