サムネ取得 API 見直し (#398) (#402)

Reviewed-on: #402 Co-authored-by: miteruzo <miteruzo@naver.com> Co-committed-by: miteruzo <miteruzo@naver.com>
2026-07-10 01:27:11 +09:00
@@ -1,28 +1,46 @@
-require "rails_helper"
+require 'rails_helper'


-RSpec.describe "Preview", type: :request do
-  describe "GET /preview/title" do
-    it "401 unless logged in" do
+RSpec.describe 'Preview', type: :request do
+  describe 'GET /preview/title' do
+    it '401 unless logged in' do
      sign_out
-      get "/preview/title", params: { url: "example.com" }
+      get '/preview/title', params: { url: 'example.com' }
      expect(response).to have_http_status(:unauthorized)
    end

-    it "400 when url blank" do
-      sign_in_as(create(:user))
-      get "/preview/title", params: { url: "" }
+    it '403 when logged in as guest' do
+      sign_in_as(create(:user, :guest))
+      get '/preview/title', params: { url: 'example.com' }
+      expect(response).to have_http_status(:forbidden)
+    end
+
+    it '400 when url blank' do
+      sign_in_as(create(:user, :member))
+      get '/preview/title', params: { url: '' }
      expect(response).to have_http_status(:bad_request)
    end

-    it "returns parsed title (stubbing URI.open)" do
-      sign_in_as(create(:user))
-      fake_html = "<html><head><title>  Hello  </title></head></html>"
-      allow(URI).to receive(:open).and_return(StringIO.new(fake_html))
+    it 'returns parsed title' do
+      sign_in_as(create(:user, :member))
+      allow(Preview::ThumbnailFetcher)
+          .to receive(:title)
+          .with('example.com')
+          .and_return('Hello')

-      get "/preview/title", params: { url: "example.com" }
+      get '/preview/title', params: { url: 'example.com' }
      expect(response).to have_http_status(:ok)
-      expect(json["title"]).to eq("Hello")
+      expect(json['title']).to eq('Hello')
+    end
+
+    it '413 when fetched response is too large' do
+      sign_in_as(create(:user, :member))
+      allow(Preview::ThumbnailFetcher)
+          .to receive(:title)
+          .and_raise(Preview::HttpFetcher::ResponseTooLarge, '外部データが大きすぎます．')
+
+      get '/preview/title', params: { url: 'example.com' }
+      expect(response).to have_http_status(:payload_too_large)
    end
  end
 end
@@ -0,0 +1,23 @@
+require 'rails_helper'
+
+RSpec.describe Preview::HttpFetcher do
+  describe '.fetch' do
+    it 'raises FetchFailed when redirect location is invalid' do
+      redirect = Net::HTTPFound.new('1.1', '302', 'Found')
+      redirect['location'] = 'http://[invalid'
+
+      allow(Preview::UrlSafety).to receive(:validate)
+          .with('https://example.com/page')
+          .and_return([URI.parse('https://example.com/page'), ['203.0.113.10']])
+      allow(described_class).to receive(:request)
+          .and_return(redirect)
+      allow(Rails.logger).to receive(:warn)
+
+      expect {
+        described_class.fetch('https://example.com/page')
+      }.to raise_error(Preview::HttpFetcher::FetchFailed)
+      expect(Rails.logger).to have_received(:warn)
+          .with(/invalid_redirect_location/)
+    end
+  end
+end
@@ -0,0 +1,51 @@
+require 'rails_helper'
+
+RSpec.describe Preview::ThumbnailFetcher do
+  describe '.fetch' do
+    it 'rejects svg thumbnails' do
+      page = Preview::HttpFetcher::Response.new(
+          '<meta property="og:image" content="https://example.com/thumb.svg">',
+          'text/html',
+          'https://example.com/page')
+      svg = Preview::HttpFetcher::Response.new(
+          '<svg></svg>',
+          'image/svg+xml',
+          'https://example.com/thumb.svg')
+
+      allow(Preview::UrlSafety).to receive(:validate)
+          .and_return([URI.parse('https://example.com/page'), ['203.0.113.10']])
+      allow(Preview::HttpFetcher).to receive(:fetch)
+          .with('https://example.com/page', max_bytes: described_class::HTML_MAX_BYTES)
+          .and_return(page)
+      allow(Preview::HttpFetcher).to receive(:fetch)
+          .with('https://example.com/thumb.svg')
+          .and_return(svg)
+
+      expect {
+        described_class.fetch('https://example.com/page')
+      }.to raise_error(Preview::ThumbnailFetcher::GenerationFailed)
+    end
+
+    it 'accepts allowed image content type with parameters' do
+      page = Preview::HttpFetcher::Response.new(
+          '<meta property="og:image" content="https://example.com/thumb.jpg">',
+          'text/html',
+          'https://example.com/page')
+      image = Preview::HttpFetcher::Response.new(
+          'jpeg-bytes',
+          'image/jpeg; charset=binary',
+          'https://example.com/thumb.jpg')
+
+      allow(Preview::UrlSafety).to receive(:validate)
+          .and_return([URI.parse('https://example.com/page'), ['203.0.113.10']])
+      allow(Preview::HttpFetcher).to receive(:fetch)
+          .with('https://example.com/page', max_bytes: described_class::HTML_MAX_BYTES)
+          .and_return(page)
+      allow(Preview::HttpFetcher).to receive(:fetch)
+          .with('https://example.com/thumb.jpg')
+          .and_return(image)
+
+      expect(described_class.fetch('https://example.com/page')).to eq('jpeg-bytes')
+    end
+  end
+end
@@ -0,0 +1,15 @@
+require 'rails_helper'
+
+RSpec.describe Preview::UrlSafety do
+  describe '.validate' do
+    it 'raises UnsafeUrl when DNS resolution fails' do
+      allow(Resolv).to receive(:getaddresses)
+          .with('missing.example')
+          .and_raise(Resolv::ResolvError)
+
+      expect {
+        described_class.validate('https://missing.example')
+      }.to raise_error(Preview::UrlSafety::UnsafeUrl)
+    end
+  end
+end