Convert reverse search parsing to changeset-backed form

lib/philomena/duplicate_reports.ex

@@ -8,6 +8,8 @@ defmodule Philomena.DuplicateReports do
   alias Philomena.Repo
 
   alias Philomena.DuplicateReports.DuplicateReport
+  alias Philomena.DuplicateReports.SearchQuery
+  alias Philomena.DuplicateReports.Uploader
   alias Philomena.ImageIntensities.ImageIntensity
   alias Philomena.Images.Image
   alias Philomena.Images
@@ -47,6 +49,63 @@ defmodule Philomena.DuplicateReports do
       limit: ^limit
   end
 
+  @doc """
+  Executes the reverse image search query from parameters.
+
+  ## Examples
+
+      iex> execute_search_query(%{"image" => ..., "distance" => "0.25"})
+      {:ok, [%Image{...}, ....]}
+
+      iex> execute_search_query(%{"image" => ..., "distance" => "asdf"})
+      {:error, %Ecto.Changeset{}}
+
+  """
+  def execute_search_query(attrs \\ %{}) do
+    %SearchQuery{}
+    |> SearchQuery.changeset(attrs)
+    |> Uploader.analyze_upload(attrs)
+    |> Ecto.Changeset.apply_action(:create)
+    |> case do
+      {:ok, search_query} ->
+        intensities = generate_intensities(search_query)
+        aspect = search_query.image_aspect_ratio
+        limit = search_query.limit
+        dist = search_query.distance
+
+        images =
+          {intensities, aspect}
+          |> find_duplicates(dist: dist, aspect_dist: dist, limit: limit)
+          |> preload([:user, :intensity, [:sources, tags: :aliases]])
+          |> Repo.all()
+
+        {:ok, images}
+
+      error ->
+        error
+    end
+  end
+
+  defp generate_intensities(search_query) do
+    analysis = SearchQuery.to_analysis(search_query)
+    file = search_query.uploaded_image
+
+    PhilomenaMedia.Processors.intensities(analysis, file)
+  end
+
+  @doc """
+  Returns an `%Ecto.Changeset{}` for tracking search query changes.
+
+  ## Examples
+
+      iex> change_search_query(search_query)
+      %Ecto.Changeset{source: %SearchQuery{}}
+
+  """
+  def change_search_query(%SearchQuery{} = search_query) do
+    SearchQuery.changeset(search_query)
+  end
+
   @doc """
   Gets a single duplicate_report.
 

lib/philomena/duplicate_reports/search_query.ex

@@ -0,0 +1,59 @@
+defmodule Philomena.DuplicateReports.SearchQuery do
+  use Ecto.Schema
+  import Ecto.Changeset
+
+  embedded_schema do
+    field :distance, :float, default: 0.25
+    field :limit, :integer, default: 10
+
+    field :image_width, :integer
+    field :image_height, :integer
+    field :image_format, :string
+    field :image_duration, :float
+    field :image_mime_type, :string
+    field :image_is_animated, :boolean
+    field :image_aspect_ratio, :float
+    field :uploaded_image, :string, virtual: true
+  end
+
+  @doc false
+  def changeset(search_query, attrs \\ %{}) do
+    search_query
+    |> cast(attrs, [:distance, :limit])
+    |> validate_number(:distance, greater_than_or_equal_to: 0, less_than_or_equal_to: 1)
+    |> validate_number(:limit, greater_than_or_equal_to: 1, less_than_or_equal_to: 50)
+  end
+
+  @doc false
+  def image_changeset(search_query, attrs \\ %{}) do
+    search_query
+    |> cast(attrs, [
+      :image_width,
+      :image_height,
+      :image_format,
+      :image_duration,
+      :image_mime_type,
+      :image_is_animated,
+      :image_aspect_ratio,
+      :uploaded_image
+    ])
+    |> validate_number(:image_width, greater_than: 0)
+    |> validate_number(:image_height, greater_than: 0)
+    |> validate_inclusion(
+      :image_mime_type,
+      ~W(image/gif image/jpeg image/png image/svg+xml video/webm),
+      message: "(#{attrs["image_mime_type"]}) is invalid"
+    )
+  end
+
+  @doc false
+  def to_analysis(search_query) do
+    %PhilomenaMedia.Analyzers.Result{
+      animated?: search_query.image_is_animated,
+      dimensions: {search_query.image_width, search_query.image_height},
+      duration: search_query.image_duration,
+      extension: search_query.image_format,
+      mime_type: search_query.image_mime_type
+    }
+  end
+end

lib/philomena/duplicate_reports/uploader.ex

@@ -0,0 +1,17 @@
+defmodule Philomena.DuplicateReports.Uploader do
+  @moduledoc """
+  Upload and processing callback logic for SearchQuery images.
+  """
+
+  alias Philomena.DuplicateReports.SearchQuery
+  alias PhilomenaMedia.Uploader
+
+  def analyze_upload(search_query, params) do
+    Uploader.analyze_upload(
+      search_query,
+      "image",
+      params["image"],
+      &SearchQuery.image_changeset/2
+    )
+  end
+end

lib/philomena_web/controllers/api/json/search/reverse_controller.ex

@@ -1,7 +1,7 @@
 defmodule PhilomenaWeb.Api.Json.Search.ReverseController do
   use PhilomenaWeb, :controller
 
-  alias PhilomenaWeb.ImageReverse
+  alias Philomena.DuplicateReports
   alias Philomena.Interactions
 
   plug PhilomenaWeb.ScraperCachePlug
@@ -14,7 +14,14 @@ defmodule PhilomenaWeb.Api.Json.Search.ReverseController do
       image_params
       |> Map.put("distance", conn.params["distance"])
       |> Map.put("limit", conn.params["limit"])
-      |> ImageReverse.images()
+      |> DuplicateReports.execute_search_query()
+      |> case do
+        {:ok, images} ->
+          images
+
+        {:error, _changeset} ->
+          []
+      end
 
     interactions = Interactions.user_interactions(images, user)
 

lib/philomena_web/controllers/search/reverse_controller.ex

@@ -1,7 +1,8 @@
 defmodule PhilomenaWeb.Search.ReverseController do
   use PhilomenaWeb, :controller
 
-  alias PhilomenaWeb.ImageReverse
+  alias Philomena.DuplicateReports.SearchQuery
+  alias Philomena.DuplicateReports
 
   plug PhilomenaWeb.ScraperCachePlug
   plug PhilomenaWeb.ScraperPlug, params_key: "image", params_name: "image"
@@ -12,12 +13,18 @@ defmodule PhilomenaWeb.Search.ReverseController do
 
   def create(conn, %{"image" => image_params})
       when is_map(image_params) and image_params != %{} do
-    images = ImageReverse.images(image_params)
+    case DuplicateReports.execute_search_query(image_params) do
+      {:ok, images} ->
+        changeset = DuplicateReports.change_search_query(%SearchQuery{})
+        render(conn, "index.html", title: "Reverse Search", images: images, changeset: changeset)
 
-    render(conn, "index.html", title: "Reverse Search", images: images)
+      {:error, changeset} ->
+        render(conn, "index.html", title: "Reverse Search", images: nil, changeset: changeset)
+    end
   end
 
   def create(conn, _params) do
-    render(conn, "index.html", title: "Reverse Search", images: nil)
+    changeset = DuplicateReports.change_search_query(%SearchQuery{})
+    render(conn, "index.html", title: "Reverse Search", images: nil, changeset: changeset)
   end
 end

lib/philomena_web/image_reverse.ex

@@ -1,74 +0,0 @@
-defmodule PhilomenaWeb.ImageReverse do
-  alias PhilomenaMedia.Analyzers
-  alias PhilomenaMedia.Processors
-  alias Philomena.DuplicateReports
-  alias Philomena.Repo
-  import Ecto.Query
-
-  def images(image_params) do
-    image_params
-    |> Map.get("image")
-    |> analyze()
-    |> intensities()
-    |> case do
-      :error ->
-        []
-
-      {analysis, intensities} ->
-        {width, height} = analysis.dimensions
-        aspect = width / height
-        dist = parse_dist(image_params)
-        limit = parse_limit(image_params)
-
-        {intensities, aspect}
-        |> DuplicateReports.find_duplicates(dist: dist, aspect_dist: dist, limit: limit)
-        |> preload([:user, :intensity, [:sources, tags: :aliases]])
-        |> Repo.all()
-    end
-  end
-
-  defp analyze(%Plug.Upload{path: path}) do
-    case Analyzers.analyze(path) do
-      {:ok, analysis} -> {analysis, path}
-      _ -> :error
-    end
-  end
-
-  defp analyze(_upload), do: :error
-
-  defp intensities(:error), do: :error
-
-  defp intensities({analysis, path}) do
-    {analysis, Processors.intensities(analysis, path)}
-  end
-
-  # The distance metric is taxicab distance, not Euclidean,
-  # because this is more efficient to index.
-  defp parse_dist(%{"distance" => distance}) do
-    distance
-    |> Decimal.parse()
-    |> case do
-      {value, _rest} -> Decimal.to_float(value)
-      _ -> 0.25
-    end
-    |> clamp(0.01, 1.0)
-  end
-
-  defp parse_dist(_params), do: 0.25
-
-  defp parse_limit(%{"limit" => limit}) do
-    limit
-    |> Integer.parse()
-    |> case do
-      {limit, _rest} -> limit
-      _ -> 10
-    end
-    |> clamp(1, 50)
-  end
-
-  defp parse_limit(_params), do: 10
-
-  defp clamp(n, min, _max) when n < min, do: min
-  defp clamp(n, _min, max) when n > max, do: max
-  defp clamp(n, _min, _max), do: n
-end

lib/philomena_web/templates/search/reverse/index.html.slime

@@ -1,6 +1,6 @@
 h1 Reverse Search
 
-= form_for :image, ~p"/search/reverse", [multipart: true], fn f ->
+= form_for @changeset, ~p"/search/reverse", [multipart: true, as: :image], fn f ->
   p
     ' Basic image similarity search. Finds uploaded images similar to the one
     ' provided based on simple intensities and uses the median frame of
@@ -13,6 +13,10 @@ h1 Reverse Search
     p Upload a file from your computer, or provide a link to the page containing the image and click Fetch.
     .field
       = file_input f, :image, class: "input js-scraper"
+      = error_tag f, :image
+      = error_tag f, :image_width
+      = error_tag f, :image_height
+      = error_tag f, :image_mime_type
 
     .field.field--inline
       = url_input f, :url, name: "url", class: "input input--wide js-scraper", placeholder: "Link a deviantART page, a Tumblr post, or the image directly"
@@ -26,9 +30,10 @@ h1 Reverse Search
   .field
     = label f, :distance, "Match distance (suggested values: between 0.2 and 0.5)"
     br
-    = number_input f, :distance, value: 0.25, min: 0, max: 1, step: 0.01, class: "input"
+    = number_input f, :distance, min: 0, max: 1, step: 0.01, class: "input"
+    = error_tag f, :distance
 
-  = hidden_input f, :limit, value: 10
+  = error_tag f, :limit
 
   .field
     = submit "Reverse Search", class: "button"