#!/usr/bin/env python3 # qute-gemini - Open Gemini links in qutebrowser and render them as HTML # # SPDX-FileCopyrightText: 2019-2020 solderpunk # SPDX-FileCopyrightText: 2020 Aaron Janse # SPDX-FileCopyrightText: 2020 petedussin # SPDX-FileCopyrightText: 2020-2021 Sotiris Papatheodorou # SPDX-License-Identifier: GPL-3.0-or-later # 2022-2023 Marty Oehme (added stand-alone script capability) # Use it as a qutebrowser userscript to open gemini pages: # Put this file in qutebrowser userscript folder and call command # `:spawn --userscript qute-gemini "gemini://my-gemini-url.org"` # or # `:hint links userscript qute-gemini` to open from selected link # Rename file to `qute-gemini-tab` (or create symlink) to open # any gemini url as a new tab. # Since the script also opens normal URLs you can even replace your # normal link hint mapping with it (usually f or F for tabbed) and # continue surfing like normal, only that you can now also access # any gemini pages as if they were part of the normal http protocol. import cgi import html import os import socket import ssl import sys import tempfile import urllib.parse from typing import Tuple _version = "1.0.0" _max_redirects = 5 _error_page_template = """ Error opening page: URL

qute-gemini error

Error while opening:
URL_TEXT

DESCRIPTION

""" _status_code_desc = { "1": "Gemini status code 1 Input. This is not implemented in qute-gemini.", "10": "Gemini status code 10 Input. This is not implemented in qute-gemini.", "11": """Gemini status code 11 Sensitive Input. This is not implemented in qute-gemini.""", "3": "Gemini status code 3 Redirect. Stopped after " + str(_max_redirects) + " redirects.", "30": "Gemini status code 30 Temporary Redirect. Stopped after " + str(_max_redirects) + " redirects.", "31": "Gemini status code 31 Permanent Redirect. Stopped after " + str(_max_redirects) + " redirects.", "4": "Gemini status code 4 Temporary Failure. Server message: META", "40": "Gemini status code 40 Temporary Failure. Server message: META", "41": """Gemini status code 41 Server Unavailable. The server is unavailable due to overload or maintenance. Server message: META""", "42": """Gemini status code 42 CGI Error. A CGI process, or similar system for generating dynamic content, died unexpectedly or timed out. Server message: META""", "43": """Gemini status code 43 Proxy Error. A proxy request failed because the server was unable to successfully complete a transaction with the remote host. Server message: META""", "44": """Gemini status code 44 Slow Down. Rate limiting is in effect. Please wait META seconds before making another request to this server.""", "5": "Gemini status code 5 Permanent Failure. Server message: META", "50": "Gemini status code 50 Permanent Failure. Server message: META", "51": """Gemini status code 51 Not Found. The requested resource could not be found but may be available in the future. Server message: META""", "52": """Gemini status code 52 Gone. The resource requested is no longer available and will not be available again. Server message: META""", "53": """Gemini status code 53 Proxy Request Refused. The request was for a resource at a domain not served by the server and the server does not accept proxy requests. Server message: META""", "59": """Gemini status code 59 Bad Request. The server was unable to parse the client's request, presumably due to a malformed request. Server message: META""", "6": """Gemini status code 6 Client Certificate Required. This is not implemented in qute-gemini.""", } def qute_url() -> str: """Get the URL passed to the script by qutebrowser.""" return os.environ.get("QUTE_URL", "") def qute_fifo() -> str: """Get the FIFO or file to write qutebrowser commands to.""" return os.environ.get("QUTE_FIFO", "") def html_href(url: str, description: str) -> str: return "".join(['', description, ""]) def qute_gemini_css_path() -> str: """Return the path where the custom CSS file is expected to be.""" try: base_dir = os.environ["XDG_DATA_HOME"] except KeyError: base_dir = os.path.join(os.environ["HOME"], ".local/share") return os.path.join(base_dir, "qutebrowser/userscripts/qute-gemini.css") def gemini_absolutise_url(base_url: str, relative_url: str) -> str: """Absolutise relative gemini URLs. Adapted from gcat: https://github.com/aaronjanse/gcat """ if "://" not in relative_url: # Python's URL tools somehow only work with known schemes? base_url = base_url.replace("gemini://", "http://") relative_url = urllib.parse.urljoin(base_url, relative_url) relative_url = relative_url.replace("http://", "gemini://") return relative_url def gemini_fetch_url(url: str) -> Tuple[str, str, str, str, str]: """Fetch a Gemini URL and return the content as a string. url: URL with gemini:// or no scheme. Returns 4 strings: the content, the URL the content was fetched from, the Gemini status code, the value of the meta field and an error message. Adapted from gcat: https://github.com/aaronjanse/gcat """ # Parse the URL to get the hostname and port parsed_url = urllib.parse.urlparse(url) if not parsed_url.scheme: url = "gemini://" + url parsed_url = urllib.parse.urlparse(url) if parsed_url.scheme != "gemini": return "", "Received non-gemini:// URL: " + url, "59", "", "Non-gemini URL" if parsed_url.port is not None: useport = parsed_url.port else: useport = 1965 # Do the Gemini transaction, looping for redirects redirects = 0 while True: # Send the request s = socket.create_connection((parsed_url.hostname, useport)) context = ssl.SSLContext(ssl.PROTOCOL_TLS) context.check_hostname = False context.verify_mode = ssl.CERT_NONE s = context.wrap_socket(s, server_hostname=parsed_url.netloc) s.sendall((url + "\r\n").encode("UTF-8")) # Get the status code and meta fp = s.makefile("rb") header = fp.readline().decode("UTF-8").strip() status, meta = header.split()[:2] # Follow up to 5 redirects if status.startswith("3"): url = gemini_absolutise_url(url, meta) parsed_url = urllib.parse.urlparse(url) redirects += 1 if redirects > _max_redirects: # Too many redirects break # Otherwise we're done else: break # Process the response content = "" error_msg = "" # 2x Success if status.startswith("2"): media_type, media_type_opts = cgi.parse_header(meta) # Decode according to declared charset defaulting to UTF-8 if meta.startswith("text/gemini"): charset = media_type_opts.get("charset", "UTF-8") content = fp.read().decode(charset) else: error_msg = "Expected media type text/gemini but received " + media_type # Handle errors else: # Try matching a 2-digit and then a 1-digit status code try: error_msg = _status_code_desc[status[0:2]] except KeyError: try: error_msg = _status_code_desc[status[0]] except KeyError: error_msg = "The server sent back something weird." # Substitute the contents of meta into the error message if needed error_msg = error_msg.replace("META", meta) return content, url, status, meta, error_msg def gemtext_to_html( gemtext: str, url: str, original_url: str, status: str, meta: str ) -> str: """Convert gemtext to HTML. title: Used as the document title. url: The URL the gemtext was received from. Used to resolve relative URLs in the gemtext content. original_url: The URL the original request was made at. status: The Gemini status code returned by the server. meta: The meta returned by the server. Returns the HTML representation as a string. """ # Accumulate converted gemtext lines lines = [ '', '', "\t", "\t\t" + html.escape(url) + "", "\t\t", "\t", "\t", "\t

", ] in_pre = False in_list = False # Add an extra newline to ensure list tags are closed properly for line in (gemtext + "\n").splitlines(): # Add the list closing tag if not line.startswith("*") and in_list: lines.append("\t\t") in_list = False # Blank line, ignore if not line: pass # Link elif line.startswith("=>"): ln = line[2:].split(None, 1) # Use the URL itself as the description if there is none if len(ln) == 1: ln.append(ln[0]) # Encode the link description ln[1] = html.escape(ln[1]) # Resolve relative URLs ln[0] = gemini_absolutise_url(url, ln[0]) lines.append("\t\t

" + html_href(ln[0], ln[1]) + "

") # Preformated toggle elif line.startswith("```"): if in_pre: lines.append("\t\t") else: lines.append("\t\t

")
            in_pre = not in_pre
        # Preformated
        elif in_pre:
            lines.append(line)
        # Header
        elif line.startswith("###"):
            lines.append("\t\t" + html.escape(line[3:].strip()) + "")
        elif line.startswith("##"):
            lines.append("\t\t" + html.escape(line[2:].strip()) + "")
        elif line.startswith("#"):
            lines.append("\t\t" + html.escape(line[1:].strip()) + "")
        # List
        elif line.startswith("*"):
            if not in_list:
                lines.append("\t\t")
            in_list = True
            lines.append("\t\t\t" + html.escape(line[1:].strip()) + "")
        # Quote
        elif line.startswith(">"):
            lines.extend(
                [
                    "\t\t",
                    "\t\t\t" + line[1:].strip() + "",
                    "\t\t",
                ]
            )
        # Normal text
        else:
            lines.append("\t\t" + html.escape(line.strip()) + "")
    url_html = html_href(url, html.escape(url))
    original_url_html = html_href(original_url, html.escape(original_url))
    lines.extend(
        [
            "",
            "\t

", "\t

", "\t\t

", "\t\t\tContent from " + url_html, "\t\t

", "\t\t

Original URL: " + original_url_html + "
Status: " + status + "
Meta: " + meta + "
Fetched by: qute-gemini ' + str(_version) + "

", "\t

", "\t", "", ] ) return "\n".join(lines) def get_css() -> str: # Search for qute-gemini.css in the directory this script is located in css_file = qute_gemini_css_path() if os.path.isfile(css_file): # Return the file contents with open(css_file, "r") as f: return f.read().strip() else: # Use no CSS return "" def qute_error_page(url: str, description: str) -> str: """Return a data URI error page like qutebrowser does. url: The URL of the page that failed to load. description: A description of the error. Returns a data URI containing the error page. """ # Generate the HTML error page html_page = _error_page_template.replace("URL", url) html_page = html_page.replace("URL_TEXT", html.escape(url)) html_page = html_page.replace("DESCRIPTION", html.escape(description)) html_page = html_page.replace("CSS", get_css()) # URL encode and return as a data URI return "data:text/html;charset=UTF-8," + urllib.parse.quote(html_page) def open_gemini(url: str) -> str: """Open Gemini URL in qutebrowser.""" # Get the Gemini content content, content_url, status, meta, error_msg = gemini_fetch_url(url) if error_msg: # Generate an error page in a data URI open_url = qute_error_page(url, error_msg) else: # Success, convert to HTML in a temporary file tmpf = tempfile.NamedTemporaryFile("w", suffix=".html", delete=False) tmp_filename = tmpf.name tmpf.close() if not tmp_filename: return "" with open(tmp_filename, "w") as f: f.write(gemtext_to_html(content, content_url, url, status, meta)) open_url = " file://" + tmp_filename # Open the HTML file in qutebrowser return open_url def open_url(url: str, open_args: str) -> None: parsed_url = urllib.parse.urlparse(url) if parsed_url.scheme == "gemini": to_open = open_gemini(url) else: to_open = url if not to_open: return fifo = qute_fifo() if fifo and fifo != "": with open(fifo, "w") as qfifo: qfifo.write(f"open {open_args} {to_open}") return os.system(f"xdg-open {to_open}") if __name__ == "__main__": # Open in the current or a new tab depending on the script name if sys.argv[0].endswith("-tab"): open_args = "-b -r" else: open_args = "" # Take url to open as argument or from qutebrowser url if len(sys.argv) > 1: url = sys.argv[1] else: url = qute_url() # Select how to open the URL depending on its scheme open_url(url, open_args)