Begin/rescue not working?

Rails
1

Can someone help me with the following code? I’m purposely typing in a
bogus rga number, and the begin/rescue block should catch that and
inform the user, right?

But when I run this with a bogus number, I get the “Render and/or
redirect were called multiple times in this action” error.

What am I doing wrong here?

Thanks!

def assign
@users = User.find(:all, :order => ‘name’)

if request.post?
rga_number = params[:rga_number]
user_id = params[:user_id]

begin
  rga = Rga.find(params[:rga_number])
rescue
  flash[:notice] = 'There is not a RGA with that number'
  redirect_to :action => 'list'
end

new_RGA = RgaEvent.new
new_RGA.rga_id = rga_number
new_RGA.rga_number = rga_number
new_RGA.user_id = user_id

if new_RGA.save
  user_name = User.find(user_id).name
  flash[:notice] = 'RGA assigned to user ' + user_name
  redirect_to :action => 'list'
end

end
end

2

On 10/31/07, Jason F. [email protected] wrote:

Can someone help me with the following code? I’m purposely typing in a
bogus rga number, and the begin/rescue block should catch that and
inform the user, right?

It does; that’s not the problem.

if request.post?
rga_number = params[:rga_number]
user_id = params[:user_id]

begin
  rga = Rga.find(params[:rga_number])
rescue
  flash[:notice] = 'There is not a RGA with that number'
  redirect_to :action => 'list'

You need to “return” right here, or execution continues on. That’s why
you’re getting the error message.

You probably should rescue ActiveRecord::RecordNotFound. If a
different exception were to be raised, you would never know it.

3

Ok,

I’ve changed the code to:

begin
rga = Rga.find(params[:rga_number])
rescue ActiveRecord::RecordNotFound
flash[:notice] = ‘There is not a RGA with that number’
redirect_to :action => ‘list’
end

Still getting the error. You’re dealing with a newbie here: What do
you mean by ‘return’?

4

On 10/31/07, Jason F. [email protected] wrote:

end

Still getting the error. You’re dealing with a newbie here: What do
you mean by ‘return’?

I mean to add a “return” statement:

  redirect_to :action => 'list'
  return       # <-- add this line

end

5

On 31 Oct 2007, at 14:07, Jason F. wrote:

one, so I’m still confused as to why this case required a return in
it.

This has nothing to do with begin/rescue. It has everything to do with
the fact that you should redirect or render precisely once per action,
whereas in you original code you would end up doing a redirect in the
rescue block and then again if bit below.

Fred

6

you should redirect or render precisely once per action,

How do you possibly check for multiple errors in an action? Aren’t you
supposed to redirect after detecting one?

7

I mean to add a “return” statement:

  redirect_to :action => 'list'
  return       # <-- add this line

end

Worked perfectly! Thanks!

I’ve used the begin/rescue/end in other controllers like I did in this
one, so I’m still confused as to why this case required a return in it.

8

On 31 Oct 2007, at 14:24, Jason F. wrote:

you should redirect or render precisely once per action,

How do you possibly check for multiple errors in an action? Aren’t
you
supposed to redirect after detecting one?
OK, so at a basic level, this will result in the double render error

def foo
redirect_to :action => ‘bar’
redirect_to :action => ‘bar’
end

so
def foo
if …
redirect_to :action => ‘bar’
end

if …
redirect_to :action => ‘bar’
end
end

will also cause errors unless the 2 conditions are mutually exclusive

You need to do something like. Either return after redirecting/
rendering or do whatever you have to do to ensure that you don’t do
it more than once per action, for example

def foo
if …
redirect_to :action => ‘bar’
return
end

if …
redirect_to :action => ‘bar’
return
end
end

Fred

9

Ok, that makes sense.

Thanks guys!