My mix.exs dependencies (partial list):
{:ex_aws, “~> 2.1”},
{:ex_aws_dynamo, “~> 4.0”},
{:hackney, “~> 1.9”},
{:configparser_ex, “~> 4.0”}I created an Ecto.Schema:

I can create dyanmo tables, insert, update, and delete records just fine as long as the data records are derived from generic structs.

However, when I create an Ecto.Schema

defmodule IntandemWww.Users.User do
use Ecto.Schema
import Ecto.Changeset

@derive [ExAws.Dynamo.Encodable]

schema “users” do
field :name, :string, virtual: true
field :first_name, :string
field :middle_name, :string
field :last_name, :string
field :condition, :string
field :email, :string
field :phone, :string
field :status, :string
field :mentor, :string
field :enrollment_date, :string

timestamps()

end
end

Instance looks like this (note the “meta” attribute):

%Users.User{
meta: #Ecto.Schema.Metadata<:built, “users”>,
id: nil,
name: nil,
first_name: nil,
middle_name: nil,
last_name: nil,
condition: nil,
email: nil,
phone: nil,
status: nil,
mentor: nil,
enrollment_date: nil,
inserted_at: nil,
updated_at: nil
}

Then when I try to Encode it (with some actual data set though):

Dynamo.Encoder.encode!(new_user)

I get the following error:

** (Protocol.UndefinedError) protocol ExAws.Dynamo.Encodable not implemented for #Ecto.Schema.Metadata<:built, “users”> of type Ecto.Schema.Metadata (a struct). This protocol is implemented for the following type(s): Atom, BitString, Float, HashDict, Users.User, Integer, List, Map, MapSet, User
(ex_aws_dynamo 4.2.1) lib/ex_aws/dynamo/encodable.ex:1: ExAws.Dynamo.Encodable.impl_for!/1
(ex_aws_dynamo 4.2.1) lib/ex_aws/dynamo/encodable.ex:5: ExAws.Dynamo.Encodable.encode/2
(ex_aws_dynamo 4.2.1) lib/ex_aws/dynamo/encodable.ex:87: anonymous fn/2 in ExAws.Dynamo.Encodable.Map.do_encode/1
(stdlib 4.0.1) maps.erl:411: :maps.fold_1/3
(ex_aws_dynamo 4.2.1) lib/ex_aws/dynamo/encodable.ex:64: ExAws.Dynamo.Encodable.Map.encode/2

I looked through the encoder.ex in the ex_aws_dynamo dependency and the “meta” field is obviously not accounted for during encoding.

Is anyone using Ecto.Schema with Dynamo and if so how? Is this an oversight or were they not meant to ever work together?

I do not see any usage of the “options” that are passed to “encode” functions. Would a valid solution be to add “ignore_fields” as an array of fields to skip over?