Authorization error when project is `nil` or invalid `project_id`

[mtuchi]

Describe the bug

When a user enter a valid project uuid in url but that project uuid does not exist an error will be thrown

I have reproduced this locally on main:

• [x] Yes
• [ ] No

To Reproduce Steps to reproduce the behavior:

1. Go to project dashboard
2. Click on address bar and change the last character of project uuid eg. abb2e086-8d79-42b2-94d1-b56c67cef5fb
3. Press enter
4. See error

[error] #PID<0.1145.0> running Phoenix.Endpoint.SyncCodeReloadPlug (connection #PID<0.1122.0>, stream id 7) terminated
Server: localhost:4000 (http)
Request: GET /projects/abb2e086-8d79-42b2-94d1-b56c67cef5fb/w
** (exit) an exception was raised:
    ** (FunctionClauseError) no function clause matching in Lightning.Policies.ProjectUsers.authorize/3
        (lightning 0.5.2) lib/lightning/policies/project_users.ex:40: Lightning.Policies.ProjectUsers.authorize(:access_project, #Lightning.Accounts.User<__meta__: #Ecto.Schema.Metadata<:loaded, "users">, id: "3ec80ce9-a4db-4115-92f8-b8fc3b87bf2b", first_name: "Amy", last_name: "Admin", email: "demo@openfn.org", confirmed_at: nil, role: :user, disabled: false, scheduled_deletion: nil, credentials: #Ecto.Association.NotLoaded<association :credentials is not loaded>, project_users: #Ecto.Association.NotLoaded<association :project_users is not loaded>, projects: #Ecto.Association.NotLoaded<association :projects is not loaded>, inserted_at: ~N[2023-05-11 15:54:17], updated_at: ~N[2023-05-11 15:54:17], ...>, nil)
        (bodyguard 2.4.2) lib/bodyguard.ex:28: Bodyguard.permit/4
        (lightning 0.5.2) lib/lightning/policies/permissions.ex:62: Lightning.Policies.Permissions.can?/4
        (lightning 0.5.2) lib/lightning_web/hooks.ex:26: LightningWeb.Hooks.on_mount/4
        (phoenix_live_view 0.18.18) lib/phoenix_live_view/lifecycle.ex:149: anonymous fn/4 in Phoenix.LiveView.Lifecycle.mount/3
        (phoenix_live_view 0.18.18) lib/phoenix_live_view/lifecycle.ex:215: Phoenix.LiveView.Lifecycle.reduce_socket/3
        (phoenix_live_view 0.18.18) lib/phoenix_live_view/utils.ex:389: anonymous fn/6 in Phoenix.LiveView.Utils.maybe_call_live_view_mount!/5
        (telemetry 1.2.1) /Users/openfn/Workspace/Lightning/deps/telemetry/src/telemetry.erl:321: :telemetry.span/3
        (phoenix_live_view 0.18.18) lib/phoenix_live_view/static.ex:278: Phoenix.LiveView.Static.call_mount_and_handle_params!/5
        (phoenix_live_view 0.18.18) lib/phoenix_live_view/static.ex:119: Phoenix.LiveView.Static.render/3
        (phoenix_live_view 0.18.18) lib/phoenix_live_view/controller.ex:39: Phoenix.LiveView.Controller.live_render/3
        (phoenix 1.7.2) lib/phoenix/router.ex:430: Phoenix.Router.__call__/5
        (lightning 0.5.2) lib/lightning_web/endpoint.ex:1: LightningWeb.Endpoint.plug_builder_call/2
        (lightning 0.5.2) lib/lightning_web/endpoint.ex:1: LightningWeb.Endpoint."call (overridable 3)"/2
        (lightning 0.5.2) lib/plug/debugger.ex:136: LightningWeb.Endpoint."call (overridable 4)"/2
        (lightning 0.5.2) lib/lightning_web/endpoint.ex:1: LightningWeb.Endpoint.call/2
        (phoenix 1.7.2) lib/phoenix/endpoint/sync_code_reload_plug.ex:22: Phoenix.Endpoint.SyncCodeReloadPlug.do_call/4
        (plug_cowboy 2.6.1) lib/plug/cowboy/handler.ex:11: Plug.Cowboy.Handler.init/2
        (cowboy 2.9.0) /Users/openfn/Workspace/Lightning/deps/cowboy/src/cowboy_handler.erl:37: :cowboy_handler.execute/2
        (cowboy 2.9.0) /Users/openfn/Workspace/Lightning/deps/cowboy/src/cowboy_stream_h.erl:306: :cowboy_stream_h.execute/3

Screenshots

Additional context This bug happens when project is nil when we're fetching the project in this line https://github.com/OpenFn/Lightning/blob/main/lib/lightning_web/hooks.ex#L19

Proposed solution Check if project exist before checking for permission

if is_nil(project) do
      {:halt, redirect(socket, to: "/") |> put_flash(:nav, :not_found)}
    else
      projects =
        Lightning.Projects.get_projects_for_user(socket.assigns.current_user)

      can_access_project =
        ProjectUsers
        |> Permissions.can?(
          :access_project,
          socket.assigns.current_user,
          project
        )

      if can_access_project do
        {:cont,
         socket
         |> assign_new(:project, fn -> project end)
         |> assign_new(:projects, fn -> projects end)}
      else
        {:halt, redirect(socket, to: "/") |> put_flash(:nav, :no_access)}
      end
    end

[mtuchi]

Also when a user enter an invalid uuid the following error will be thrown

See screen-record

https://github.com/OpenFn/Lightning/assets/6592749/e8b4043d-4d9c-4117-9a33-085c35ee4c20

[taylordowns2000]

@mtuchi , @elias-ba , this is already handled in a "good enough" sort of way on app.openfn.org.

in Phoenix, you only see that page that mtuchi shows when you're running an app on your local machine in dev mode. (and it's a great screen to see!)