elixir-Exto-naive_日期时间强制转换错误

在我的EXTO模型中，我需要在字段中指定：user\u timestamp从unix\u time转换的时间。 迁移：

  def change do
    alter table(:operations) do
      add :user_timestamp, :naive_datetime, null: false
    end
  end

我的手术

  schema "operations" do
    field :sum, :float
    field :name, :string
    field :user_timestamp, :naive_datetime

    timestamps()
  end

  def changeset(struct, params \\ %{}) do
    struct
    |> cast(params, [:name, :sum, :user_timestamp])
    |> validate_required([:sum, :user_timestamp])
    |> convert_unix_time_to_ecto
  end

  defp convert_unix_time_to_ecto(changeset) do
    put_change(changeset, :user_timestamp, Ecto.DateTime.from_unix!(changeset.changes.user_timestamp, :seconds) |> Ecto.DateTime.to_naive())
  end

但是，当我尝试添加具有用户时间戳的要求时，我得到一个错误：

[error] #PID<0.492.0> running MyApp.Endpoint terminated
Server: localhost:4000 (http)
Request: POST /api/v1/operations
** (exit) an exception was raised:
    ** (FunctionClauseError) no function clause matching in Ecto.Type.cast_naive_datetime/1
        (ecto) lib/ecto/type.ex:761: Ecto.Type.cast_naive_datetime(1492722276)
        (ecto) lib/ecto/changeset.ex:523: Ecto.Changeset.cast_field/8
        (ecto) lib/ecto/changeset.ex:482: Ecto.Changeset.process_param/8
        (elixir) lib/enum.ex:1325: Enum."-map_reduce/3-lists^mapfoldl/2-0-"/3
        (elixir) lib/enum.ex:1325: Enum."-map_reduce/3-lists^mapfoldl/2-0-"/3
        (ecto) lib/ecto/changeset.ex:450: Ecto.Changeset.do_cast/7
        (my_app) web/models/operation.ex:25: MyApp.Operation.changeset/2
        (my_app) web/models/operation.ex:32: MyApp.Operation.create_changeset/2
        (my_app) web/controllers/v1/operation_controller.ex:25: MyApp.V1.OperationController.create/2
        (my_app) web/controllers/v1/operation_controller.ex:1: MyApp.V1.OperationController.action/2
        (my_app) web/controllers/v1/operation_controller.ex:1: MyApp.V1.OperationController.phoenix_controller_pipeline/2
        (my_app) lib/my_app/endpoint.ex:1: MyApp.Endpoint.instrument/4
        (my_app) lib/phoenix/router.ex:261: MyApp.Router.dispatch/2
        (my_app) web/router.ex:1: MyApp.Router.do_call/2
        (my_app) lib/my_app/endpoint.ex:1: MyApp.Endpoint.phoenix_pipeline/1
        (my_app) lib/plug/debugger.ex:123: MyApp.Endpoint."call (overridable 3)"/2
        (my_app) lib/my_app/endpoint.ex:1: MyApp.Endpoint.call/2
        (plug) lib/plug/adapters/cowboy/handler.ex:15: Plug.Adapters.Cowboy.Handler.upgrade/4
        (cowboy) /home/mars/phoenix_projects/my_app/deps/cowboy/src/cowboy_protocol.erl:442: :cowboy_protocol.execute/4

[错误]#运行MyApp的PID。终结点已终止
服务器：本地主机：4000（http）
请求：POST/api/v1/operations
**（退出）引发了一个异常：
**（FunctionClauseError）在exto.Type.cast\u naive\u datetime/1中没有匹配的函数子句
（exto）lib/exto/type.ex:761:exto.type.cast\u naive\u datetime（149272276）
（exto）lib/exto/changeset.ex:523:exto.changeset.cast_字段/8
（exto）lib/exto/changeset.ex:482:exto.changeset.process_param/8
（elixir）lib/enum.ex:1325:enum.“-map_reduce/3-lists^mapfoldl/2-0-”/3
（elixir）lib/enum.ex:1325:enum.“-map_reduce/3-lists^mapfoldl/2-0-”/3
（exto）lib/exto/changeset.ex:450:exto.changeset.do_cast/7
（my_app）web/models/operation.ex:25:MyApp.operation.changeset/2
（my_app）web/models/operation.ex:32:MyApp.operation.create_变更集/2
（my_app）web/controllers/v1/operation_controller.ex:25:MyApp.v1.OperationController.create/2
（my_app）web/controllers/v1/operation_controller.ex:1:MyApp.v1.OperationController.action/2
（my_app）web/controllers/v1/operation_controller.ex:1:MyApp.v1.OperationController.phoenix_controller_管道/2
（my_app）lib/my_app/endpoint.ex:1:MyApp.endpoint.instrument/4
（我的应用程序）lib/phoenix/router.ex:261:MyApp.router.dispatch/2
（my_应用程序）web/router.ex:1:MyApp.router.do_call/2
（my_app）lib/my_app/endpoint.ex:1:MyApp.endpoint.phoenix_管道/1
（my_app）lib/plug/debugger.ex:123:MyApp.Endpoint.“调用（可重写3）”/2
（my_app）lib/my_app/endpoint.ex:1:MyApp.endpoint.call/2
（plug）lib/plug/adapters/cowboy/handler.ex:15:plug.adapters.cowboy.handler.upgrade/4
（牛仔）/home/mars/phoenix_projects/my_app/deps/cowboy/src/cowboy_protocol.erl:442:：cowboy_protocol.execute/4

---

如何更正此错误？

在转换代码有机会运行之前，

转换失败

将
：用户\u时间戳
从cast字段列表中保留，并在
验证所需的
之前使用带有转换值的
put\u change

def changeset(struct, params \\ %{}) do

    struct
    |> cast(params, [:name, :sum])
    |> convert_unix_time_to_ecto(params["user_timestamp"])
    |> validate_required([:sum, :user_timestamp])

  end

  defp convert_unix_time_to_ecto(changeset, nil), do: changeset    
  defp convert_unix_time_to_ecto(changeset, timestamp) do
    datetime = 
       timestamp
       |> DateTime.from_unix!(:seconds)
       |> DateTime.to_naive()

    put_change(changeset, :user_timestamp, datetime)
  end

一个选择是使用