Merge branch 'Kingdread-pdfjs'

21 files changed, 611 insertions, 4 deletions

diff --git a/.eslintignore b/.eslintignore
new file mode 100644
index 000000000..7e2863113
--- /dev/null
+++ b/.eslintignore
@@ -0,0 +1 @@
+qutebrowser/3rdparty/pdfjs/*
diff --git a/CHANGELOG.asciidoc b/CHANGELOG.asciidoc
index 018febe51..a41d3b4c4 100644
--- a/CHANGELOG.asciidoc
+++ b/CHANGELOG.asciidoc
@@ -20,6 +20,9 @@ v0.5.0 (unreleased)
 Added
 ~~~~~
 
+- Ability to preview PDFs using pdf.js in the browser if it's installed. This
+  is disabled by default and can be enabled using the
+  `content -> pdfjs-enabled` setting.
 - New setting `ui -> hide-wayland-decoration` to hide the window decoration
   when using wayland.
 - New userscripts in `misc/userscripts`:
diff --git a/MANIFEST.in b/MANIFEST.in
index 07726eca7..e2dd15509 100644
--- a/MANIFEST.in
+++ b/MANIFEST.in
@@ -3,6 +3,7 @@ recursive-include qutebrowser/html *.html
 recursive-include qutebrowser/img *.svg *.png
 recursive-include qutebrowser/test *.py
 recursive-include qutebrowser/javascript *.js
+graft qutebrowser/3rdparty
 graft icons
 graft doc/img
 graft misc
@@ -27,6 +28,7 @@ exclude qutebrowser.rcc
 exclude .coveragerc
 exclude .pylintrc
 exclude .eslintrc
+exclude .eslintignore
 exclude doc/help
 exclude .appveyor.yml
 exclude .travis.yml
diff --git a/README.asciidoc b/README.asciidoc
index ff903ce99..51c0f5803 100644
--- a/README.asciidoc
+++ b/README.asciidoc
@@ -272,3 +272,14 @@ GNU General Public License for more details.
 
 You should have received a copy of the GNU General Public License
 along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+pdf.js
+------
+
+qutebrowser optionally uses https://github.com/mozilla/pdf.js/[pdf.js] to
+display PDF files in the browser. Windows releases come with a bundled pdf.js.
+
+pdf.js is distributed under the terms of the Apache License. You can
+find a copy of the license in `qutebrowser/3rdparty/pdfjs/LICENSE` (in the
+Windows release or after running `scripts/dev/update_3rdparty.py`), or online
+http://www.apache.org/licenses/LICENSE-2.0.html[here].
diff --git a/doc/help/settings.asciidoc b/doc/help/settings.asciidoc
index 8b63eb9d5..0dc8a9e3b 100644
--- a/doc/help/settings.asciidoc
+++ b/doc/help/settings.asciidoc
@@ -165,6 +165,7 @@
 |<<content-host-block-lists,host-block-lists>>|List of URLs of lists which contain hosts to block.
 |<<content-host-blocking-enabled,host-blocking-enabled>>|Whether host blocking is enabled.
 |<<content-host-blocking-whitelist,host-blocking-whitelist>>|List of domains that should always be loaded, despite being ad-blocked.
+|<<content-enable-pdfjs,enable-pdfjs>>|Enable pdf.js to view PDF files in the browser.
 |==============
 
 .Quick reference for section ``hints''
@@ -1501,6 +1502,19 @@ Local domains are always exempt from hostblocking.
 
 Default: +pass:[piwik.org]+
 
+[[content-enable-pdfjs]]
+=== enable-pdfjs
+Enable pdf.js to view PDF files in the browser.
+
+Note that the files can still be downloaded by clicking the download button in the pdf.js viewer.
+
+Valid values:
+
+ * +true+
+ * +false+
+
+Default: +pass:[false]+
+
 == hints
 Hinting settings.
 
diff --git a/qutebrowser/browser/network/qutescheme.py b/qutebrowser/browser/network/qutescheme.py
index e74bdd2bc..876d85e1f 100644
--- a/qutebrowser/browser/network/qutescheme.py
+++ b/qutebrowser/browser/network/qutescheme.py
@@ -31,11 +31,13 @@ Module attributes:
 
 import functools
 import configparser
+import mimetypes
 
 from PyQt5.QtCore import pyqtSlot, QObject
 from PyQt5.QtNetwork import QNetworkReply
 
 import qutebrowser
+from qutebrowser.browser import pdfjs
 from qutebrowser.browser.network import schemehandler, networkreply
 from qutebrowser.utils import (version, utils, jinja, log, message, docutils,
                                objreg)
@@ -93,8 +95,11 @@ class QuteSchemeHandler(schemehandler.SchemeHandler):
             return networkreply.ErrorNetworkReply(
                 request, str(e), QNetworkReply.ContentNotFoundError,
                 self.parent())
+        mimetype, _encoding = mimetypes.guess_type(request.url().fileName())
+        if mimetype is None:
+            mimetype = 'text/html'
         return networkreply.FixedDataNetworkReply(
-            request, data, 'text/html', self.parent())
+            request, data, mimetype, self.parent())
 
 
 class JSBridge(QObject):
@@ -201,3 +206,10 @@ def qute_settings(win_id, _request):
         win_id=win_id, title='settings', config=configdata,
         confget=config_getter)
     return html.encode('UTF-8', errors='xmlcharrefreplace')
+
+
+@add_handler('pdfjs')
+def qute_pdfjs(_win_id, request):
+    """Handler for qute://pdfjs. Return the pdf.js viewer."""
+    urlpath = request.url().path()
+    return pdfjs.get_pdfjs_res(urlpath)
diff --git a/qutebrowser/browser/pdfjs.py b/qutebrowser/browser/pdfjs.py
new file mode 100644
index 000000000..83b89330c
--- /dev/null
+++ b/qutebrowser/browser/pdfjs.py
@@ -0,0 +1,175 @@
+# vim: ft=python fileencoding=utf-8 sts=4 sw=4 et:
+
+# Copyright 2015 Daniel Schadt
+#
+# This file is part of qutebrowser.
+#
+# qutebrowser is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# qutebrowser is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with qutebrowser.  If not, see <http://www.gnu.org/licenses/>.
+
+"""pdf.js integration for qutebrowser."""
+
+import os
+
+from PyQt5.QtCore import QUrl
+
+from qutebrowser.browser import webelem
+from qutebrowser.utils import utils
+
+
+class PDFJSNotFound(Exception):
+
+    """Raised when no pdf.js installation is found."""
+
+    pass
+
+
+def generate_pdfjs_page(url):
+    """Return the html content of a page that displays url with pdfjs.
+
+    Returns a string.
+
+    Args:
+        url: The url of the pdf as QUrl.
+    """
+    viewer = get_pdfjs_res('web/viewer.html').decode('utf-8')
+    script = _generate_pdfjs_script(url)
+    html_page = viewer.replace(
+        '</body>', '</body><script>{}</script>'.format(script)
+    )
+    return html_page
+
+
+def _generate_pdfjs_script(url):
+    """Generate the script that shows the pdf with pdf.js.
+
+    Args:
+        url: The url of the pdf page as QUrl.
+    """
+    return (
+        'PDFJS.verbosity = PDFJS.VERBOSITY_LEVELS.info;\n'
+        'PDFView.open("{url}");\n'
+    ).format(url=webelem.javascript_escape(url.toString(QUrl.FullyEncoded)))
+
+
+def fix_urls(asset):
+    """Take a html page and replace each relative URL wth an absolute.
+
+    This is specialized for pdf.js files and not a general purpose function.
+
+    Args:
+        asset: js file or html page as string.
+    """
+    new_urls = {
+        'viewer.css': 'qute://pdfjs/web/viewer.css',
+        'compatibility.js': 'qute://pdfjs/web/compatibility.js',
+        'locale/locale.properties':
+            'qute://pdfjs/web/locale/locale.properties',
+        'l10n.js': 'qute://pdfjs/web/l10n.js',
+        '../build/pdf.js': 'qute://pdfjs/build/pdf.js',
+        'debugger.js': 'qute://pdfjs/web/debugger.js',
+        'viewer.js': 'qute://pdfjs/web/viewer.js',
+        'compressed.tracemonkey-pldi-09.pdf': '',
+        './images/': 'qute://pdfjs/web/images/',
+        '../build/pdf.worker.js': 'qute://pdfjs/build/pdf.worker.js',
+        '../web/cmaps/': 'qute://pdfjs/web/cmaps/',
+    }
+    for original, new in new_urls.items():
+        asset = asset.replace(original, new)
+    return asset
+
+
+SYSTEM_PDFJS_PATHS = [
+    '/usr/share/pdf.js/',  # Debian pdf.js-common
+    '/usr/share/javascript/pdf/',  # Debian libjs-pdf
+    os.path.expanduser('~/.local/share/qutebrowser/pdfjs/'),  # fallback
+]
+
+
+def get_pdfjs_res(path):
+    """Get a pdf.js resource in binary format.
+
+    Args:
+        path: The path inside the pdfjs directory.
+    """
+    path = path.lstrip('/')
+    content = None
+
+    # First try a system wide installation
+    # System installations might strip off the 'build/' or 'web/' prefixes.
+    # qute expects them, so we need to adjust for it.
+    names_to_try = [path, _remove_prefix(path)]
+    for system_path in SYSTEM_PDFJS_PATHS:
+        content = _read_from_system(system_path, names_to_try)
+        if content is not None:
+            break
+
+    # Fallback to bundled pdf.js
+    if content is None:
+        res_path = '3rdparty/pdfjs/{}'.format(path)
+        try:
+            content = utils.read_file(res_path, binary=True)
+        except FileNotFoundError:
+            raise PDFJSNotFound
+
+    try:
+        # Might be script/html or might be binary
+        text_content = content.decode('utf-8')
+    except UnicodeDecodeError:
+        return content
+    text_content = fix_urls(text_content)
+    return text_content.encode('utf-8')
+
+
+def _remove_prefix(path):
+    """Remove the web/ or build/ prefix of a pdfjs-file-path.
+
+    Args:
+        path: Path as string where the prefix should be stripped off.
+    """
+    prefixes = {'web/', 'build/'}
+    if any(path.startswith(prefix) for prefix in prefixes):
+        return path.split('/', maxsplit=1)[1]
+    # Return the unchanged path if no prefix is found
+    return path
+
+
+def _read_from_system(system_path, names):
+    """Try to read a file with one of the given names in system_path.
+
+    Each file in names is considered equal, the first file that is found
+    is read and its binary content returned.
+
+    Returns None if no file could be found
+
+    Args:
+        system_path: The folder where the file should be searched.
+        names: List of possible file names.
+    """
+    for name in names:
+        try:
+            with open(os.path.join(system_path, name), 'rb') as f:
+                return f.read()
+        except OSError:
+            continue
+    return None
+
+
+def is_available():
+    """Return true if a pdfjs installation is available."""
+    try:
+        get_pdfjs_res('build/pdf.js')
+    except PDFJSNotFound:
+        return False
+    else:
+        return True
diff --git a/qutebrowser/browser/webpage.py b/qutebrowser/browser/webpage.py
index e375f721d..49a77cc8c 100644
--- a/qutebrowser/browser/webpage.py
+++ b/qutebrowser/browser/webpage.py
@@ -30,7 +30,7 @@ from PyQt5.QtPrintSupport import QPrintDialog
 from PyQt5.QtWebKitWidgets import QWebPage
 
 from qutebrowser.config import config
-from qutebrowser.browser import http, tabhistory
+from qutebrowser.browser import http, tabhistory, pdfjs
 from qutebrowser.browser.network import networkmanager
 from qutebrowser.utils import (message, usertypes, log, jinja, qtutils, utils,
                                objreg, debug)
@@ -218,6 +218,19 @@ class BrowserPage(QWebPage):
         q.deleteLater()
         return q.answer
 
+    def _show_pdfjs(self, reply):
+        """Show the reply with pdfjs."""
+        try:
+            page = pdfjs.generate_pdfjs_page(reply.url()).encode('utf-8')
+        except pdfjs.PDFJSNotFound:
+            # pylint: disable=no-member
+            # WORKAROUND for https://bitbucket.org/logilab/pylint/issue/490/
+            page = (jinja.env.get_template('no_pdfjs.html')
+                    .render(url=reply.url().toDisplayString())
+                    .encode('utf-8'))
+        self.mainFrame().setContent(page, 'text/html', reply.url())
+        reply.deleteLater()
+
     def shutdown(self):
         """Prepare the web page for being deleted."""
         self._is_shutting_down = True
@@ -305,6 +318,10 @@ class BrowserPage(QWebPage):
             else:
                 reply.finished.connect(functools.partial(
                     self.display_content, reply, 'image/jpeg'))
+        elif (mimetype in {'application/pdf', 'application/x-pdf'} and
+              config.get('content', 'enable-pdfjs')):
+            # Use pdf.js to display the page
+            self._show_pdfjs(reply)
         else:
             # Unknown mimetype, so download anyways.
             download_manager.fetch(reply,
diff --git a/qutebrowser/config/configdata.py b/qutebrowser/config/configdata.py
index 9114d7662..a9fbb2669 100644
--- a/qutebrowser/config/configdata.py
+++ b/qutebrowser/config/configdata.py
@@ -841,6 +841,11 @@ def data(readonly=False):
              "required to exactly match the requested domain.\n\n"
              "Local domains are always exempt from hostblocking."),
 
+            ('enable-pdfjs', SettingValue(typ.Bool(), 'false'),
+             "Enable pdf.js to view PDF files in the browser.\n\n"
+             "Note that the files can still be downloaded by clicking"
+             " the download button in the pdf.js viewer."),
+
             readonly=readonly
         )),
 
diff --git a/qutebrowser/html/no_pdfjs.html b/qutebrowser/html/no_pdfjs.html
new file mode 100644
index 000000000..694affc4d
--- /dev/null
+++ b/qutebrowser/html/no_pdfjs.html
@@ -0,0 +1,129 @@
+{% extends "base.html" %}
+{% block style %}
+{{ super() }}
+* {
+  margin: 0px 0px;
+  padding: 0px 0px;
+}
+
+body {
+  font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
+  -webkit-text-size-adjust: none;
+  color: #333333;
+  background-color: #EEEEEE;
+  font-size: 1.2em;
+}
+
+#error-container {
+  margin-left: 20px;
+  margin-right: 20px;
+  margin-top: 20px;
+  border: 1px solid #CCCCCC;
+  box-shadow: 0px 0px 6px rgba(0, 0, 0, 0.20);
+  border-radius: 5px;
+  background-color: #FFFFFF;
+  padding: 20px 20px;
+}
+
+#header {
+  border-bottom: 1px solid #CCC;
+}
+
+.qutebrowser-broken {
+  display: block;
+  width: 100%;
+}
+
+span.warning {
+  text-weigth: bold;
+  color: red;
+}
+
+td {
+  margin-top: 20px;
+  color: #555;
+}
+
+h1, h2 {
+  font-weight: normal;
+  color: #1e89c6;
+  margin-bottom: 10px;
+}
+
+ul {
+  margin-left: 20px;
+  margin-top: 20px;
+  margin-bottom: 20px;
+}
+
+li {
+  margin-top: 10px;
+  margin-bottom: 10px;
+}
+{% endblock %}
+
+{% block content %}
+<div id="error-container">
+  <table>
+    <tr>
+      <td style="width: 10%; vertical-align: top;">
+        <img style="width: 100%; display: block; max-width: 256px;" src="{{ resource_url('img/broken_qutebrowser_logo.png') }}" />
+      </td>
+      <td style="padding-left: 40px;">
+        <h1>No pdf.js installation found</h1>
+        <p>Error while opening {{ url }}: <br>
+        <p id="error-message-text" style="color: #a31a1a;">qutebrowser can't find a suitable pdf.js installation</p></p>
+
+        <p>It looks like you set <code>content -> enable-pdfjs</code>
+          to <em>true</em> but qutebrowser can't find the required files.</p>
+
+        <br>
+
+        <h2>Possible fixes</h2>
+        <ul>
+          <li>
+            Disable <code>content -> enable-pdfjs</code> and reload the page.
+            You will need to download the pdf-file and open it with an external
+            tool instead.
+          </li>
+
+          <li>
+            If you have installed a packaged version of qutebrowser, make sure
+            the required packages for pdf.js are also installed.
+          </li>
+
+          <li>
+            If you have installed a pdf.js package and qutebrowser still can't
+            find it, please send us a report with your system and the package
+            name, so we can add it to the list of supported packages.
+          </li>
+
+          <li>
+            If you're running a self-built version or the source version, make
+            sure you have pdf.js in <code>qutebrowser/3rdparty/pdfjs</code>.
+            You can use the <code>scripts/dev/update_3rdparty.py</code> script
+            to download the latest version.
+          </li>
+
+          <li>
+            You can manually download the pdf.js archive
+            <a href="https://mozilla.github.io/pdf.js/getting_started/#download">here</a>
+            and extract it to <code>~/.local/share/qutebrowser/pdfjs</code>
+            <br>
+            <span class="warning">Warning:</span> Using this method you are
+            responsible for yourself to keep the installation updated! If a
+            vulnerability is found in pdf.js, neither qutebrowser nor your
+            system's package manager will update your pdf.js installation.
+            Use it at your own risk!
+          </li>
+        </ul>
+
+        <p>
+          If none of these fixes work for you, please send us a bug report so
+          we can fix the issue.
+        </p>
+      </td>
+    </tr>
+  </table>
+</div>
+{% endblock %}
diff --git a/qutebrowser/utils/version.py b/qutebrowser/utils/version.py
index 7e5a185da..e96be6131 100644
--- a/qutebrowser/utils/version.py
+++ b/qutebrowser/utils/version.py
@@ -19,6 +19,7 @@
 
 """Utilities to show various version informations."""
 
+import re
 import sys
 import glob
 import os.path
@@ -34,6 +35,7 @@ from PyQt5.QtWidgets import QApplication
 
 import qutebrowser
 from qutebrowser.utils import log, utils
+from qutebrowser.browser import pdfjs
 
 
 GPL_BOILERPLATE = """
@@ -183,6 +185,25 @@ def _os_info():
     return lines
 
 
+def _pdfjs_version():
+    """Get the pdf.js version.
+
+    Return:
+        A string with the version number.
+    """
+    try:
+        pdfjs_file = pdfjs.get_pdfjs_res('build/pdf.js').decode('utf-8')
+    except pdfjs.PDFJSNotFound:
+        return 'no'
+    else:
+        version_re = re.compile(r"^PDFJS\.version = '([^']+)';$", re.MULTILINE)
+        match = version_re.search(pdfjs_file)
+        if not match:
+            return 'unknown'
+        else:
+            return match.group(1)
+
+
 def version(short=False):
     """Return a string with various version informations.
 
@@ -211,6 +232,7 @@ def version(short=False):
         lines += _module_versions()
 
         lines += [
+            'pdf.js: {}'.format(_pdfjs_version()),
             'Webkit: {}'.format(qWebKitVersion()),
             'Harfbuzz: {}'.format(os.environ.get('QT_HARFBUZZ', 'system')),
             'SSL: {}'.format(QSslSocket.sslLibraryVersionString()),
diff --git a/scripts/dev/build_release.py b/scripts/dev/build_release.py
index b4bc831b9..a90a285a6 100755
--- a/scripts/dev/build_release.py
+++ b/scripts/dev/build_release.py
@@ -35,6 +35,7 @@ sys.path.insert(0, os.path.join(os.path.dirname(__file__), os.pardir,
 
 import qutebrowser
 from scripts import utils
+from scripts.dev import update_3rdparty
 
 
 def call_script(name, *args, python=sys.executable):
@@ -89,6 +90,9 @@ def smoke_test(executable):
 
 def build_windows():
     """Build windows executables/setups."""
+    utils.print_title("Updating 3rdparty content")
+    update_3rdparty.main()
+
     utils.print_title("Building Windows binaries")
     parts = str(sys.version_info.major), str(sys.version_info.minor)
     ver = ''.join(parts)
diff --git a/scripts/dev/freeze.py b/scripts/dev/freeze.py
index b651dd194..00011afc7 100755
--- a/scripts/dev/freeze.py
+++ b/scripts/dev/freeze.py
@@ -67,6 +67,11 @@ def get_build_exe_options(skip_html=False):
         ('qutebrowser/html', 'html'),
     ]
 
+    if os.path.exists(os.path.join('qutebrowser', '3rdparty', 'pdfjs')):
+        include_files.append(('qutebrowser/3rdparty/pdfjs', '3rdparty/pdfjs'))
+    else:
+        print("Warning: excluding pdfjs as it's not present!")
+
     if not skip_html:
         include_files += [
             ('qutebrowser/html/doc', 'html/doc'),
diff --git a/scripts/dev/misc_checks.py b/scripts/dev/misc_checks.py
index ef32be41d..e629f2152 100644
--- a/scripts/dev/misc_checks.py
+++ b/scripts/dev/misc_checks.py
@@ -96,12 +96,19 @@ def check_spelling():
               '[Ss]tatemachine', '[Mm]etaobject', '[Ll]ogrecord',
               '[Ff]iletype'}
 
+    # Files which should be ignored, e.g. because they come from another
+    # package
+    ignored = [
+        os.path.join('.', 'scripts', 'dev', 'misc_checks.py'),
+        os.path.join('.', 'qutebrowser', '3rdparty', 'pdfjs'),
+    ]
+
     seen = collections.defaultdict(list)
     try:
         ok = True
         for fn in _get_files():
             with tokenize.open(fn) as f:
-                if fn == os.path.join('.', 'scripts', 'dev', 'misc_checks.py'):
+                if any(fn.startswith(i) for i in ignored):
                     continue
                 for line in f:
                     for w in words:
diff --git a/scripts/dev/run_vulture.py b/scripts/dev/run_vulture.py
index 2ee3a776a..db520f924 100755
--- a/scripts/dev/run_vulture.py
+++ b/scripts/dev/run_vulture.py
@@ -89,6 +89,7 @@ def whitelist_generator():
     yield 'qutebrowser.utils.log.VDEBUG'
     yield 'qutebrowser.utils.log.QtWarningFilter.filter'
     yield 'logging.LogRecord.log_color'
+    yield 'qutebrowser.browser.pdfjs.is_available'
     # vulture doesn't notice the hasattr() and thus thinks netrc_used is unused
     # in NetworkManager.on_authentication_required
     yield 'PyQt5.QtNetwork.QNetworkReply.netrc_used'
diff --git a/scripts/dev/update_3rdparty.py b/scripts/dev/update_3rdparty.py
new file mode 100755
index 000000000..6db01bc11
--- /dev/null
+++ b/scripts/dev/update_3rdparty.py
@@ -0,0 +1,64 @@
+#!/usr/bin/env python3
+# vim: ft=python fileencoding=utf-8 sts=4 sw=4 et:
+
+# Copyright 2015 Daniel Schadt
+#
+# This file is part of qutebrowser.
+#
+# qutebrowser is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# qutebrowser is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with qutebrowser.  If not, see <http://www.gnu.org/licenses/>.
+
+"""Update all third-party-modules."""
+
+import urllib.request
+import shutil
+import json
+import os
+
+
+def get_latest_pdfjs_url():
+    """Get the URL of the latest pdf.js prebuilt package.
+
+    Returns a (version, url)-tuple."""
+    github_api = 'https://api.github.com'
+    endpoint = 'repos/mozilla/pdf.js/releases/latest'
+    request_url = '{}/{}'.format(github_api, endpoint)
+    with urllib.request.urlopen(request_url) as fp:
+        data = json.loads(fp.read().decode('utf-8'))
+
+    download_url = data['assets'][0]['browser_download_url']
+    version_name = data['name']
+    return (version_name, download_url)
+
+
+def update_pdfjs():
+    """Download and extract the latest pdf.js version."""
+    version, url = get_latest_pdfjs_url()
+    target_path = os.path.join('qutebrowser', '3rdparty', 'pdfjs')
+    print("=> Downloading pdf.js {}".format(version))
+    (archive_path, _headers) = urllib.request.urlretrieve(url)
+    if os.path.isdir(target_path):
+        print("Removing old version in {}".format(target_path))
+        shutil.rmtree(target_path)
+    os.makedirs(target_path)
+    print("Extracting new version")
+    with open(archive_path, 'rb') as archive:
+        shutil.unpack_archive(archive, target_path, 'zip')
+    urllib.request.urlcleanup()
+
+
+def main():
+    update_pdfjs()
+
+if __name__ == '__main__':
+    main()
diff --git a/tests/integration/data/misc/test.pdf b/tests/integration/data/misc/test.pdf
new file mode 100644
index 000000000..6bd5f16be
--- /dev/null
+++ b/tests/integration/data/misc/test.pdf
diff --git a/tests/integration/features/misc.feature b/tests/integration/features/misc.feature
index 1df5d99a3..b31ef0f67 100644
--- a/tests/integration/features/misc.feature
+++ b/tests/integration/features/misc.feature
@@ -245,3 +245,17 @@ Feature: Various utility commands.
         When I set general -> startpage to http://localhost:(port)/data/numbers/1.txt,http://localhost:(port)/data/numbers/2.txt
         And I run :home
         Then data/numbers/1.txt should be loaded
+
+    # pdfjs support
+
+    Scenario: pdfjs is used for pdf files
+        Given pdfjs is available
+        When I set content -> enable-pdfjs to true
+        And I open data/misc/test.pdf
+        Then the javascript message "PDF * [*] (PDF.js: *)" should be logged
+
+    Scenario: pdfjs is not used when disabled
+        When I set content -> enable-pdfjs to false
+        And I set storage -> prompt-download-directory to false
+        And I open data/misc/test.pdf
+        Then "Download finished" should be logged
diff --git a/tests/integration/features/test_misc.py b/tests/integration/features/test_misc.py
index dc3cebdfa..a19d3c908 100644
--- a/tests/integration/features/test_misc.py
+++ b/tests/integration/features/test_misc.py
@@ -23,10 +23,13 @@ import subprocess
 
 import pytest
 import pytest_bdd as bdd
-bdd.scenarios('misc.feature')
 
 import qutebrowser
 from qutebrowser.utils import docutils
+from qutebrowser.browser import pdfjs
+
+
+bdd.scenarios('misc.feature')
 
 
 @bdd.when("the documentation is up to date")
@@ -51,3 +54,9 @@ def update_documentation():
 
     update_script = os.path.join(script_path, 'asciidoc2html.py')
     subprocess.call([sys.executable, update_script])
+
+
+@bdd.given('pdfjs is available')
+def pdfjs_available():
+    if not pdfjs.is_available():
+        pytest.skip("No pdfjs installation found.")
diff --git a/tests/unit/browser/test_pdfjs.py b/tests/unit/browser/test_pdfjs.py
new file mode 100644
index 000000000..f3bf0413f
--- /dev/null
+++ b/tests/unit/browser/test_pdfjs.py
@@ -0,0 +1,76 @@
+# vim: ft=python fileencoding=utf-8 sts=4 sw=4 et:
+
+# Copyright 2015 Daniel Schadt
+#
+# This file is part of qutebrowser.
+#
+# qutebrowser is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# qutebrowser is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with qutebrowser.  If not, see <http://www.gnu.org/licenses/>.
+
+"""Tests for qutebrowser.browser.pdfjs"""
+
+import textwrap
+
+import pytest
+from PyQt5.QtCore import QUrl
+
+from qutebrowser.browser import pdfjs
+
+
+# Note that we got double protection, once because we use QUrl.FullyEncoded and
+# because we use qutebrowser.browser.webelem.javascript_escape.  Characters
+# like " are already replaced by QUrl.
+@pytest.mark.parametrize('url, expected', [
+    ('http://foo.bar', "http://foo.bar"),
+    ('http://"', ''),
+    ('\0', '%00'),
+    ('http://foobar/");alert("attack!");',
+     'http://foobar/%22);alert(%22attack!%22);'),
+])
+def test_generate_pdfjs_script(url, expected):
+    expected_code = ('PDFJS.verbosity = PDFJS.VERBOSITY_LEVELS.info;\n'
+                     'PDFView.open("{}");\n'.format(expected))
+    url = QUrl(url)
+    actual = pdfjs._generate_pdfjs_script(url)
+    assert actual == expected_code
+
+
+def test_fix_urls():
+    page = textwrap.dedent("""
+        <html>
+        <script src="viewer.js"></script>
+        <link href="viewer.css">
+        <script src="unrelated.js"></script>
+        </html>
+    """).strip()
+
+    expected = textwrap.dedent("""
+        <html>
+        <script src="qute://pdfjs/web/viewer.js"></script>
+        <link href="qute://pdfjs/web/viewer.css">
+        <script src="unrelated.js"></script>
+        </html>
+    """).strip()
+
+    actual = pdfjs.fix_urls(page)
+    assert actual == expected
+
+
+@pytest.mark.parametrize('path, expected', [
+    ('web/viewer.js', 'viewer.js'),
+    ('build/locale/foo.bar', 'locale/foo.bar'),
+    ('viewer.js', 'viewer.js'),
+    ('foo/viewer.css', 'foo/viewer.css'),
+])
+def test_remove_prefix(path, expected):
+    assert pdfjs._remove_prefix(path) == expected
diff --git a/tests/unit/utils/test_version.py b/tests/unit/utils/test_version.py
index 3ad45ce34..f8c1a88e3 100644
--- a/tests/unit/utils/test_version.py
+++ b/tests/unit/utils/test_version.py
@@ -34,6 +34,7 @@ import pytest
 
 import qutebrowser
 from qutebrowser.utils import version
+from qutebrowser.browser import pdfjs
 
 
 class GitStrSubprocessFake:
@@ -529,6 +530,39 @@ class TestOsInfo:
         version._os_info()
 
 
+class TestPDFJSVersion:
+
+    """Tests for _pdfjs_version."""
+
+    def test_not_found(self, mocker):
+        mocker.patch('qutebrowser.utils.version.pdfjs.get_pdfjs_res',
+                     side_effect=pdfjs.PDFJSNotFound)
+        assert version._pdfjs_version() == 'no'
+
+    def test_unknown(self, monkeypatch):
+        monkeypatch.setattr('qutebrowser.utils.version.pdfjs.get_pdfjs_res',
+                            lambda path: b'foobar')
+        assert version._pdfjs_version() == 'unknown'
+
+    def test_known(self, monkeypatch):
+        pdfjs_code = textwrap.dedent("""
+            // Initializing PDFJS global object (if still undefined)
+            if (typeof PDFJS === 'undefined') {
+              (typeof window !== 'undefined' ? window : this).PDFJS = {};
+            }
+
+            PDFJS.version = '1.2.109';
+            PDFJS.build = '875588d';
+
+            (function pdfjsWrapper() {
+              // Use strict in our context only - users might not want it
+              'use strict';
+        """).strip().encode('utf-8')
+        monkeypatch.setattr('qutebrowser.utils.version.pdfjs.get_pdfjs_res',
+                            lambda path: pdfjs_code)
+        assert version._pdfjs_version() == '1.2.109'
+
+
 class FakeQSslSocket:
 
     """Fake for the QSslSocket Qt class.
@@ -571,6 +605,7 @@ def test_version_output(git_commit, harfbuzz, frozen, short, stubs,
         'qVersion': lambda: 'QT RUNTIME VERSION',
         'PYQT_VERSION_STR': 'PYQT VERSION',
         '_module_versions': lambda: ['MODULE VERSION 1', 'MODULE VERSION 2'],
+        '_pdfjs_version': lambda: 'PDFJS VERSION',
         'qWebKitVersion': lambda: 'WEBKIT VERSION',
         'QSslSocket': FakeQSslSocket('SSL VERSION'),
         'platform.platform': lambda: 'PLATFORM',
@@ -613,6 +648,7 @@ def test_version_output(git_commit, harfbuzz, frozen, short, stubs,
             Desktop: DESKTOP
             MODULE VERSION 1
             MODULE VERSION 2
+            pdf.js: PDFJS VERSION
             Webkit: WEBKIT VERSION
             Harfbuzz: {harfbuzz}
             SSL: SSL VERSION