Rails 4 Pundit - policies in parent models

Question

I'm trying to use rails 4 with pundit policies.

I have a profile model and a projects model. Projects are HABTM with profiles.

I have a project policy, that has a create? action (set to true).

In my profile show page, I want to allow users to create new projects, if they project policy create action allows it.

<% if policy(@project).create? %>
  <%= link_to 'CREATE A PROJECT', new_project_path, :class=>"btn btn-info"  %>
<% end %>

When I try this, i get a nil policy error. Is it because you can't use project actions inside profile views? If so, how do I fix it so that I can display a new project button on my profile show page?

Is `@project` defined in the controller that's rendering this page? — miler350, Apr 03 '16 at 05:11
That means your conditional is really saying this: `<% if policy(nil).create? %>`. Which, I'd assume, is causing your nil policy error. — miler350, Apr 03 '16 at 05:18
ah - i see. it doesnt work though if i write if policy(profile.project).create?. Any ideas for how to make that work? — Mel, Apr 03 '16 at 07:44

score 0 · Accepted Answer · answered Apr 03 '16 at 07:34

0

You can use ProjectPolicy.new(current_user, @project).create? to specific ProjectPolicy.

However, like @miler350 said, @project might be nil. (for example: User has no project created). Make sure your ProjectPolicy#create? handles nil properly.

answered Apr 03 '16 at 07:34

tangrufus

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How do I do that? I just want to add a link to create a new project if the profile is permitted to create a new project. – Mel Apr 03 '16 at 07:45
maybe `<% if policy(Project).create? %>` is more appropriate in your case – tangrufus Apr 03 '16 at 11:51

Rails 4 Pundit - policies in parent models

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