tumblr: fix exception when fetching data for video urls.

Fix an exception when trying to fetch source data for URLs like
https://va.media.tumblr.com/tumblr_pgohk0TjhS1u7mrsl.mp4.

For these URLs it's not possible to use the trick where we try to open
the URL as a HTML page and scrape the post id from the HTML. Instead we
get the raw video if we try to to this.

app/logical/source/extractor/tumblr.rb

@@ -101,13 +101,16 @@ class Source::Extractor
     end
 
     def post_url_from_image_html
+      return nil unless parsed_url.image_url? && parsed_url.file_ext&.in?(%w[jpg png pnj gif])
+
       extracted = image_url_html(parsed_url)&.at("[href*='/post/']")&.[](:href)
       Source::URL.parse(extracted)
     end
+    memoize :post_url_from_image_html
 
     def image_url_html(image_url)
       resp = http.cache(1.minute).headers(accept: "text/html").get(image_url)
-      return nil if resp.code != 200
+      return nil if resp.code != 200 || resp.mime_type != "text/html"
       resp.parse
     end
 

app/logical/source/url/tumblr.rb

@@ -24,6 +24,7 @@ class Source::URL::Tumblr < Source::URL
     # https://68.media.tumblr.com/ee02048f5578595badc95905e17154b4/tumblr_inline_ofbr4452601sk4jd9_250.gif
     # https://media.tumblr.com/ee02048f5578595badc95905e17154b4/tumblr_inline_ofbr4452601sk4jd9_500.gif
     # https://66.media.tumblr.com/b9395771b2d0435fe4efee926a5a7d9c/tumblr_pg2wu1L9DM1trd056o2_500h.png
+    # https://media.tumblr.com/701a535af224f89684d2cfcc097575ef/tumblr_pjsx70RakC1y0gqjko1_1280.pnj
     in _, directory, file if image_url?
       @directory = directory
       parse_filename
@@ -87,6 +88,7 @@ class Source::URL::Tumblr < Source::URL
     # https://68.media.tumblr.com/ee02048f5578595badc95905e17154b4/tumblr_inline_ofbr4452601sk4jd9_250.gif
     # https://media.tumblr.com/ee02048f5578595badc95905e17154b4/tumblr_inline_ofbr4452601sk4jd9_500.gif
     # https://66.media.tumblr.com/b9395771b2d0435fe4efee926a5a7d9c/tumblr_pg2wu1L9DM1trd056o2_500h.png
+    # https://media.tumblr.com/701a535af224f89684d2cfcc097575ef/tumblr_pjsx70RakC1y0gqjko1_1280.pnj
     # https://25.media.tumblr.com/tumblr_m2dxb8aOJi1rop2v0o1_500.png
     # https://media.tumblr.com/0DNBGJovY5j3smfeQs8nB53z_500.jpg
     in *words, /\A\d+h?|raw\z/ => size

test/unit/sources/tumblr_test.rb

@@ -245,6 +245,26 @@ module Sources
       )
     end
 
+    context "A *.media.tumblr.com/tumblr_$id_$size.pnj URL" do
+      strategy_should_work(
+        "https://media.tumblr.com/701a535af224f89684d2cfcc097575ef/tumblr_pjsx70RakC1y0gqjko1_1280.pnj",
+        image_urls: ["https://media.tumblr.com/701a535af224f89684d2cfcc097575ef/tumblr_pjsx70RakC1y0gqjko1_1280.pnj"],
+        page_url: nil,
+        artist_name: nil,
+        download_size: 296_595,
+      )
+    end
+
+    context "A va.media.tumblr.com/tumblr_$id.mp4 URL" do
+      strategy_should_work(
+        "https://va.media.tumblr.com/tumblr_pgohk0TjhS1u7mrsl.mp4",
+        image_urls: ["https://va.media.tumblr.com/tumblr_pgohk0TjhS1u7mrsl.mp4"],
+        page_url: nil,
+        artist_name: nil,
+        download_size: 7_960_082,
+      )
+    end
+
     context "generating page urls" do
       should "work" do
         source1 = "https://octrain1020.tumblr.com/post/190713122589"
@@ -272,6 +292,7 @@ module Sources
       assert(Source::URL.image_url?("https://68.media.tumblr.com/ee02048f5578595badc95905e17154b4/tumblr_inline_ofbr4452601sk4jd9_250.gif"))
       assert(Source::URL.image_url?("https://media.tumblr.com/ee02048f5578595badc95905e17154b4/tumblr_inline_ofbr4452601sk4jd9_500.gif"))
       assert(Source::URL.image_url?("https://66.media.tumblr.com/b9395771b2d0435fe4efee926a5a7d9c/tumblr_pg2wu1L9DM1trd056o2_500h.png"))
+      assert(Source::URL.image_url?("https://media.tumblr.com/701a535af224f89684d2cfcc097575ef/tumblr_pjsx70RakC1y0gqjko1_1280.pnj"))
 
       assert(Source::URL.image_url?("https://25.media.tumblr.com/tumblr_m2dxb8aOJi1rop2v0o1_500.png"))
       assert(Source::URL.image_url?("https://media.tumblr.com/tumblr_m2dxb8aOJi1rop2v0o1_1280.png"))