doc/gendoc.py

sslutil: improve messaging around unsupported protocols (issue5303)

There are various causes for the inability to negotiate common SSL/TLS
protocol between client and server. Previously, we had a single, not
very actionable warning message for all of them.

As people encountered TLS 1.0 servers in real life, it was quickly
obvious that the existing messaging was inadequate to help users
rectify the situation.

This patch makes the warning messages much more verbose in hopes of
making them more actionable while simultaneously encouraging users
and servers to adopt better security practices.

This messaging flirts with the anti-pattern of "never blame the
user" by signaling out poorly-configured servers. But if we're going to
disallow TLS 1.0 by default, I think we need to say *something* or
people are just going to blame Mercurial for not being able to connect.
The messaging tries to exonerate Mercurial from being the at fault
party by pointing out the server is the entity that doesn't support
proper security (when appropriate, of course).

#!/usr/bin/env python
"""usage: %s DOC ...

where DOC is the name of a document
"""

from __future__ import absolute_import

import os
import sys
import textwrap

# This script is executed during installs and may not have C extensions
# available. Relax C module requirements.
os.environ['HGMODULEPOLICY'] = 'allow'
# import from the live mercurial repo
sys.path.insert(0, "..")
from mercurial import demandimport; demandimport.enable()
from mercurial import (
    commands,
    extensions,
    help,
    minirst,
    ui as uimod,
)
from mercurial.i18n import (
    gettext,
    _,
)

table = commands.table
globalopts = commands.globalopts
helptable = help.helptable
loaddoc = help.loaddoc

def get_desc(docstr):
    if not docstr:
        return "", ""
    # sanitize
    docstr = docstr.strip("\n")
    docstr = docstr.rstrip()
    shortdesc = docstr.splitlines()[0].strip()

    i = docstr.find("\n")
    if i != -1:
        desc = docstr[i + 2:]
    else:
        desc = shortdesc

    desc = textwrap.dedent(desc)

    return (shortdesc, desc)

def get_opts(opts):
    for opt in opts:
        if len(opt) == 5:
            shortopt, longopt, default, desc, optlabel = opt
        else:
            shortopt, longopt, default, desc = opt
            optlabel = _("VALUE")
        allopts = []
        if shortopt:
            allopts.append("-%s" % shortopt)
        if longopt:
            allopts.append("--%s" % longopt)
        if isinstance(default, list):
            allopts[-1] += " <%s[+]>" % optlabel
        elif (default is not None) and not isinstance(default, bool):
            allopts[-1] += " <%s>" % optlabel
        if '\n' in desc:
            # only remove line breaks and indentation
            desc = ' '.join(l.lstrip() for l in desc.split('\n'))
        desc += default and _(" (default: %s)") % default or ""
        yield (", ".join(allopts), desc)

def get_cmd(cmd, cmdtable):
    d = {}
    attr = cmdtable[cmd]
    cmds = cmd.lstrip("^").split("|")

    d['cmd'] = cmds[0]
    d['aliases'] = cmd.split("|")[1:]
    d['desc'] = get_desc(gettext(attr[0].__doc__))
    d['opts'] = list(get_opts(attr[1]))

    s = 'hg ' + cmds[0]
    if len(attr) > 2:
        if not attr[2].startswith('hg'):
            s += ' ' + attr[2]
        else:
            s = attr[2]
    d['synopsis'] = s.strip()

    return d

def showdoc(ui):
    # print options
    ui.write(minirst.section(_("Options")))
    multioccur = False
    for optstr, desc in get_opts(globalopts):
        ui.write("%s\n    %s\n\n" % (optstr, desc))
        if optstr.endswith("[+]>"):
            multioccur = True
    if multioccur:
        ui.write(_("\n[+] marked option can be specified multiple times\n"))
        ui.write("\n")

    # print cmds
    ui.write(minirst.section(_("Commands")))
    commandprinter(ui, table, minirst.subsection)

    # print help topics
    # The config help topic is included in the hgrc.5 man page.
    helpprinter(ui, helptable, minirst.section, exclude=['config'])

    ui.write(minirst.section(_("Extensions")))
    ui.write(_("This section contains help for extensions that are "
               "distributed together with Mercurial. Help for other "
               "extensions is available in the help system."))
    ui.write(("\n\n"
             ".. contents::\n"
             "   :class: htmlonly\n"
             "   :local:\n"
             "   :depth: 1\n\n"))

    for extensionname in sorted(allextensionnames()):
        mod = extensions.load(ui, extensionname, None)
        ui.write(minirst.subsection(extensionname))
        ui.write("%s\n\n" % gettext(mod.__doc__))
        cmdtable = getattr(mod, 'cmdtable', None)
        if cmdtable:
            ui.write(minirst.subsubsection(_('Commands')))
            commandprinter(ui, cmdtable, minirst.subsubsubsection)

def showtopic(ui, topic):
    extrahelptable = [
        (["common"], '', loaddoc('common')),
        (["hg.1"], '', loaddoc('hg.1')),
        (["hg-ssh.8"], '', loaddoc('hg-ssh.8')),
        (["hgignore.5"], '', loaddoc('hgignore.5')),
        (["hgrc.5"], '', loaddoc('hgrc.5')),
        (["hgignore.5.gendoc"], '', loaddoc('hgignore')),
        (["hgrc.5.gendoc"], '', loaddoc('config')),
    ]
    helpprinter(ui, helptable + extrahelptable, None, include=[topic])

def helpprinter(ui, helptable, sectionfunc, include=[], exclude=[]):
    for names, sec, doc in helptable:
        if exclude and names[0] in exclude:
            continue
        if include and names[0] not in include:
            continue
        for name in names:
            ui.write(".. _%s:\n" % name)
        ui.write("\n")
        if sectionfunc:
            ui.write(sectionfunc(sec))
        if callable(doc):
            doc = doc(ui)
        ui.write(doc)
        ui.write("\n")

def commandprinter(ui, cmdtable, sectionfunc):
    h = {}
    for c, attr in cmdtable.items():
        f = c.split("|")[0]
        f = f.lstrip("^")
        h[f] = c
    cmds = h.keys()
    cmds.sort()

    for f in cmds:
        if f.startswith("debug"):
            continue
        d = get_cmd(h[f], cmdtable)
        ui.write(sectionfunc(d['cmd']))
        # short description
        ui.write(d['desc'][0])
        # synopsis
        ui.write("::\n\n")
        synopsislines = d['synopsis'].splitlines()
        for line in synopsislines:
            # some commands (such as rebase) have a multi-line
            # synopsis
            ui.write("   %s\n" % line)
        ui.write('\n')
        # description
        ui.write("%s\n\n" % d['desc'][1])
        # options
        opt_output = list(d['opts'])
        if opt_output:
            opts_len = max([len(line[0]) for line in opt_output])
            ui.write(_("Options:\n\n"))
            multioccur = False
            for optstr, desc in opt_output:
                if desc:
                    s = "%-*s  %s" % (opts_len, optstr, desc)
                else:
                    s = optstr
                ui.write("%s\n" % s)
                if optstr.endswith("[+]>"):
                    multioccur = True
            if multioccur:
                ui.write(_("\n[+] marked option can be specified"
                           " multiple times\n"))
            ui.write("\n")
        # aliases
        if d['aliases']:
            ui.write(_("    aliases: %s\n\n") % " ".join(d['aliases']))


def allextensionnames():
    return extensions.enabled().keys() + extensions.disabled().keys()

if __name__ == "__main__":
    doc = 'hg.1.gendoc'
    if len(sys.argv) > 1:
        doc = sys.argv[1]

    ui = uimod.ui()
    if doc == 'hg.1.gendoc':
        showdoc(ui)
    else:
        showtopic(ui, sys.argv[1])