Drab partials template

Hi guys,

Following up on this github issue where @grych has been kindly helping:

I have been trying to get this right but still unable to make it work.

I have the basic controller, commander setup but with nested partials as follows:

Controller renders → new.html.drab template
new.html.drab template renders → form.html.drab template
the form.html.drab template renders → _invoices.html.drab template
invoices.html.drab template renders → _invoice_details.html.drab template

I am setting a drab-change event handler in a input checkbox in the last partial invoice_details.

This event handler triggers a update to a assign (po_grantotal) and this assign is located in the form.html.drab template

This are the form.html.drab template assigns:

iex(6)> socket |> assigns("form.html")
[:action, :changeset, :conn, :currency_us, :invoices, :parent, :po_grantotal]

This is a peek at that assign:

iex(7)> socket |> peek("form.html", :po_grantotal)
{:ok, 0}

So my poke call is as follows:

poke socket, "form.html", po_grantotal: 1000

With this setup I get the following error:

** (Protocol.UndefinedError) protocol Enumerable not implemented for nil. This protocol is implemented for: DBConnection.PrepareStream, DBConnection.Stream, Date.Range,
Ecto.Adapters.SQL.Stream, File.Stream, Floki.HTMLTree, Function, GenEvent.Stream, HashDict, HashSet, IO.Stream, List, Map, MapSet, Postgrex.Stream, Range, Scrivener.Page
, Stream, Timex.Interval
    (elixir) lib/enum.ex:1: Enumerable.impl_for!/1
    (elixir) lib/enum.ex:141: Enumerable.reduce/3
    (elixir) lib/enum.ex:1919: Enum.map/2
    (epr) lib/epr_web/templates/payment_order/form.html.drab:76: anonymous fn/2 in EprWeb.PaymentOrderView."form.html"/1
    (phoenix_html) lib/phoenix_html/form.ex:288: Phoenix.HTML.Form.form_for/4
    (epr) lib/epr_web/templates/payment_order/form.html.drab:1: EprWeb.PaymentOrderView."form.html"/1
    (phoenix) lib/phoenix/view.ex:332: Phoenix.View.render_to_iodata/3
    (phoenix) lib/phoenix/view.ex:339: Phoenix.View.render_to_string/3
    (drab) lib/drab/live.ex:683: Drab.Live.rerender_template/4
    (drab) lib/drab/live.ex:638: Drab.Live.process_poke/9

Is this a correct setup? What am I doing wrong?

Thanks in advance for your help.

Best regards,

1 Like

Could you pls try

iex> socket |> peek("form.html", :changeset)

Something becomes nil, I am worried that it might be a changeset…

This is the peek changeset result:

iex(4)> socket |> peek("form.html", :changeset)
{:ok,
 #Ecto.Changeset<
   action: nil,
   changes: %{},
   errors: [
     date: {"can't be blank", [validation: :required]},
     concept: {"can't be blank", [validation: :required]},
     check_number: {"can't be blank", [validation: :required]},
     bank_account_id: {"can't be blank", [validation: :required]}
   ],
   data: #Epr.Payments.PaymentOrder<>,
   valid?: false
 >}

I also peek all the assigns for this form and none where nil.

This are all the assigns:

iex(12)> socket |> assigns("form.html")
[:action, :changeset, :conn, :currency_us, :invoices, :parent, :po_grantotal]

Is the form_for only enumerable you did use in form.html? Maybe we are checking the wrong place.

Yes, I use the form_for in the “form.html” template.

I am going to try something else with the nested templates.

It looks like a bug, but I can’t reproduce it.

Could you please inspect the @changeset and @action in form.html?
Also, could you check from the JS console, if the changeset exists in the __drab.assigns object?

This is the result:

form.html.drab

<%= form_for @changeset, @action, fn f -> %>
<%= inspect(@changeset) %>
<p>---------------------</p>
<%= inspect(@action) %>
  <div class="row">
    <div class="col-md-12">
      <%= render "_invoices.html", conn: @conn, invoices: @invoices, parent: @parent %>
    </div>
  </div>
    ............

result printed out in the browser page

#Ecto.Changeset&lt;action: nil, changes: %{}, errors: [date: {"can't be blank", [validation: :required]}, concept: {"can't be blank", [validation: :required]}, check_number: {"can't be blank", [validation: :required]}, bank_account_id: {"can't be blank", [validation: :required]}], data: #Epr.Payments.PaymentOrder&lt;&gt;, valid?: false&gt;

---------------------

"/contracts/2/payment_orders"

This is the Google Chrome Console output for _drab

1. assigns:

  1. ge4tcmbtge2dkmzz:

    1. invoices: {document: "QTEyOEdDTQ.rkO2qTvBKpBncBjBOUNNhhYj7hrcS__s-bMZkYU…GoDtSb4T2CJn5yhopxEb6dPUAV.1JZQG4HEUiGSDOPx0Vmdug"}
    2. parent: {document: "QTEyOEdDTQ.Ar-AaS6DIYytU2srD6pveNYKX862GekZZYZ0PAl…g8kxTBr81V7k25jWLuZzcHPZHQ.bftVt5kyWJS067Z4ncibRA"}
    3. __proto__: Object

  2. giytanzzha4tgnjs:

    1. conn: {document: "QTEyOEdDTQ.GFC8HqSwajb9jUthihlg2dc5L5gJj7axH4U1O0H…00URxfOPRo2I9jyO5HmrEEKm8Q.KZim6LitfLrAs4VTTWBtLA"}
    2. parent: {document: "QTEyOEdDTQ.p-wIFXp5VELvZx5v1ub82Zrs3yOt24EWpbsy43s…8h1GOrusAo55428capZCxrT3xs.Yvk7mc9jwyNE0DfhHue51A"}
    3. type: {document: "QTEyOEdDTQ.ckW9WiB7ZPC-4dQtE52IBTBAyHmXC6Gxb40MFNL…5FjoWh.AoPxonuHyD4HuDwBsSc.Ni0NIn9tyrkNjlDlzKJ2qg"}
    4. __proto__: Object

  3. giytkojrgu2tcmbw:

    1. currency: {document: "QTEyOEdDTQ.hQz0cCd0ngRDTKs6mqO8qqBnyDJgOvrM792Xs3y…v3SlJSxT1p6aC.m9923cGIFixp.wQ55dmFJyFIhIiQI7LgGhQ"}
    2. invoice: {document: "QTEyOEdDTQ.NCrMDyUyPxAuW_b0gEcF1BxWubdSCXEIdMVmhxt…DZZriJfjT2QdNJbjMpZh3dpguj.IBxdtmoBRUt844rZx-2ttA"}
    3. __proto__: Object

  4. gqzdqojugi4tknbv:

    1. action: {document: "QTEyOEdDTQ.EYSw4Vj-VlIEDvRB6FO3lWAyzk_bmw_97LPI18i…Kjjap6YXne1M4gXbBZ92AbJqBh.ffIV6VcHyLsgCXHQsUZyVw"}
    2. changeset: {document: "QTEyOEdDTQ.Ff44_w87BhuG5viQ2m75GF9vFpkx4Nge4xFUfxw…6F4LgcLXehjmUh7u9yjk1oo6QK.Pak2S9KU8oJBipZk5mDaJg"}
    3. conn: {document: "QTEyOEdDTQ.i7LNqEzjsvqFXlyKZLmWE0Jj-6JHSiJPuQYHCdw…kHWWuSVMYIh7Yr79iuVfwPwayA.8c6o3Ke86NdW1ldEgWoKEw"}
    4. currency_us: {document: "QTEyOEdDTQ.Np39iu7OtdlSepYuQsNqHNgCEXaWukWJZ59_4Mu…3U50h-KYB2yqq.c9H97HU6nQYf.5WWwumklVLAT6GO6sPrJQA"}
    5. invoices: {document: "QTEyOEdDTQ.1MJXW0GvMPZ4w30_-9zAw15UMJTYyqJwi3s7c33…YHQbELwTuFssGlWn0gBrvcK_io.IGOBBM2E2PTNeDfWbAzKTQ"}
    6. parent: {document: "QTEyOEdDTQ.J5hkxodrx40FchLomo7Gmdtvbhzt5nIokzYhTT0…7UZuYxQERun0fAuX7pfaqn6EFw.d0FlWlDgsNLVJgTIXZs2fg"}
    7. po_grantotal: {document: "QTEyOEdDTQ.7pdcRGyALNNERy61CMSA6KUTnlagQOxbSymK-a0…0xlk.ZtVS4b1qlgTPZakD.V2Gt.msowySouBcC2oeeqL8ZbFg"}
    8. __proto__: Object

Thanks again for the help.

1 Like

Can you also do IO.inspect(@changeset) (before form_for) in form.html and show the result of it when you are trying to update the page with poke and it fails?

This is the form.html.drab code:

<% IO.inspect(@action) %>
<% IO.inspect(@changeset) %>
<%= form_for @changeset, @action, fn f -> %>
  <div class="row">
    <div class="col-md-12">
      <%= render "_invoices.html", conn: @conn, invoices: @invoices, parent: @parent %>
    </div>
  </div>

This is the result when I click the drab element to call de poke function:

iex(25)> is the moment when the page first loads
iex(27)> is the moment when the poke function was called

iex(25)> "/contracts/2/payment_orders"
#Ecto.Changeset<
  action: nil,
  changes: %{},
  errors: [
    date: {"can't be blank", [validation: :required]},
    concept: {"can't be blank", [validation: :required]},
    check_number: {"can't be blank", [validation: :required]},
    bank_account_id: {"can't be blank", [validation: :required]}
  ],
  data: #Epr.Payments.PaymentOrder<>,
  valid?: false
>

    Started Drab for __drab:same_path:/contracts/2/payment_orders/new, handling events in EprWeb.PaymentOrderCommander
    You may debug Drab functions in IEx by copy/paste the following:
import Drab.{Modal, Element, Live, Core}
socket = Drab.get_socket(pid("0.2228.0"))

    Examples:
socket |> alert("Title", "Sure?", buttons: [ok: "Azaliż", cancel: "Poniechaj"])
socket |> set_style("body", backgroundColor: "red")
socket |> poke(text: "This assign has been drabbed!")
socket |> exec_js("alert('hello from IEx!')")


nil
iex(26)>
nil
iex(27)> "/contracts/2/payment_orders"
#Ecto.Changeset<
  action: nil,
  changes: %{},
  errors: [
    date: {"can't be blank", [validation: :required]},
    concept: {"can't be blank", [validation: :required]},
    check_number: {"can't be blank", [validation: :required]},
    bank_account_id: {"can't be blank", [validation: :required]}
  ],
  data: #Epr.Payments.PaymentOrder<>,
  valid?: false
>

I have no idea what can be wrong then. All looks good, the data given to form_for looks exactly the same, I have no idea where the nil may come from :frowning:

1 Like

@grych,

So I finally identified the problem. Turns out that I use a Enum function inside the form.html.drab. This is the code:

<%= form_for @changeset, @action, fn f -> %>
  <div class="row">
    <div class="col-md-12">
      <%= render "_invoices.html", conn: @conn, invoices: @invoices, parent: @parent %>
    </div>
  </div>
.......
.......
      <div class="form-group">
        <%= label f, "Cuenta de banco", class: "control-label" %>
        <%= select f,
            :bank_account_id,
            Enum.map(assigns[:bank_accounts], &{&1.num, &1.id} ),
            class: "form-control",
            prompt: "Seleccione un número de cuenta"
         %>
        <%= error_tag f, :bank_account %>
      </div>

Please note that is use assigns[:bank_accounts] instead of @bank_accounts.

The first time this form.html.drab is rendered, this assign is there because I added it in the controller and the form renders correctly with the bank_accounts information:

  def new(conn, _params, %Epr.Debts.Contract{} = document) do
    invoices = Epr.Debts.list_unpaid_invoices(document)

      changeset =
        %PaymentOrder{}
        |> Payments.new_payment_order()

      render(
        conn,
        "new.html",
        changeset: changeset,
        parent: document,
        invoices: invoices,
        bank_accounts: Epr.Payments.list_all_bank_accounts(),
        currency_us: document.currency_us,
        po_grantotal: 0,
        type: "contract"
      )
  end

But when I check the drab assigns, it is not there:

iex(25)> socket |> assigns("form.html")
[:action, :changeset, :conn, :currency_us, :invoices, :parent, :po_grantotal]
iex(26)>

And when you poke the assign and re-render the form, the assign[:bank_accounts] is nil.

So simple solution was to change the assign[:bank_accounts] to @bank_accounts as I should and now it all works fine.

iex(29)> socket |> assigns("form.html")
[:po_grantotal, :conn, :invoices, :parent, :currency_us, :action,
 :bank_accounts, :changeset]

Thanks for your help.

Best regards,

1 Like