Do I have to care about other methods than GET and POST?

Rails
1

Hi all

Sometimes I check in a controller if the method is GET or POST. But
afaik there are other methods - do I have to care about them?

Is the following enough?

if request.get?
…
elsif request.post?
…
end

Or do I have to add also an else block?

if request.get?
…
elsif request.post?
…
else
raise “Boah!”
end

Thanks for infos
Josh

2

Or do I have to add also an else block?

if request.get?
…
elsif request.post?
…
else
raise “Boah!”
end

IMO, defensive programming says there should almost always be an else
in these type of constructs unless they’re being used to prepare
special cases for the code that follows (code which doesn’t care if
there’s neither a GET nor POST).

So, what will your program do if neither of the first two are
satisfied? If the code must have one or the other, then yes, you need
an else. If the code modifies something in the cases of GET/POST and
otherwise runs just fine if there is no GET/POST, then you do not
need the else (because it would halt processing you’re expecting to
happen).

– gw

3

Just to add to the last reply, there are now other very commonly used
methods. Namely PUT, DELETE and sometimes HEAD. Rails 1.2 started this
and Rails 2.0 will go beyond even what’s being done in 1.2. Not adding
more methods, but “scaffold_resource” is now simply “scaffold.” When
generating scaffolding you will get RESTful controllers by default
using the full set of HTTP methods.

However, keep in mind that if the request is being generated from a
web form it will use GET or POST (at least until browsers get smart
enough to handle the other methods). That being said in a modern Rails
application you can’t count of the request coming from a HTML form. It
just might be coming from another client that does understand the full
REST method set, or even from a command line on the terminal.

4

If you really need to check for specific http verbs, the else is a
must. Browsers are not smart enough to send anything than
GET/POST, but other HTTP clients are, e.g.: wget, curl, just to
name a few. curl can also send invalid http verbs.

Rails provide a much better way of doing http verb checks, the
verify method [1]. It also allow you to check for http/session
parameters and xhr.

If verify method not suit your needs, i will try to use a more
idiomatic
code like this.

request_is(request) do |verb|
verb.post { do_something1 }
verb.get { do_something2 }
verb.head { do_somethind3 }
…
end

The main idea is to encapsulate common behaviour for all actions
in a request proxy. I mean, logging, mail to administrators, or
whathever else you need to do, and pass the other method calls
to the real request instance through Object#send

references:
[1]
http://api.rubyonrails.com/classes/ActionController/Verification/ClassMethods.html

5

Thank you, guys.