discourse/spec/lib/email/styles_spec.rb

# frozen_string_literal: true

require "email"

RSpec.describe Email::Styles do
  let(:attachments) { {} }

  def basic_fragment(html)
    styler = Email::Styles.new(html)
    styler.format_basic
    Nokogiri::HTML5.fragment(styler.to_html)
  end

  def html_fragment(html)
    styler = Email::Styles.new(html)
    styler.format_basic
    styler.format_html
    Nokogiri::HTML5.fragment(styler.to_html)
  end

  describe "basic formatter" do
    it "adds a max-width to large images" do
      frag = basic_fragment("<img height='auto' width='auto' src='gigantic.jpg'>")
      expect(frag.at("img")["style"]).to match("max-width")
    end

    it "adds a width and height to emojis" do
      frag = basic_fragment("<img src='/images/emoji/fish.png' class='emoji'>")
      expect(frag.at("img")["width"]).to eq("20")
      expect(frag.at("img")["height"]).to eq("20")
    end

    it "adds a width and height to custom emojis" do
      frag =
        basic_fragment("<img src='/uploads/default/_emoji/fish.png' class='emoji emoji-custom'>")
      expect(frag.at("img")["width"]).to eq("20")
      expect(frag.at("img")["height"]).to eq("20")
    end

    it "converts relative paths to absolute paths" do
      frag = basic_fragment("<img src='/some-image.png'>")
      expect(frag.at("img")["src"]).to eq("#{Discourse.base_url}/some-image.png")
    end

    it "strips classes and ids" do
      frag = basic_fragment("<div class='foo' id='bar'><div class='foo' id='bar'></div></div>")
      expect(frag.to_html).to eq("<div><div></div></div>")
    end
  end

  describe "html template formatter" do
    it "attaches a style to h3 tags" do
      frag = html_fragment("<h3>hello</h3>")
      expect(frag.at("h3")["style"]).to be_present
    end

    it "attaches a style to hr tags" do
      frag = html_fragment("hello<hr>")
      expect(frag.at("hr")["style"]).to be_present
    end

    it "attaches a style to a tags" do
      frag = html_fragment("<a href>wat</a>")
      expect(frag.at("a")["style"]).to be_present
    end

    it "attaches a style to ul and li tags" do
      frag = html_fragment("<ul><li>hello</li></ul>")
      expect(frag.at("ul")["style"]).to be_present
      expect(frag.at("li")["style"]).to be_present
    end

    it "converts iframes to links" do
      iframe_url = "http://www.youtube.com/embed/7twifrxOTQY?feature=oembed&wmode=opaque"
      frag = html_fragment("<iframe src=\"#{iframe_url}\"></iframe>")
      expect(frag.at("iframe")).to be_blank
      expect(frag.at("a")).to be_present
      expect(frag.at("a")["href"]).to eq(iframe_url)
    end

    it "won't allow non URLs in iframe src, strips them with no link" do
      iframe_url = "alert('xss hole')"
      frag = html_fragment("<iframe src=\"#{iframe_url}\"></iframe>")
      expect(frag.at("iframe")).to be_blank
      expect(frag.at("a")).to be_blank
    end

    it "won't allow empty iframe src, strips them with no link" do
      frag = html_fragment("<iframe src=''></iframe>")
      expect(frag.at("iframe")).to be_blank
      expect(frag.at("a")).to be_blank
    end

    it "prefers data-original-href attribute to get iframe link" do
      original_url = "https://vimeo.com/329875646/85f1546a42"
      iframe_url = "https://player.vimeo.com/video/329875646"
      frag =
        html_fragment(
          "<iframe src=\"#{iframe_url}\" data-original-href=\"#{original_url}\"></iframe>",
        )
      expect(frag.at("iframe")).to be_blank
      expect(frag.at("a")).to be_present
      expect(frag.at("a")["href"]).to eq(original_url)
    end

    it "replaces hashtag-cooked text with raw #hashtag" do
      category = Fabricate(:category, name: "dev", slug: "dev")
      post = Fabricate(:post, raw: "this is #dev")
      post.rebake!
      hashtag_html = post.cooked
      frag = html_fragment(hashtag_html)
      expect(frag.at("a").text.chomp).to eq("#dev")
    end
  end

  describe "rewriting protocol relative URLs to the forum" do
    it "doesn't rewrite a url to another site" do
      frag = html_fragment('<a href="//youtube.com/discourse">hello</a>')
      expect(frag.at("a")["href"]).to eq("//youtube.com/discourse")
    end

    context "without https" do
      before { SiteSetting.force_https = false }

      it "rewrites the href to have http" do
        frag = html_fragment('<a href="//test.localhost/discourse">hello</a>')
        expect(frag.at("a")["href"]).to eq("http://test.localhost/discourse")
      end

      it "rewrites the href for attachment files to have http" do
        frag =
          html_fragment(
            '<a class="attachment" href="//try-discourse.global.ssl.fastly.net/uploads/default/368/40b610b0aa90cfcf.txt">attachment_file.txt</a>',
          )
        expect(frag.at("a")["href"]).to eq(
          "http://try-discourse.global.ssl.fastly.net/uploads/default/368/40b610b0aa90cfcf.txt",
        )
      end

      it "rewrites the src to have http" do
        frag = html_fragment('<img src="//test.localhost/blah.jpg">')
        expect(frag.at("img")["src"]).to eq("http://test.localhost/blah.jpg")
      end
    end

    context "with https" do
      before { SiteSetting.force_https = true }

      it "rewrites the forum URL to have https" do
        frag = html_fragment('<a href="//test.localhost/discourse">hello</a>')
        expect(frag.at("a")["href"]).to eq("https://test.localhost/discourse")
      end

      it "rewrites the href for attachment files to have https" do
        frag =
          html_fragment(
            '<a class="attachment" href="//try-discourse.global.ssl.fastly.net/uploads/default/368/40b610b0aa90cfcf.txt">attachment_file.txt</a>',
          )
        expect(frag.at("a")["href"]).to eq(
          "https://try-discourse.global.ssl.fastly.net/uploads/default/368/40b610b0aa90cfcf.txt",
        )
      end

      it "rewrites the src to have https" do
        frag = html_fragment('<img src="//test.localhost/blah.jpg">')
        expect(frag.at("img")["src"]).to eq("https://test.localhost/blah.jpg")
      end
    end
  end

  describe "deduplicate styles" do
    it "removes double definitions" do
      frag = "<test style='color:green;color:red'>hello</test>"

      styler = Email::Styles.new(frag)
      styled = styler.to_html
      styled = Nokogiri::HTML5.fragment(styled)
      expect(styled.at("test")["style"]).to eq("color:red")
    end
    it "handles whitespace correctly" do
      frag =
        "<test style=' color :  green ; ; ;   color :    red; background:white;  background:yellow '>hello</test>"
      styler = Email::Styles.new(frag)
      styled = styler.to_html
      styled = Nokogiri::HTML5.fragment(styled)
      expect(styled.at("test")["style"]).to eq("color:red;background:yellow")
    end
  end

  describe "dark mode emails" do
    it "adds dark_mode_styles when site setting active" do
      frag = html_fragment('<div class="body">test</div>')
      styler = Email::Styles.new(frag)
      styler.format_basic
      styler.format_html
      @frag = Nokogiri::HTML5.fragment(styler.to_s)

      # dark mode attribute
      expect(@frag.css('[dm="body"]')).to be_present
    end
  end

  describe "strip_avatars_and_emojis" do
    it "works for lonesome emoji with no title" do
      emoji = "<img src='/images/emoji/twitter/crying_cat_face.png'>"
      style = Email::Styles.new(emoji)
      style.strip_avatars_and_emojis
      expect(style.to_html).to match_html(emoji)
    end

    it "works for lonesome emoji with title" do
      emoji = "<img title='cry_cry' src='/images/emoji/twitter/crying_cat_face.png'>"
      style = Email::Styles.new(emoji)
      style.strip_avatars_and_emojis
      expect(style.to_html).to match_html("cry_cry")
    end

    it "works if img tag has no attrs" do
      cooked =
        "Create a method for click on image and use ng-click in <img> in your slide box...it is simple"
      style = Email::Styles.new(cooked)
      style.strip_avatars_and_emojis
      expect(style.to_html).to include(cooked)
    end
  end

  describe "onebox_styles" do
    it "renders quote as <blockquote>" do
      fragment =
        html_fragment(
          '<aside class="quote"> <div class="title"> <div class="quote-controls"> <i class="fa fa-chevron-down" title="expand/collapse"></i><a href="/t/xyz/123" title="go to the quoted post" class="back"></a> </div> <img alt="" width="20" height="20" src="https://cdn-enterprise.discourse.org/boingboing/user_avatar/bbs.boingboing.net/techapj/40/54379_1.png" class="avatar">techAPJ: </div> <blockquote> <p>lorem ipsum</p> </blockquote> </aside>',
        )
      expect(fragment.to_s.squish).to match(%r{^<blockquote.+</blockquote>$})
    end

    it "removes GitHub excerpts" do
      stub_request(:head, "https://github.com/discourse/discourse/pull/1253").to_return(
        status: 200,
        body: "",
        headers: {
        },
      )
      stub_request(:get, "https://api.github.com/repos/discourse/discourse/pulls/1253").to_return(
        status: 200,
        body: onebox_response("githubpullrequest"),
      )

      onebox = Oneboxer.onebox("https://github.com/discourse/discourse/pull/1253")
      fragment = html_fragment(onebox)
      expect(fragment.css(".github-body-container .excerpt")).to be_empty
    end
  end

  describe "replace_secure_uploads_urls" do
    before do
      setup_s3
      SiteSetting.secure_uploads = true
    end

    let(:attachments) { { "testimage.png" => stub(url: "email/test.png") } }
    it "replaces secure uploads within a link with a placeholder" do
      frag =
        html_fragment(
          "<a href=\"#{Discourse.base_url}\/secure-uploads/original/1X/testimage.png\"><img src=\"/secure-uploads/original/1X/testimage.png\"></a>",
        )
      expect(frag.at("img")).not_to be_present
      expect(frag.to_s).to include("Redacted")
    end

    it "replaces secure images with a placeholder" do
      frag = html_fragment("<img src=\"/secure-uploads/original/1X/testimage.png\">")
      expect(frag.at("img")).not_to be_present
      expect(frag.to_s).to include("Redacted")
    end

    it "does not replace topic links with secure-uploads in the name" do
      frag =
        html_fragment("<a href=\"#{Discourse.base_url}\/t/secure-uploads/235723\">Visit Topic</a>")
      expect(frag.to_s).not_to include("Redacted")
    end

    it "works in lightboxes with missing srcset attribute" do
      frag =
        html_fragment(
          "<a href=\"#{Discourse.base_url}\/secure-uploads/original/1X/testimage.png\" class=\"lightbox\"><img src=\"/secure-uploads/original/1X/testimage.png\"></a>",
        )
      expect(frag.at("img")).not_to be_present
      expect(frag.to_s).to include("Redacted")
    end

    it "works in lightboxes with srcset attribute set" do
      frag = html_fragment(<<~HTML)
          <a href="#{Discourse.base_url}/secure-uploads/original/1X/testimage.png" class="lightbox">
            <img src="/secure-uploads/original/1X/testimage.png" srcset="/secure-uploads/optimized/1X/testimage.png, /secure-uploads/original/1X/testimage.png 1.5x" />
          </a>
        HTML

      expect(frag.at("img")).not_to be_present
      expect(frag.to_s).to include("Redacted")
    end

    it "skips links with no images as children" do
      frag =
        html_fragment(
          "<a href=\"#{Discourse.base_url}\/secure-uploads/original/1X/testimage.png\"><span>Clearly not an image</span></a>",
        )
      expect(frag.to_s).to include("not an image")
    end
  end

  describe "#inline_secure_images" do
    before do
      setup_s3
      SiteSetting.secure_uploads = true
    end

    fab!(:upload) do
      Fabricate(:upload, original_filename: "testimage.png", secure: true, sha1: "123456")
    end
    let(:attachments) { [stub(url: "cid:email/test.png")] }
    let(:attachments_index) { { upload.sha1 => 0 } }
    let(:html) do
      "<a href=\"#{Discourse.base_url}\/secure-uploads/original/1X/123456.png\"><img src=\"/secure-uploads/original/1X/123456.png\" width=\"20\" height=\"30\"></a>"
    end

    def strip_and_inline
      # strip out the secure uploads
      styler = Email::Styles.new(html)
      styler.format_basic
      styler.format_html
      html = styler.to_html

      # pass in the attachments to match uploads based on sha + original filename
      styler = Email::Styles.new(html)
      styler.inline_secure_images(attachments, attachments_index)
      @frag = Nokogiri::HTML5.fragment(styler.to_s)
    end

    it "inlines attachments where stripped-secure-media data attr is present" do
      strip_and_inline
      expect(@frag.to_s).to include("cid:email/test.png")
      expect(@frag.css("[data-stripped-secure-upload]")).not_to be_present
      expect(@frag.children.attr("style").value).to eq("width: 20px; height: 30px;")
    end

    it "does not inline anything if the upload cannot be found" do
      upload.update(sha1: "blah12")
      strip_and_inline

      expect(@frag.to_s).not_to include("cid:email/test.png")
      expect(@frag.css("[data-stripped-secure-upload]")).to be_present
    end

    context "when an optimized image is used instead of the original" do
      let(:html) do
        "<a href=\"#{Discourse.base_url}\/secure-uploads/optimized/2X/1/123456_2_20x30.png\"><img src=\"/secure-uploads/optimized/2X/1/123456_2_20x30.png\" width=\"20\" height=\"30\"></a>"
      end

      it "inlines attachments where the stripped-secure-media data attr is present" do
        optimized = Fabricate(:optimized_image, upload: upload, width: 20, height: 30)
        strip_and_inline
        expect(@frag.to_s).to include("cid:email/test.png")
        expect(@frag.css("[data-stripped-secure-upload]")).not_to be_present
        expect(@frag.children.attr("style").value).to eq("width: 20px; height: 30px;")
      end
    end

    context "when inlining an originally oneboxed image" do
      before { SiteSetting.authorized_extensions = "*" }

      let(:siteicon) { Fabricate(:upload, original_filename: "siteicon.ico") }
      let(:attachments) { [stub(url: "cid:email/test.png"), stub(url: "cid:email/test2.ico")] }
      let(:attachments_index) { { upload.sha1 => 0, siteicon.sha1 => 1 } }
      let(:html) { <<~HTML }
<aside class="onebox allowlistedgeneric">
  <header class="source">
      <img src="#{Discourse.base_url}/secure-uploads/original/1X/#{siteicon.sha1}.ico" class="site-icon" width="64" height="64">
      <a href="https://test.com/article" target="_blank" rel="noopener" title="02:33PM - 24 October 2020">Test</a>
  </header>
  <article class="onebox-body">
    <div class="aspect-image" style="--aspect-ratio:20/30;"><img src="#{Discourse.base_url}/secure-uploads/optimized/2X/1/123456_2_20x30.png" class="thumbnail d-lazyload" width="20" height="30" srcset="#{Discourse.base_url}/secure-uploads/optimized/2X/1/123456_2_20x30.png"></div>

<h3><a href="https://test.com/article" target="_blank" rel="noopener">Test</a></h3>

<p>This is a test onebox.</p>

  </article>
  <div class="onebox-metadata">
  </div>
  <div style="clear: both"></div>
</aside>
        HTML

      it "keeps the special site icon width and height and onebox styles" do
        optimized = Fabricate(:optimized_image, upload: upload, width: 20, height: 30)
        strip_and_inline
        expect(@frag.to_s).to include("cid:email/test.png")
        expect(@frag.to_s).to include("cid:email/test2.ico")
        expect(@frag.css("[data-stripped-secure-upload]")).not_to be_present
        expect(@frag.css("[data-embedded-secure-image]")[0].attr("style")).to eq(
          "width: 16px; height: 16px;",
        )
        expect(@frag.css("[data-embedded-secure-image]")[1].attr("style")).to eq(
          "width: 60px; max-height: 80%; max-width: 20%; height: auto; float: left; margin-right: 10px;",
        )
      end

      context "when inlining a oneboxed image with a direct parent of onebox-body" do
        let(:html) { <<~HTML }
<aside class="onebox allowlistedgeneric">
  <header class="source">
      <img src="#{Discourse.base_url}/secure-uploads/original/1X/#{siteicon.sha1}.ico" class="site-icon" width="64" height="64">
      <a href="https://test.com/article" target="_blank" rel="noopener" title="02:33PM - 24 October 2020">Test</a>
  </header>
  <article class="onebox-body">
    <img src="#{Discourse.base_url}/secure-uploads/original/1X/123456.png" class="thumbnail onebox-avatar" width="20" height="30">

<h3><a href="https://test.com/article" target="_blank" rel="noopener">Test</a></h3>

<p>This is a test onebox.</p>

  </article>
  <div class="onebox-metadata">
  </div>
  <div style="clear: both"></div>
</aside>
          HTML

        it "keeps the special onebox styles" do
          strip_and_inline
          expect(@frag.to_s).to include("cid:email/test.png")
          expect(@frag.to_s).to include("cid:email/test2.ico")
          expect(@frag.css("[data-stripped-secure-upload]")).not_to be_present
          expect(@frag.css("[data-embedded-secure-image]")[1].attr("style")).to eq(
            "width: 60px; max-height: 80%; max-width: 20%; height: auto; float: left; margin-right: 10px;",
          )
        end
      end

      context "when there is an inline-avatar in the onebox" do
        let(:html) { <<~HTML }
<p><a class="mention" href="/u/martin">@martin</a> check this out:</p>
<aside class="onebox githubpullrequest">
  <header class="source">
      <a href="https://github.com/discourse/discourse/pull/11140" target="_blank" rel="noopener">github.com/discourse/discourse</a>
  </header>
  <article class="onebox-body">
    <div class="github-row">
  <div class="github-info-container">
    <h4>
      <a href="https://github.com/discourse/discourse/pull/11140" target="_blank" rel="noopener">FEATURE: Implement edit functionality for post notices</a>
    </h4>
    <div class="branches">
      <code>discourse:master</code> ← <code>discourse:feature/post_notices_edit</code>
    </div>

    <div class="github-info">
      <div class="date">
        opened <span class="discourse-local-date" data-format="ll" data-date="2020-11-05" data-time="20:33:53" data-timezone="UTC">08:33PM - 05 Nov 20 UTC</span>
      </div>
      <div class="user">
        <a href="https://github.com/udan11" target="_blank" rel="noopener">
          <img alt="udan11" src="#{Discourse.base_url}/secure-uploads/original/1X/123456.png" class="onebox-avatar-inline" width="20" height="20">
          udan11
        </a>
      </div>
      <div class="lines" title="2 commits changed 27 files with 250 additions and 224 deletions">
        <a href="https://github.com/discourse/discourse/pull/11140/files" target="_blank" rel="noopener">
          <span class="added">+250</span>
          <span class="removed">-224</span>
        </a>
      </div>
    </div>
  </div>
</div>
  </article>
  <div class="onebox-metadata">
  </div>
  <div style="clear: both"></div>
</aside>
          HTML
        it "keeps the special onebox styles" do
          strip_and_inline
          expect(@frag.to_s).to include("cid:email/test.png")
          expect(@frag.css("[data-stripped-secure-upload]")).not_to be_present
          expect(@frag.css("[data-embedded-secure-image]")[0].attr("style")).to eq(
            "width: 20px; height: 20px; float: none; vertical-align: middle; max-height: 80%; max-width: 20%; height: auto; float: left; margin-right: 10px;",
          )
        end
      end
    end
  end
end