borybar
Hi,
I am displaying users cpm based on their submitted form. It all works until I am creating a new user who doesn’t have such cpm yet. Then I get an error. I understand that I need to use case in which I check either there is a cpm or not, if not I return a link to needed form. I was wondering how to do it, as I am not sure what I should write in such case.
My page_controller:
def index(conn, _params, current_user) do
user = current_user.id
user_pps = Cpm.list_user_pp(current_user)
user_pp = Cpm.get_user_pp!(current_user, user)
user_bmr = Bmr.bmr_for_user(user_pp)
user_cpm = Float.floor(Bmr.cpm_for_user(user_pp, user_bmr))
case user_cpm do
{:ok} -> returns first cpm
{:error} -> returns a link to a form
render(conn, "index.html", user: user, userp_pps: user_pps, user_cpm: user_cpm)
Thanks for help!
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kokolegorille
You can always redirect in case there is no user_cpm.
Another way is to use a conditional in the template… like this.
You case miss an end
borybar
Thanks for the reply!
What if I don’t want to redirect from start? I want to keep a user on the front page so he has access to different things, only if he wants to he can click a button to redirect to my form
kokolegorille
Then try the code I put in my last post
borybar
I have tried your recommendation but I guess I am doing something wrong. I will be very grateful for your help.
This is my template now:
What I get when I try to visit my main page is:
borybar
I suspect that it’s not even getting to my
user_cpmvariable as it doesn’t have a value inuservariable in my controller as there is no users in db.kokolegorille
Try replacing @current_user with assigns[:current_user]
The first will fail if not set, the second will return nil.
You cannot use variable that have not been set.
If current_user is not set, it will fail with the error You see…
borybar
So if I can’t use variable that have not been set yet, what can I do? Use
case?kokolegorille
No, use assigns[:current_user] in the template…
or test that the value exists.
You cannot use current_user.id if it is not set.
borybar
Thank you for help. I managed to resolve my issue by using
case