Let's Build An Instagram Clone With The PETAL(Phoenix, Elixir, TailwindCSS, AlpineJS, LiveView) Stack [PART 7]
Tags: elixir, webdev, programming, tutorial
Published: 2021-05-20 20:37:27

In [part 6](https://elixirprogrammer.com/learn/lets-build-an-instagram-clone-with-the-petal-phoenix-elixir-tailwindcss-alpinejs-liveview-stack-part-6) we added the homepage, in this part, we will work on the search functionality in our top header navigation menu. You can catch up with the [Instagram Clone GitHub Repo](https://github.com/elixirprogrammer/InstagramClonePETAL).

The search functionality will give the ability to search users by username or full name, we will only need a map with the avatar URL, username, and full name, let's add a function to get that in our accounts context. Inside `lib/instagram_clone/accounts.ex`:

```elixir

...

  def search_users(q) do
    User
    |> where([u], ilike(u.username, ^"%#{q}%"))
    |> or_where([u], ilike(u.full_name, ^"%#{q}%"))
    |> select([u], map(u, [:avatar_url, :username, :full_name]))
    |> Repo.all()
  end

...

```

We will be handling the event to search inside our header nav component, open `lib/instagram_clone_web/templates/layout/live.html.leex`, and let's send an ID to our component to be able to handle the event:

```html
<%= if @current_user do %>
  <%= live_component @socket, InstagramCloneWeb.HeaderNavComponent, id: 1, current_user: @current_user %>

<% else %>
  <%= if @live_action !== :root_path do %>
    <%= live_component @socket, InstagramCloneWeb.HeaderNavComponent, id: 1, current_user: @current_user %>
  <% end %>
<% end %>

<main role="main" class="container mx-auto max-w-full md:w-11/12 2xl:w-6/12 pt-24">
  <p class="alert alert-info" role="alert"
    phx-click="lv:clear-flash"
    phx-value-key="info"><%= live_flash(@flash, :info) %></p>

  <p class="alert alert-danger" role="alert"
    phx-click="lv:clear-flash"
    phx-value-key="error"><%= live_flash(@flash, :error) %></p>

  <%= @inner_content %>
</main>
```

Inside `lib/instagram_clone_web/live/header_nav_component.html.leex` let's use AlpineJs to open the UL where we are going to display the results when the input has at least one letter, if nothing is inside or click away the input, nothing will be displayed. Let's use the `phx-change` form events to run our search, also we will assign to our socket a `@overflow_y_scroll_ul` to display the scrollbar when results are greater than 6.

```html
    <div x-data="{open: false, inputText: null}" class="w-2/5 flex justify-end relative">
      <form id="search-users-form" phx-change="search_users" phx-target="<%= @myself %>">
        <input
          phx-debounce="800"
          x-model="inputText"
          x-on:input="[(inputText.length != 0) ? open = true : open = false]"
          name="q"
          type="search"
          placeholder="Search"
          autocomplete="off"
          class="h-7 bg-gray-50 shadow-sm border-gray-300 focus:ring-gray-300 focus:ring-opacity-50 focus:border-gray-400  px-0.5 rounded-sm">
      </form>

      <ul
      x-show="open"
      @click.away="open = false"
      class="<%= @overflow_y_scroll_ul %> absolute top-10 -right-24 w-96 shadow-md h-96 bg-gray-50">

      </ul>
    </div>
```

Inside the UL that we will be displaying our search results we will need 3 assigns, `@searched_users` that will be the results which we are going to loop through, `@while_searching_users?` that will be a boolean to determine when to display a loading indicator in the case that the connection is slow or takes a while, for user interface friendly feedback, `@users_not_found?` another boolean to display a no results found message.

```html

      <ul
      x-show="open"
      @click.away="open = false"
      class="<%= @overflow_y_scroll_ul %> absolute top-10 -right-24 w-96 shadow-md h-96 bg-gray-50">

        <%= for user <- @searched_users do %>
          <%= live_redirect to: Routes.user_profile_path(@socket, :index, user.username) do %>
            <li class="flex items-center px-4 py-3 hover:bg-gray-100">
              <%= img_tag Avatar.get_thumb(user.avatar_url), class: "w-10 h-10 rounded-full object-cover object-center" %>
              <div class="ml-3">
                <h2 class="truncate font-bold text-sm text-gray-500"><%= user.username %></h2>
                <h3 class="truncate text-sm text-gray-500"><%= user.full_name %></h3>
              </div>
            </li>
          <% end %>
        <% end %>

        <%= if @while_searching_users? do %>
          <li class="flex justify-center items-center h-full">
            <svg class="animate-spin -ml-1 mr-3 h-5 w-5 text-gray-300" xmlns="http://www.w3.org/2000/svg" fill="none" viewBox="0 0 24 24">
            <circle class="opacity-25" cx="12" cy="12" r="10" stroke="currentColor" stroke-width="4"></circle>
            <path class="opacity-75" fill="currentColor" d="M4 12a8 8 0 018-8V0C5.373 0 0 5.373 0 12h4zm2 5.291A7.962 7.962 0 014 12H0c0 3.042 1.135 5.824 3 7.938l3-2.647z"></path>
          </svg>
          </li>
        <% end %>

        <%= if @users_not_found? do %>
          <li class="text-sm text-gray-400 flex justify-center items-center h-full">No results found.</li>
        <% end %>
      </ul>
      
```

Our updated `lib/instagram_clone_web/live/header_nav_component.html.leex` should look like the following:

```html
<div class="h-14 border-b-2 flex fixed w-full bg-white z-40">
  <header class="flex items-center container mx-auto max-w-full md:w-11/12 2xl:w-6/12">
    <%= live_redirect to: Routes.page_path(@socket, :index) do %>
      <h1 class="text-2xl font-bold italic">#InstagramClone</h1>
    <% end %>
    <div x-data="{open: false, inputText: null}" class="w-2/5 flex justify-end relative">
      <form id="search-users-form" phx-change="search_users" phx-target="<%= @myself %>">
        <input
          phx-debounce="800"
          x-model="inputText"
          x-on:input="[(inputText.length != 0) ? open = true : open = false]"
          name="q"
          type="search"
          placeholder="Search"
          autocomplete="off"
          class="h-7 bg-gray-50 shadow-sm border-gray-300 focus:ring-gray-300 focus:ring-opacity-50 focus:border-gray-400  px-0.5 rounded-sm">
      </form>

      <ul
      x-show="open"
      @click.away="open = false"
      class="<%= @overflow_y_scroll_ul %> absolute top-10 -right-24 w-96 shadow-md h-96 bg-gray-50">

        <%= for user <- @searched_users do %>
          <%= live_redirect to: Routes.user_profile_path(@socket, :index, user.username) do %>
            <li class="flex items-center px-4 py-3 hover:bg-gray-100">
              <%= img_tag Avatar.get_thumb(user.avatar_url), class: "w-10 h-10 rounded-full object-cover object-center" %>
              <div class="ml-3">
                <h2 class="truncate font-bold text-sm text-gray-500"><%= user.username %></h2>
                <h3 class="truncate text-sm text-gray-500"><%= user.full_name %></h3>
              </div>
            </li>
          <% end %>
        <% end %>

        <%= if @while_searching_users? do %>
          <li class="flex justify-center items-center h-full">
            <svg class="animate-spin -ml-1 mr-3 h-5 w-5 text-gray-300" xmlns="http://www.w3.org/2000/svg" fill="none" viewBox="0 0 24 24">
            <circle class="opacity-25" cx="12" cy="12" r="10" stroke="currentColor" stroke-width="4"></circle>
            <path class="opacity-75" fill="currentColor" d="M4 12a8 8 0 018-8V0C5.373 0 0 5.373 0 12h4zm2 5.291A7.962 7.962 0 014 12H0c0 3.042 1.135 5.824 3 7.938l3-2.647z"></path>
          </svg>
          </li>
        <% end %>

        <%= if @users_not_found? do %>
          <li class="text-sm text-gray-400 flex justify-center items-center h-full">No results found.</li>
        <% end %>
      </ul>
    </div>
    <nav class="w-3/5 relative">
      <ul x-data="{open: false}" class="flex justify-end">
        <%= if @current_user do %>
          <li class="w-7 h-7 text-gray-600">
            <%= live_redirect to: Routes.page_path(@socket, :index) do %>
              <svg xmlns="http://www.w3.org/2000/svg" fill="none" viewBox="0 0 24 24" stroke="currentColor">
                <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M3 12l2-2m0 0l7-7 7 7M5 10v10a1 1 0 001 1h3m10-11l2 2m-2-2v10a1 1 0 01-1 1h-3m-6 0a1 1 0 001-1v-4a1 1 0 011-1h2a1 1 0 011 1v4a1 1 0 001 1m-6 0h6" />
              </svg>
            <% end %>
          </li>
          <li class="w-7 h-7 ml-6 text-gray-600">
            <%= live_redirect to: Routes.live_path(@socket, InstagramCloneWeb.PostLive.New) do %>
              <svg xmlns="http://www.w3.org/2000/svg" fill="none" viewBox="0 0 24 24" stroke="currentColor">
                <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M12 9v3m0 0v3m0-3h3m-3 0H9m12 0a9 9 0 11-18 0 9 9 0 0118 0z" />
              </svg>
            <% end %>
          </li>
          <li class="w-7 h-7 ml-6 text-gray-600">
            <svg xmlns="http://www.w3.org/2000/svg" fill="none" viewBox="0 0 24 24" stroke="currentColor">
              <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M8 12h.01M12 12h.01M16 12h.01M21 12c0 4.418-4.03 8-9 8a9.863 9.863 0 01-4.255-.949L3 20l1.395-3.72C3.512 15.042 3 13.574 3 12c0-4.418 4.03-8 9-8s9 3.582 9 8z" />
            </svg>
          </li>
          <li class="w-7 h-7 ml-6 text-gray-600">
            <svg xmlns="http://www.w3.org/2000/svg" fill="none" viewBox="0 0 24 24" stroke="currentColor">
              <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M21 12a9 9 0 01-9 9m9-9a9 9 0 00-9-9m9 9H3m9 9a9 9 0 01-9-9m9 9c1.657 0 3-4.03 3-9s-1.343-9-3-9m0 18c-1.657 0-3-4.03-3-9s1.343-9 3-9m-9 9a9 9 0 019-9" />
            </svg>
          </li>
          <li class="w-7 h-7 ml-6 text-gray-600">
            <svg xmlns="http://www.w3.org/2000/svg" fill="none" viewBox="0 0 24 24" stroke="currentColor">
              <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M4.318 6.318a4.5 4.5 0 000 6.364L12 20.364l7.682-7.682a4.5 4.5 0 00-6.364-6.364L12 7.636l-1.318-1.318a4.5 4.5 0 00-6.364 0z" />
            </svg>
          </li>
          <li
            @click="open = true"
            class="w-7 h-7 ml-6 shadow-md rounded-full overflow-hidden cursor-pointer"
          >
            <%= img_tag InstagramClone.Uploaders.Avatar.get_thumb(@current_user.avatar_url),
            class: "w-full h-full object-cover object-center" %>
          </li>
          <ul class="absolute top-14 w-56 bg-white shadow-md text-sm -right-8"
              x-show="open"
              @click.away="open = false"
              x-transition:enter="transition ease-out duration-200"
              x-transition:enter-start="opacity-0 transform scale-90"
              x-transition:enter-end="opacity-100 transform scale-100"
              x-transition:leave="transition ease-in duration-200"
              x-transition:leave-start="opacity-100 transform scale-100"
              x-transition:leave-end="opacity-0 transform scale-90"
            >
              <%= live_redirect to: Routes.user_profile_path(@socket, :index, @current_user.username) do %>
                <li class="py-2 px-4 hover:bg-gray-50">Profile</li>
              <% end %>
              <li class="py-2 px-4 hover:bg-gray-50">Saved</li>
              <%= live_redirect to: Routes.live_path(@socket, InstagramCloneWeb.UserLive.Settings) do %>
                <li class="py-2 px-4 hover:bg-gray-50">Settings</li>
              <% end %>
              <%= link to: Routes.user_session_path(@socket, :delete), method: :delete do %>
                <li class="border-t-2 py-2 px-4 hover:bg-gray-50">Log Out</li>
              <% end %>
            </ul>
        <% else %>
          <li>
            <%= link "Log In", to: Routes.user_session_path(@socket, :new), class: "w-24 py-1 px-3 border-none shadow rounded text-gray-50 hover:bg-light-blue-600 bg-light-blue-500 font-semibold" %>
          </li>
          <li>
            <%= link "Sign Up", to: Routes.user_registration_path(@socket, :new), class: "w-24 py-1 px-3 border-none text-light-blue-500 hover:text-light-blue-600 font-semibold" %>
          </li>
        <% end %>
      </ul>
    </nav>
  </header>
</div>
```

Inside `lib/instagram_clone_web/live/header_nav_component.ex`:

```elixir
defmodule InstagramCloneWeb.HeaderNavComponent do
  use InstagramCloneWeb, :live_component

  alias InstagramClone.Uploaders.Avatar

  @impl true
  def mount(socket) do
    {:ok,
      socket
      |> assign(while_searching_users?: false)
      |> assign(users_not_found?: false)
      |> assign(overflow_y_scroll_ul: "")
      |> assign(searched_users: [])}
  end

  @impl true
  def handle_event("search_users", %{"q" => search}, socket) do
    if search == "" do
      {:noreply, socket}
    else
      send(self(), {__MODULE__, :search_users_event, search})

      {:noreply,
        socket
        |> assign(users_not_found?: false)
        |> assign(searched_users: [])
        |> assign(overflow_y_scroll_ul: "")
        |> assign(while_searching_users?: true)}
    end
  end

end
```

In our handle event function, first, we are checking if our param is an empty string, nothing will happen. When the param is not empty first we will send a message with the search param to run the search in our parent LiveView, that way we can display the loading indicator while searching, we have to reset our assigns every time that the form is changed and make `while_searching_users?` boolean true to display the loading indicator while searching.

We have to send the message because if we try to do it in our header nav component socket, the assigns happen at the same time first, so if we do that we will not be able to display the loading indicator while searching, and inside a component, we cannot `handle_info` messages it has to be sent to the parent and update the assigns in our parent back to the component. 

The header navigation component is used on every page, so instead of handling the message on each LiveView, let's just do it once for every LiveView, inside `lib/instagram_clone_web.ex` on line 45, inside the `live_view()` function, add the following:

```elixir

...

  def live_view do
    quote do
      use Phoenix.LiveView,
        layout: {InstagramCloneWeb.LayoutView, "live.html"}

      unquote(view_helpers())
      import InstagramCloneWeb.LiveHelpers

      alias InstagramClone.Accounts.User
      alias InstagramClone.Accounts
      
      @impl true
      def handle_info(%{event: "logout_user", payload: %{user: %User{id: id}}}, socket) do
        with %User{id: ^id} <- socket.assigns.current_user do
          {:noreply,
            socket
            |> redirect(to: "/")
            |> put_flash(:info, "Logged out successfully.")}
        else
          _any -> {:noreply, socket}
        end
      end

      @impl true
      def handle_info({InstagramCloneWeb.HeaderNavComponent, :search_users_event, search}, socket) do
        case Accounts.search_users(search) do
          [] ->
            send_update(InstagramCloneWeb.HeaderNavComponent,
              id: 1,
              searched_users: [],
              users_not_found?: true,
              while_searching_users?: false
            )

            {:noreply, socket}

          users ->
            send_update(InstagramCloneWeb.HeaderNavComponent,
              id: 1,
              searched_users: users,
              users_not_found?: false,
              while_searching_users?: false,
              overflow_y_scroll_ul: check_search_result(users)
            )

            {:noreply, socket}
        end
      end

      defp check_search_result(users) do
        if length(users) > 6, do: "overflow-y-scroll", else: ""
      end
    end
  end

...

```
 
We create a case with the function that we added in our accounts context, we [`send_update/3`](https://hexdocs.pm/phoenix_live_view/Phoenix.LiveView.html#send_update/3) to our header nav component, setting `while_searching_users?`  to false on each case to not display the loading indicator because the search is done.

That's it, now you have a fully functional search input, a lot to be done, a lot of features that can be added, but we have come a long way, and we have a big app that we can be proud of, until next time.

I really appreciate your time, thank you so much for reading.

&nbsp;

### CHECKOUT THE [INSTAGRAM CLONE GITHUB REPO](https://github.com/elixirprogrammer/InstagramClonePETAL)

&nbsp;
&nbsp;
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