Add OGMate (#53)

Replace OG image implementation with OGMate

Author: joladev

lib/jola_dev/og_image.ex

@@ -2,49 +2,21 @@ defmodule JolaDev.OGImage do
   @moduledoc """
   Per-page Open Graph image lookup. All content from
   `JolaDev.OGImage.Catalog` is rendered at compile time via
-  `JolaDev.OGImage.Renderer` and baked into the `@images` module
-  attribute, then served at runtime from `JolaDevWeb.Plugs.OGImage`.
+  `OGMate`, then served at runtime from `JolaDevWeb.Plugs.OGImage`.
   """
 
   alias JolaDev.OGImage.Catalog
   alias JolaDev.OGImage.Renderer
 
-  @dev_mode Application.compile_env!(:jola_dev, :og_image_dev_mode)
-  @images if not @dev_mode,
-            do:
-              Map.new(Catalog.all_slugs(), fn slug ->
-                {title, description} = Catalog.content_for(slug)
-                {slug, Renderer.generate_bytes(title, description)}
-              end)
+  # credo:disable-for-next-line Credo.Check.Readability.StrictModuleLayout
+  use OGMate,
+    all_keys: Catalog.all_slugs(),
+    content_for: Catalog,
+    renderer: Renderer,
+    default: Catalog.content_for("home"),
+    dev_mode: Application.compile_env!(:jola_dev, :og_image_dev_mode)
 
-  @default_image (
-                   {title, description} = Catalog.content_for("home")
-                   Renderer.generate_bytes(title, description)
-                 )
-
-  @doc """
-  Returns the public asset path for a slug's OG image. Used so the
-  path scheme stays consistent.
-  """
-  def path_for(slug) when is_binary(slug), do: "/images/og/#{slug}.png"
-
-  def image_for(slug) do
-    with :error <- image_for_slug(slug) do
-      {:ok, @default_image}
-    end
-  end
-
-  def default_image do
-    @default_image
-  end
-
-  defp image_for_slug(slug) do
-    if @images do
-      Map.fetch(@images, slug)
-    else
-      with {title, description} <- Catalog.content_for(slug) do
-        {:ok, Renderer.generate_bytes(title, description)}
-      end
-    end
+  def path_for(slug) do
+    "/images/og/#{slug}.png"
   end
 end

lib/jola_dev/og_image/renderer.ex

@@ -21,10 +21,13 @@ defmodule JolaDev.OGImage.Renderer do
 
   @logo_path "priv/static/images/logo.png"
 
-  def generate_bytes(title, description) when is_binary(title) and is_binary(description) do
-    title
-    |> build_canvas(description)
-    |> Image.write!(:memory, suffix: ".png")
+  def render(title, description) when is_binary(title) and is_binary(description) do
+    image =
+      title
+      |> build_canvas(description)
+      |> Image.write!(:memory, suffix: ".png")
+
+    {:ok, image}
   end
 
   defp build_canvas(title, description) do

mix.exs

@@ -73,7 +73,8 @@ defmodule JolaDev.MixProject do
       {:tidewave, "~> 0.5", only: :dev},
       {:credo, "~> 1.7", only: [:dev, :test], runtime: false},
       {:image, "~> 0.67"},
-      {:logger_json, "~> 7.0"}
+      {:logger_json, "~> 7.0"},
+      {:og_mate, "~> 0.1"}
     ]
   end
 

mix.lock

@@ -30,6 +30,7 @@
   "nimble_parsec": {:hex, :nimble_parsec, "1.4.2", "8efba0122db06df95bfaa78f791344a89352ba04baedd3849593bfce4d0dc1c6", [:mix], [], "hexpm", "4b21398942dda052b403bbe1da991ccd03a053668d147d53fb8c4e0efe09c973"},
   "nimble_pool": {:hex, :nimble_pool, "1.1.0", "bf9c29fbdcba3564a8b800d1eeb5a3c58f36e1e11d7b7fb2e084a643f645f06b", [:mix], [], "hexpm", "af2e4e6b34197db81f7aad230c1118eac993acc0dae6bc83bac0126d4ae0813a"},
   "nimble_publisher": {:hex, :nimble_publisher, "1.1.1", "3ea4d4cfca45b11a5377bce7608367a9ddd7e717a9098161d8439eca23e239aa", [:mix], [{:earmark, "~> 1.4", [hex: :earmark, repo: "hexpm", optional: false]}, {:makeup, "~> 1.0", [hex: :makeup, repo: "hexpm", optional: false]}], "hexpm", "d67e15bddf07e8c60f75849008b78ea8c6b2b4ae8e3f882ccf0a22d57bd42ed0"},
+  "og_mate": {:hex, :og_mate, "0.1.0", "b2aa3baeb379fc2ea3c9872031b2b19fd127493d3c9e374ffeb3062343f11db4", [:mix], [{:image, "~> 0.67.0", [hex: :image, repo: "hexpm", optional: false]}, {:nimble_options, "~> 1.1", [hex: :nimble_options, repo: "hexpm", optional: false]}], "hexpm", "80f7aeac521177e0e5ff253de15d6ee263fbc0124a8c36568fc3abd1762d0c49"},
   "phoenix": {:hex, :phoenix, "1.8.7", "d8d755b4ff4b449f610223dd706b4ae64155cb720d3dc09c706c079ecea189e4", [:mix], [{:bandit, "~> 1.0", [hex: :bandit, repo: "hexpm", optional: true]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: true]}, {:phoenix_pubsub, "~> 2.1", [hex: :phoenix_pubsub, repo: "hexpm", optional: false]}, {:phoenix_template, "~> 1.0", [hex: :phoenix_template, repo: "hexpm", optional: false]}, {:phoenix_view, "~> 2.0", [hex: :phoenix_view, repo: "hexpm", optional: true]}, {:plug, "~> 1.14", [hex: :plug, repo: "hexpm", optional: false]}, {:plug_cowboy, "~> 2.7", [hex: :plug_cowboy, repo: "hexpm", optional: true]}, {:plug_crypto, "~> 1.2 or ~> 2.0", [hex: :plug_crypto, repo: "hexpm", optional: false]}, {:telemetry, "~> 0.4 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}, {:websock_adapter, "~> 0.5.3", [hex: :websock_adapter, repo: "hexpm", optional: false]}], "hexpm", "47352f72d6ab31009ef77516b1b3a14745be97b54061fd458031b9d8294869d5"},
   "phoenix_html": {:hex, :phoenix_html, "4.3.0", "d3577a5df4b6954cd7890c84d955c470b5310bb49647f0a114a6eeecc850f7ad", [:mix], [], "hexpm", "3eaa290a78bab0f075f791a46a981bbe769d94bc776869f4f3063a14f30497ad"},
   "phoenix_live_dashboard": {:hex, :phoenix_live_dashboard, "0.8.7", "405880012cb4b706f26dd1c6349125bfc903fb9e44d1ea668adaf4e04d4884b7", [:mix], [{:ecto, "~> 3.6.2 or ~> 3.7", [hex: :ecto, repo: "hexpm", optional: true]}, {:ecto_mysql_extras, "~> 0.5", [hex: :ecto_mysql_extras, repo: "hexpm", optional: true]}, {:ecto_psql_extras, "~> 0.7", [hex: :ecto_psql_extras, repo: "hexpm", optional: true]}, {:ecto_sqlite3_extras, "~> 1.1.7 or ~> 1.2.0", [hex: :ecto_sqlite3_extras, repo: "hexpm", optional: true]}, {:mime, "~> 1.6 or ~> 2.0", [hex: :mime, repo: "hexpm", optional: false]}, {:phoenix_live_view, "~> 0.19 or ~> 1.0", [hex: :phoenix_live_view, repo: "hexpm", optional: false]}, {:telemetry_metrics, "~> 0.6 or ~> 1.0", [hex: :telemetry_metrics, repo: "hexpm", optional: false]}], "hexpm", "3a8625cab39ec261d48a13b7468dc619c0ede099601b084e343968309bd4d7d7"},

test/jola_dev/og_image/renderer_test.exs

@@ -4,9 +4,9 @@ defmodule JolaDev.OGImage.RendererTest do
 
   describe "generate_bytes/2" do
     test "returns a PNG binary" do
-      bytes = Renderer.generate_bytes("Title", "Description.")
+      bytes = Renderer.render("Title", "Description.")
 
-      assert <<137, "PNG\r\n", 26, "\n", _rest::binary>> = bytes
+      assert {:ok, <<137, "PNG\r\n", 26, "\n", _rest::binary>>} = bytes
     end
   end
 end