Problem updating changesets with relations.

[itSQualL]

I'm trying to use PaperTrail.update to update a record that has a has_many relation, but it is triggering the next error:

web_1  | #Ecto.Changeset<action: nil,                                                                                                          [4/4594]
web_1  |  changes: %{current_status: 49,
web_1  |    key_results: [#Ecto.Changeset<action: :update,
web_1  |      changes: %{values: %{"current_value" => 49, "desired_value" => 100}},
web_1  |      errors: [], data: #Performancex.KeyResult<>, valid?: true>]}, errors: [],
web_1  |  data: #Performancex.Objective<>, valid?: true>
web_1  | [debug] QUERY OK db=1.3ms
web_1  | begin []
web_1  | [debug] QUERY OK db=2.2ms
web_1  | UPDATE "objectives" SET "current_status" = $1, "updated_at" = $2 WHERE "id" = $3 [49, {{2017, 5, 4}, {10, 40, 57, 718198}}, 1]
web_1  | [debug] QUERY OK db=0.4ms
web_1  | UPDATE "key_results" SET "values" = $1, "updated_at" = $2 WHERE "id" = $3 [%{"current_value" => 49, "desired_value" => 100}, {{2017, 5, 4}, {1
0, 40, 57, 720656}}, 1]
web_1  | [debug] QUERY ERROR db=5.3ms
web_1  | INSERT INTO "versions" ("event","item_changes","item_id","item_type","originator_id","inserted_at") VALUES ($1,$2,$3,$4,$5,$6) RETURNING "id",
 "origin" ["update", %{current_status: 49, key_results: [#Ecto.Changeset<action: :update, changes: %{values: %{"current_value" => 49, "desired_value" =
> 100}}, errors: [], data: #Performancex.KeyResult<>, valid?: true>]}, 1, "Objective", 2, {{2017, 5, 4}, {10, 40, 57, 721334}}]
web_1  | [debug] QUERY OK db=0.1ms
web_1  | rollback []
web_1  | [info] Sent 500 in 53ms
web_1  | [error] #PID<0.644.0> running Performancex.Endpoint terminated
web_1  | Server: localhost:4000 (http)
web_1  | Request: PUT /api/v1/performance/objectives/1
web_1  | ** (exit) an exception was raised:
web_1  |     ** (Poison.EncodeError) unable to encode value: {nil, "key_results"}
web_1  |         (poison) lib/poison/encoder.ex:354: Poison.Encoder.Any.encode/2
web_1  |         (poison) lib/poison/encoder.ex:213: anonymous fn/4 in Poison.Encoder.Map.encode/3
web_1  |         (poison) lib/poison/encoder.ex:214: Poison.Encoder.Map."-encode/3-lists^foldl/2-0-"/3
web_1  |         (poison) lib/poison/encoder.ex:214: Poison.Encoder.Map.encode/3
web_1  |         (poison) lib/poison/encoder.ex:213: anonymous fn/4 in Poison.Encoder.Map.encode/3
web_1  |         (poison) lib/poison/encoder.ex:214: Poison.Encoder.Map."-encode/3-lists^foldl/2-0-"/3
web_1  |         (poison) lib/poison/encoder.ex:214: Poison.Encoder.Map.encode/3
web_1  |         (poison) lib/poison/encoder.ex:213: anonymous fn/4 in Poison.Encoder.Map.encode/3
web_1  |         (poison) lib/poison/encoder.ex:214: Poison.Encoder.Map."-encode/3-lists^foldl/2-0-"/3
web_1  |         (poison) lib/poison/encoder.ex:214: Poison.Encoder.Map.encode/3
web_1  |         (poison) lib/poison/encoder.ex:232: anonymous fn/3 in Poison.Encoder.List.encode/3
web_1  |         (poison) lib/poison/encoder.ex:233: Poison.Encoder.List.encode/3
web_1  |         (poison) lib/poison/encoder.ex:213: anonymous fn/4 in Poison.Encoder.Map.encode/3
web_1  |         (poison) lib/poison/encoder.ex:214: Poison.Encoder.Map."-encode/3-lists^foldl/2-0-"/3
web_1  |         (poison) lib/poison/encoder.ex:214: Poison.Encoder.Map.encode/3
web_1  |         (poison) lib/poison.ex:41: Poison.encode!/2
web_1  |         (ecto) /performancex/deps/postgrex/lib/postgrex/type_module.ex:717: Ecto.Adapters.Postgres.TypeModule.encode_params/3

It works fine with Repo.update so, do you have any idea that could be happening?

[itSQualL]

The problem seems to be here: https://github.com/izelnakri/paper_trail/blob/master/lib/paper_trail.ex#L278-Lundefined

That returns:

item_changes: %{current_status: 19,
  key_results: [#Ecto.Changeset<action: :update,
  changes: %{values: %{"current_value" => 19, "desired_value" => 100}},
  errors: [], data: #Performancex.KeyResult<>, valid?: true>]
}

And fails when you try to do @repo.insert(version)

[izelnakri]

item_changes should represent a simple map of the changes automatically generated from your changeset functions. %PaperTrail.Version{item_changes: %{}} is essentially the %Changeset{changes: %{}}. I've never seen a case where you would have a changeset inside a changeset.changes, it should always be a simple map. Are you trying to update relationships in one go? Can you provide the your controller code and the changeset you are updating?

Seems like an interesting edge-case I would really like to know how you've ended up with a changeset inside a changeset. Lastly, thanks for reporting!

[itSQualL]

Thank you for answering

I have the objective and the params

objective is a struct returned from Repo.get
params are like:

%{
  current_status: 2,
  key_results: [
    id: 2,
    values: %{
      current_value: 15,
      desired_value: 100
    }
  ]
}

Then, I'm just doing:

Objective.changeset_for_update(objective, params)
|> PaperTrail.update(originator: current_user)

Objective module:

def changeset_for_update(struct, params \\ {}) do
  struct
  |> cast(params, [:current_status, :assessment])
  |> cast_assoc(:key_results)
  |> validate_required([:current_status, :key_results])
end

[izelnakri]

related discussion: #18. Im closing this issue now.