Use PDFLab to render PDFs in GitLab

app/assets/javascripts/blob/pdf/index.js

+/* eslint-disable no-new */
+import Vue from 'vue';
+import PDFLab from 'vendor/pdflab';
+import workerSrc from 'vendor/pdf.worker';
+
+Vue.use(PDFLab, {
+  workerSrc,
+});
+
+export default () => {
+  const el = document.getElementById('js-pdf-viewer');
+
+  new Vue({
+    el,
+    data() {
+      return {
+        error: false,
+        loadError: false,
+        loading: true,
+        pdf: el.dataset.endpoint,
+      };
+    },
+    methods: {
+      onLoad() {
+        this.loading = false;
+      },
+      onError(error) {
+        this.loading = false;
+        this.loadError = true;
+        this.error = error;
+      },
+    },
+    template: `
+      <div class="container-fluid md prepend-top-default append-bottom-default">
+        <div
+          class="text-center loading"
+          v-if="loading && !error">
+          <i
+            class="fa fa-spinner fa-spin"
+            aria-hidden="true"
+            aria-label="PDF loading">
+          </i>
+        </div>
+        <pdf-lab
+          v-if="!loadError"
+          :pdf="pdf"
+          @pdflabload="onLoad"
+          @pdflaberror="onError" />
+        <p
+          class="text-center"
+          v-if="error">
+          <span v-if="loadError">
+            An error occured whilst loading the file. Please try again later.
+          </span>
+          <span v-else>
+            An error occured whilst decoding the file.
+          </span>
+        </p>
+      </div>
+    `,
+  });
+};

app/assets/javascripts/blob/pdf_viewer.js

+import renderPDF from './pdf';
+
+document.addEventListener('DOMContentLoaded', renderPDF);

app/models/blob.rb

@@ -46,6 +46,10 @@ class Blob < SimpleDelegator
     text? && language && language.name == 'SVG'
   end
+  def pdf?
+    name && File.extname(name) == '.pdf'
+  end
+
   def ipython_notebook?
     text? && language&.name == 'Jupyter Notebook'
   end
@@ -71,6 +75,8 @@ class Blob < SimpleDelegator
       end
     elsif image? || svg?
       'image'
+    elsif pdf?
+      'pdf'
     elsif ipython_notebook?
       'notebook'
     elsif sketch?

app/views/projects/blob/_pdf.html.haml

+- content_for :page_specific_javascripts do
+  = page_specific_javascript_bundle_tag('common_vue')
+  = page_specific_javascript_bundle_tag('pdf_viewer')
+
+.file-content#js-pdf-viewer{ data: { endpoint: namespace_project_raw_path(@project.namespace, @project, @id) } }

config/webpack.config.js

@@ -38,6 +38,7 @@ var config = {
     network:              './network/network_bundle.js',
     notebook_viewer:      './blob/notebook_viewer.js',
     sketch_viewer:        './blob/sketch_viewer.js',
+    pdf_viewer:           './blob/pdf_viewer.js',
     profile:              './profile/profile_bundle.js',
     protected_branches:   './protected_branches/protected_branches_bundle.js',
     snippet:              './snippet/snippet_bundle.js',
@@ -65,7 +66,11 @@ var config = {
       {
         test: /\.svg$/,
         use: 'raw-loader'
-      }
+      }, {
+        test: /\.(worker.js|pdf)$/,
+        exclude: /node_modules/,
+        loader: 'file-loader',
+      },
     ]
   },
@@ -107,6 +112,7 @@ var config = {
         'issuable',
         'merge_conflicts',
         'notebook_viewer',
+        'pdf_viewer',
         'vue_pipelines',
       ],
       minChunks: function(module, count) {

package.json

@@ -24,6 +24,7 @@
     "document-register-element": "^1.3.0",
     "dropzone": "^4.2.0",
     "emoji-unicode-version": "^0.2.1",
+    "file-loader": "^0.11.1",
     "jquery": "^2.2.1",
     "jquery-ujs": "^1.2.1",
     "js-cookie": "^2.1.3",

spec/javascripts/blob/pdf/index_spec.js

+import renderPDF from '~/blob/pdf';
+import testPDF from './test.pdf';
+
+describe('PDF renderer', () => {
+  let viewer;
+  preloadFixtures('static/pdf_viewer.html.raw');
+
+  beforeEach(() => {
+    loadFixtures('static/pdf_viewer.html.raw');
+    viewer = document.getElementById('js-pdf-viewer');
+    viewer.dataset.endpoint = testPDF;
+  });
+
+  it('shows loading icon', () => {
+    renderPDF();
+
+    expect(
+      document.querySelector('.loading'),
+    ).not.toBeNull();
+  });
+
+  describe('successful response', () => {
+    beforeEach((done) => {
+      renderPDF();
+
+      setTimeout(() => {
+        done();
+      }, 500);
+    });
+
+    it('does not show loading icon', () => {
+      expect(
+        document.querySelector('.loading'),
+      ).toBeNull();
+    });
+
+    it('renders the PDF', () => {
+      expect(
+        document.querySelector('.pdf-viewer'),
+      ).not.toBeNull();
+    });
+
+    it('renders the PDF page', () => {
+      expect(
+        document.querySelector('.pdf-page'),
+      ).not.toBeNull();
+    });
+  });
+
+  describe('error getting file', () => {
+    beforeEach((done) => {
+      viewer.dataset.endpoint = 'invalid/endpoint';
+      renderPDF();
+
+      setTimeout(() => {
+        done();
+      }, 500);
+    });
+
+    it('does not show loading icon', () => {
+      expect(
+        document.querySelector('.loading'),
+      ).toBeNull();
+    });
+
+    it('shows error message', () => {
+      expect(
+        document.querySelector('.md').textContent.trim(),
+      ).toBe('An error occured whilst loading the file. Please try again later.');
+    });
+  });
+});

spec/javascripts/fixtures/pdf_viewer.html.haml

+.file-content#js-pdf-viewer{ data: { endpoint: '/test' } }

spec/models/blob_spec.rb

@@ -53,6 +53,20 @@ describe Blob do
     end
   end
+  describe '#pdf?' do
+    it 'is falsey when file extension is not .pdf' do
+      git_blob = double(name: 'git_blob.txt')
+
+      expect(described_class.decorate(git_blob)).not_to be_pdf
+    end
+
+    it 'is truthy when file extension is .pdf' do
+      git_blob = double(name: 'git_blob.pdf')
+
+      expect(described_class.decorate(git_blob)).to be_pdf
+    end
+  end
+
   describe '#ipython_notebook?' do
     it 'is falsey when language is not Jupyter Notebook' do
       git_blob = double(text?: true, language: double(name: 'JSON'))
@@ -102,6 +116,7 @@ describe Blob do
     def stubbed_blob(overrides = {})
       overrides.reverse_merge!(
+        name: nil,
         image?: false,
         language: nil,
         lfs_pointer?: false,
@@ -146,6 +161,11 @@ describe Blob do
       expect(blob.to_partial_path(project)).to eq 'download'
     end
+    it 'handles PDFs' do
+      blob = stubbed_blob(name: 'blob.pdf', pdf?: true)
+      expect(blob.to_partial_path(project)).to eq 'pdf'
+    end
+
     it 'handles iPython notebooks' do
       blob = stubbed_blob(text?: true, ipython_notebook?: true)
       expect(blob.to_partial_path(project)).to eq 'notebook'

yarn.lock

@@ -1942,6 +1942,12 @@ file-entry-cache@^2.0.0:
     flat-cache "^1.2.1"
     object-assign "^4.0.1"
+file-loader@^0.11.1:
+  version "0.11.1"
+  resolved "https://registry.yarnpkg.com/file-loader/-/file-loader-0.11.1.tgz#6b328ee1234a729e4e47d36375dd6d35c0e1db84"
+  dependencies:
+    loader-utils "^1.0.2"
+
 filename-regex@^2.0.0:
   version "2.0.0"
   resolved "https://registry.yarnpkg.com/filename-regex/-/filename-regex-2.0.0.tgz#996e3e80479b98b9897f15a8a58b3d084e926775"
@@ -2923,6 +2929,14 @@ loader-utils@^0.2.11, loader-utils@^0.2.16, loader-utils@^0.2.5:
     json5 "^0.5.0"
     object-assign "^4.0.1"
+loader-utils@^1.0.2:
+  version "1.1.0"
+  resolved "https://registry.yarnpkg.com/loader-utils/-/loader-utils-1.1.0.tgz#c98aef488bcceda2ffb5e2de646d6a754429f5cd"
+  dependencies:
+    big.js "^3.1.3"
+    emojis-list "^2.0.0"
+    json5 "^0.5.0"
+
 locate-path@^2.0.0:
   version "2.0.0"
   resolved "https://registry.yarnpkg.com/locate-path/-/locate-path-2.0.0.tgz#2b568b265eec944c6d9c0de9c3dbbbca0354cd8e"