How to return JSON of an Ecto result in Phoenix-CodePudding

I am new to Phoenix, and using it for a backend, and currently am trying to return the result of Repo.all as JSON to the user.

I have this working in the following way (in user_controller.ex)

def index(conn, _params) do
    result = Repo.all(User)
    users = Enum.map(result
        fn user ->
            Map.take(user, [:id, :firstname, :lastname, :username])
        end)
    conn |> json(users)
end

but this feels like I'm taking unnecessary steps when there may just be a simple function.

Is this the most idiomatic way to send an Ecto result as JSON?

CodePudding user response：

You have multiple ways to do it, depending on what you exactly want, for example :

If you want every fields you can use :

User
|> Repo.all()
|> Enum.map(fn user -> 
  user |> Map.from_struct
end)

This will return all User and apply Map.from_struct to every user found.

If you want only specific fields, you can use :

from(
    u in User,
    select: map(u, [:id, :email])
) |> Repo.all()

This will return an array of map containing only select fields. (Ecto.Query.API.map)