I want to put a check on Permission level "Owner" from enum map

Questions / Help
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1 
I am getting project permissions access level and accessing it through Enum.map(). I want to put a check if it is "Owner" how do I do that from a map. How do I do that


project_permissions = ProjectPermissions.list_project_permissions()

        Enum.map(project_permissions, fn %{id: id, access_level: access_level} ->
          {access_level, id} |> IO.inspect()
        end)

{"Owner", 1}
{"Moderator", 2}
{"Viewer", 3}
2

Can you rephrase or provide a more specific example of what you’re asking for?

This is not clear (to me, at least) if you want to select a checkbox in the UI, or confirm if the list contains an item with the permission "Owner"

3

confirm if the list contains an item with the permission "Owner"

4

Depending on what you need I will give you few examples …

Let’s start with initial data:

iex> project_permissions = [
  %{access_level: "Owner", id: 1},
  %{access_level: "Moderator", id: 2},
  %{access_level: "Viewer", id: 3}
]
[
  %{access_level: "Owner", id: 1},
  %{access_level: "Moderator", id: 2},
  %{access_level: "Viewer", id: 3}
]

We can simply check if in said project_permissions list are any items with access_level set to Owner:

iex> Enum.any?(project_permissions, & &1.access_level == "Owner")
true

You can also easily filter results by map value:

iex> Enum.filter(project_permissions, & &1.access_level == "Owner")
[%{access_level: "Owner", id: 1}]

Alternatively you can use for with filter:

iex> for %{access_level: access_level, id: id} <- project_permissions, access_level == "Owner", do: {access_level, id}
[{"Owner", 1}]

Helpful resources:

  1. Enum.any?/2
  2. Enum.filter/2
  3. for special form
  4. Comprehensions article at elixir-lang.org
1 Like
5

It is a similar solution to your other question :slightly_smiling_face:

permissions =
  Enum.map(project_permissions, fn %{id: id, access_level: access_level} ->
    {access_level, id} |> IO.inspect()
  end)

Enum.any?(permissions, fn {permission, _id} -> permission == "Owner" end)
# or
Enum.find(permissions, fn {permission, _id} -> permission == "Owner" end)

A more direct way to find the full ProjectPermission struct in one pass:

Enum.find(project_permissions, fn %{access_level: access_level} -> access_level == "Owner" end)

or instead of pulling a list of all records from the database and finding the one you want, you can more efficiently query the one record you want directly from the database

def get_project_permission_by_access_level(access_level) do
  Repo.get_by(ProjectPermission, access_level: access_level)
end

get_project_permission_by_access_level("Owner")
6

Now i need to put it in condition and list the project with owner permissions

7

I will try this one