Add Bluesky scraper (#290)

* add bluesky scraper

* use com.atproto.sync.getBlob to get original bluesky image

* ignore data after bluesky post id

* fix json access and missing function

* fix bluesky fullsize image regex

lib/philomena_proxy/scrapers.ex

@@ -21,6 +21,7 @@ defmodule PhilomenaProxy.Scrapers do
         }
 
   @scrapers [
+    PhilomenaProxy.Scrapers.Bluesky,
     PhilomenaProxy.Scrapers.Deviantart,
     PhilomenaProxy.Scrapers.Pillowfort,
     PhilomenaProxy.Scrapers.Twitter,

lib/philomena_proxy/scrapers/bluesky.ex

@@ -0,0 +1,42 @@
+defmodule PhilomenaProxy.Scrapers.Bluesky do
+  @moduledoc false
+
+  alias PhilomenaProxy.Scrapers.Scraper
+  alias PhilomenaProxy.Scrapers
+
+  @behaviour Scraper
+
+  @url_regex ~r|https://bsky\.app/profile/([^/]+)/post/([^/?#]+)|
+  @fullsize_image_regex ~r|.*/img/feed_fullsize/plain/([^/]+)/([^@]+).*|
+  @blob_image_url_pattern "https://bsky.social/xrpc/com.atproto.sync.getBlob/?did=\\1&cid=\\2"
+
+  @spec can_handle?(URI.t(), String.t()) :: boolean()
+  def can_handle?(_uri, url) do
+    String.match?(url, @url_regex)
+  end
+
+  @spec scrape(URI.t(), Scrapers.url()) :: Scrapers.scrape_result()
+  def scrape(_uri, url) do
+    [handle, id] = Regex.run(@url_regex, url, capture: :all_but_first)
+
+    api_url_resolve_handle = "https://public.api.bsky.app/xrpc/com.atproto.identity.resolveHandle?handle=#{handle}"
+    did = PhilomenaProxy.Http.get(api_url_resolve_handle) |> json!() |> Map.fetch!(:did)
+
+    api_url_get_posts = "https://public.api.bsky.app/xrpc/app.bsky.feed.getPosts?uris=at://#{did}/app.bsky.feed.post/#{id}"
+    post_json = PhilomenaProxy.Http.get(api_url_get_posts) |> json!() |> Map.fetch!(:posts) |> hd
+
+    %{
+      source_url: url,
+      author_name: post_json["author"]["handle"],
+      description: post_json["record"]["text"],
+      images: post_json["embed"]["images"] |> Enum.map(
+        &%{
+          url: String.replace(&1["fullsize"], @fullsize_image_regex, @blob_image_url_pattern),
+          camo_url: PhilomenaProxy.Camo.image_url(&1["thumb"])
+        }
+      )
+    }
+  end
+
+  defp json!({:ok, %{body: body, status: 200}}), do: Jason.decode!(body)
+end