#!/usr/bin/env python3 # Copyright 2015 The Chromium Authors. All rights reserved. # Use of this source code is governed by a BSD-style license that can be # found in the LICENSE file. """Simple Markdown browser for a Git checkout.""" import http.server import socketserver import argparse import codecs import html import os import re import socket import sys import threading import time import urllib.request, urllib.parse, urllib.error import webbrowser from xml.etree import ElementTree THIS_DIR = os.path.realpath(os.path.dirname(__file__)) SRC_DIR = os.path.dirname(os.path.dirname(THIS_DIR)) sys.path.insert(0, os.path.join(SRC_DIR, 'third_party', 'Python-Markdown')) import markdown def main(argv): parser = argparse.ArgumentParser(prog='md_browser') parser.add_argument('-p', '--port', type=int, default=8080, help='port to run on (default = %(default)s)') parser.add_argument('-d', '--directory', type=str, default=SRC_DIR) parser.add_argument('-e', '--external', action='store_true', help='whether to bind to external port') parser.add_argument('file', nargs='?', help='open file in browser') args = parser.parse_args(argv) top_level = os.path.realpath(args.directory) hostname = '0.0.0.0' if args.external else 'localhost' server_address = (hostname, args.port) s = Server(server_address, top_level) origin = 'http://' + hostname if args.port != 80: origin += ':%s' % args.port print('Listening on %s/' % origin) thread = None if args.file: path = os.path.realpath(args.file) if not path.startswith(top_level): print('%s is not under %s' % (args.file, args.directory)) return 1 rpath = os.path.relpath(path, top_level) url = '%s/%s' % (origin, rpath) print('Opening %s' % url) thread = threading.Thread(target=_open_url, args=(url,)) thread.start() elif os.path.isfile(os.path.join(top_level, 'docs', 'README.md')): print(' Try loading %s/docs/README.md' % origin) elif os.path.isfile(os.path.join(args.directory, 'README.md')): print(' Try loading %s/README.md' % origin) retcode = 1 try: s.serve_forever() except KeyboardInterrupt: retcode = 130 except Exception as e: print('Exception raised: %s' % str(e)) s.shutdown() if thread: thread.join() return retcode def _open_url(url): time.sleep(1) webbrowser.open(url) def _gitiles_slugify(value, _separator): """Convert a string (representing a section title) to URL anchor name. This function is passed to "toc" extension as an extension option, so we can emulate the way how Gitiles converts header titles to URL anchors. Gitiles' official documentation about the conversion is at: https://gerrit.googlesource.com/gitiles/+/master/Documentation/markdown.md#Named-anchors Args: value: The name of a section that is to be converted. _separator: Unused. This is actually a configurable string that is used as a replacement character for spaces in the title, typically set to '-'. Since we emulate Gitiles' way of slugification here, it makes little sense to have the separator charactor configurable. """ # TODO(yutak): Implement accent removal. This does not seem easy without # some library. For now we just make accented characters turn into # underscores, just like other non-ASCII characters. def decode_escaped_chars(regex_match): # Python-Markdown encodes escaped sequences (ex. "\_") as "\x02 (integer # ascii code) \x03". We decode the integer ascii code to align with Gitiles # behavior (ex. 95 -> '_'). return chr(int(regex_match.group(1))) # Non-ASCII turns into '?'. value = value.encode('ascii', 'replace').decode('ascii') value = re.sub('\x02(\\d+)\x03', decode_escaped_chars, value) value = re.sub(r'[^- a-zA-Z0-9]', '_', value) # Non-alphanumerics to '_'. value = value.replace(' ', '-') value = re.sub(r'([-_])[-_]+', r'\1', value) # Fold hyphens and underscores. return value class Server(socketserver.TCPServer): def __init__(self, server_address, top_level): socketserver.TCPServer.__init__(self, server_address, Handler) self.top_level = top_level def server_bind(self): self.socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1) self.socket.bind(self.server_address) class Handler(http.server.SimpleHTTPRequestHandler): def do_GET(self): self.path = urllib.parse.unquote(self.path) path = self.path # strip off the repo and branch info, if present, for compatibility # with gitiles. if path.startswith('/chromium/src/+/master'): path = path[len('/chromium/src/+/master'):] full_path = os.path.normpath(os.path.join(self.server.top_level, path[1:])) if not full_path.startswith(self.server.top_level): self._DoUnknown() elif path in ('/base.css', '/doc.css', '/prettify.css'): self._DoCSS(path[1:]) elif not os.path.exists(full_path): self._DoNotFound() elif path.lower().endswith('.md'): self._DoMD(path) elif os.path.exists(full_path + '/README.md'): separator = '/' if path.endswith('/'): separator = '' self._DoMD(path + separator + 'README.md') elif path.lower().endswith('.png'): self._DoImage(full_path, 'image/png') elif path.lower().endswith('.jpg'): self._DoImage(full_path, 'image/jpeg') elif path.lower().endswith('.svg'): self._DoImage(full_path, 'image/svg+xml') elif os.path.isdir(full_path): self._DoDirListing(full_path) elif os.path.exists(full_path): self._DoRawSourceFile(full_path) else: self._DoUnknown() def _DoMD(self, path): extensions = [ 'markdown.extensions.def_list', 'markdown.extensions.fenced_code', 'markdown.extensions.tables', 'markdown.extensions.toc', 'gitiles_autolink', 'gitiles_ext_blocks', 'gitiles_smart_quotes', ] extension_configs = { 'markdown.extensions.toc': { 'slugify': _gitiles_slugify }, } contents = self._Read(path[1:]) md = markdown.Markdown(extensions=extensions, extension_configs=extension_configs, tab_length=4, output_format='html4') has_a_single_h1 = (len([line for line in contents.splitlines() if (line.startswith('#') and not line.startswith('##'))]) == 1) md.treeprocessors.register(_AdjustTOC(has_a_single_h1), 'adjust_toc', 4) md_fragment = md.convert(contents) try: self._WriteHeader('text/html') self._WriteTemplate('header.html') self._Write('
') self._Write(md_fragment) self._Write('
') self._WriteTemplate('footer.html') except: raise def _DoRawSourceFile(self, full_path): self._WriteHeader('text/html') self._WriteTemplate('header.html') self._Write('') with open(full_path) as fp: # Escape html over the entire file at once. data = fp.read().replace( '&', '&').replace( '<', '<').replace( '>', '>').replace( '"', '"') for i, line in enumerate(data.splitlines(), start=1): self._Write( ('' '' '') % { 'num': i, 'quot': "'", 'line': line }) self._Write('
' '' '%(num)s%(line)s
') self._WriteTemplate('footer.html') def _DoCSS(self, template): self._WriteHeader('text/css') self._WriteTemplate(template) def _DoNotFound(self): self._WriteHeader('text/html', status_code=404) self._Write('%s not found' % html.escape(self.path)) def _DoUnknown(self): self._WriteHeader('text/html', status_code=501) self._Write('I do not know how to serve %s.' '' % html.escape(self.path)) def _DoDirListing(self, full_path): self._WriteHeader('text/html') self._WriteTemplate('header.html') self._Write('
') self._Write('\n') escaped_dir = html.escape(self.path.rstrip('/'), quote=True) for _, dirs, files in os.walk(full_path): for f in sorted(files): if f.startswith('.'): continue f = html.escape(f, quote=True) if f.endswith('.md'): bold = ('', '') else: bold = ('', '') self._Write('%s%s%s
\n' % (escaped_dir, f, bold[0], f, bold[1])) self._Write('
\n') for d in sorted(dirs): if d.startswith('.'): continue d = html.escape(d, quote=True) self._Write('%s/
\n' % (escaped_dir, d, d)) break self._Write('
') self._WriteTemplate('footer.html') def _DoImage(self, full_path, mime_type): self._WriteHeader(mime_type) with open(full_path, 'rb') as f: self.wfile.write(f.read()) def _Read(self, relpath, relative_to=None): if relative_to is None: relative_to = self.server.top_level assert not relpath.startswith(os.sep) path = os.path.join(relative_to, relpath) with codecs.open(path, encoding='utf-8') as fp: return fp.read() def _Write(self, contents): self.wfile.write(contents.encode('utf-8')) def _WriteHeader(self, content_type='text/plain', status_code=200): self.send_response(status_code) self.send_header('Content-Type', content_type) self.end_headers() def _WriteTemplate(self, template): contents = self._Read(os.path.join('tools', 'md_browser', template), relative_to=SRC_DIR) self._Write(contents) class _AdjustTOC(markdown.treeprocessors.Treeprocessor): def __init__(self, has_a_single_h1): super(_AdjustTOC, self).__init__() self.has_a_single_h1 = has_a_single_h1 def run(self, tree): # Given # # # H1 # # [TOC] # # ## first H2 # # ## second H2 # # the markdown.extensions.toc extension generates: # #
#
# # for [TOC]. But, we want the TOC to have its own subheading, so # we rewrite
to: # #
#

Contents

#
#
# # In addition, if the document only has a single H1, it is usually the # title, and we don't want the title to be in the TOC. So, we remove it # and shift all of the title's children up a level, leaving: # #
#

Contents

#
#
for toc_node in tree.findall(".//*[@class='toc']"): toc_ul = toc_node[0] if self.has_a_single_h1: toc_ul_li = toc_ul[0] ul_with_the_desired_toc_entries = toc_ul_li[1] else: ul_with_the_desired_toc_entries = toc_ul toc_node.remove(toc_ul) contents = ElementTree.SubElement(toc_node, 'h2') contents.text = 'Contents' contents.tail = '\n' toc_aux = ElementTree.SubElement(toc_node, 'div', {'class': 'toc-aux'}) toc_aux.text = '\n' toc_aux.append(ul_with_the_desired_toc_entries) toc_aux.tail = '\n' if __name__ == '__main__': sys.exit(main(sys.argv[1:]))