From 0f1a2cbe434cba243ce65ff43a88722c2bcf6f2c Mon Sep 17 00:00:00 2001 From: Joshua Harlow Date: Thu, 11 Oct 2012 12:49:45 -0700 Subject: More adjustments/cleanups for the system configuration helper objects. 1. Add in a parser for the /etc/hostname file that can be shared 2. Adjust the sysconfig configobj parser to not always quote fields that it does not need to quote + add in tests around this to ensure that we don't go nuts with quoting again. --- cloudinit/distros/parsers/hostname.py | 90 +++++++++++++++++++++++++++++++ cloudinit/distros/parsers/hosts.py | 3 +- cloudinit/distros/parsers/quoting_conf.py | 80 --------------------------- cloudinit/distros/parsers/sys_conf.py | 85 +++++++++++++++++++++++++++++ 4 files changed, 177 insertions(+), 81 deletions(-) create mode 100644 cloudinit/distros/parsers/hostname.py delete mode 100644 cloudinit/distros/parsers/quoting_conf.py create mode 100644 cloudinit/distros/parsers/sys_conf.py (limited to 'cloudinit/distros/parsers') diff --git a/cloudinit/distros/parsers/hostname.py b/cloudinit/distros/parsers/hostname.py new file mode 100644 index 00000000..7e19f017 --- /dev/null +++ b/cloudinit/distros/parsers/hostname.py @@ -0,0 +1,90 @@ +# vi: ts=4 expandtab +# +# Copyright (C) 2012 Yahoo! Inc. +# +# Author: Joshua Harlow +# +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU General Public License version 3, as +# published by the Free Software Foundation. +# +# This program 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 this program. If not, see . + +from StringIO import StringIO + +from cloudinit.distros.parsers import chop_comment + + +# Parser that knows how to work with /etc/hostname format +class HostnameConf(object): + def __init__(self, text): + self._text = text + self._contents = None + + def parse(self): + if self._contents is None: + self._contents = self._parse(self._text) + + def __str__(self): + self.parse() + contents = StringIO() + for (line_type, components) in self._contents: + if line_type == 'blank': + contents.write("%s\n" % (components[0])) + elif line_type == 'all_comment': + contents.write("%s\n" % (components[0])) + elif line_type == 'hostname': + (hostname, tail) = components + contents.write("%s%s\n" % (hostname, tail)) + # Ensure trailing newline + contents = contents.getvalue() + if not contents.endswith("\n"): + contents += "\n" + return contents + + @property + def hostname(self): + self.parse() + for (line_type, components) in self._contents: + if line_type == 'hostname': + return components[0] + return None + + def set_hostname(self, your_hostname): + your_hostname = your_hostname.strip() + if not your_hostname: + return + self.parse() + replaced = False + for (line_type, components) in self._contents: + if line_type == 'hostname': + components[0] = str(your_hostname) + replaced = True + if not replaced: + self._contents.append(('hostname', [str(your_hostname), ''])) + + def _parse(self, contents): + entries = [] + hostnames_found = set() + for line in contents.splitlines(): + if not len(line.strip()): + entries.append(('blank', [line])) + continue + (head, tail) = chop_comment(line.strip(), '#') + if not len(head): + entries.append(('all_comment', [line])) + continue + entries.append(('hostname', [head, tail])) + hostnames_found.add(head) + if len(hostnames_found) > 1: + raise IOError("Multiple hostnames (%s) found!" + % (hostnames_found)) + return entries + + diff --git a/cloudinit/distros/parsers/hosts.py b/cloudinit/distros/parsers/hosts.py index 5374ab0b..958a7c31 100644 --- a/cloudinit/distros/parsers/hosts.py +++ b/cloudinit/distros/parsers/hosts.py @@ -23,6 +23,7 @@ from cloudinit.distros.parsers import chop_comment # See: man hosts # or http://unixhelp.ed.ac.uk/CGI/man-cgi?hosts +# or http://tinyurl.com/6lmox3 class HostsConf(object): def __init__(self, text): self._text = text @@ -80,7 +81,7 @@ class HostsConf(object): contents = StringIO() for (line_type, components) in self._contents: if line_type == 'blank': - contents.write("%s\n") + contents.write("%s\n" % (components[0])) elif line_type == 'all_comment': contents.write("%s\n" % (components[0])) elif line_type == 'option': diff --git a/cloudinit/distros/parsers/quoting_conf.py b/cloudinit/distros/parsers/quoting_conf.py deleted file mode 100644 index 953ccfe9..00000000 --- a/cloudinit/distros/parsers/quoting_conf.py +++ /dev/null @@ -1,80 +0,0 @@ -# vi: ts=4 expandtab -# -# Copyright (C) 2012 Yahoo! Inc. -# -# Author: Joshua Harlow -# -# This program is free software: you can redistribute it and/or modify -# it under the terms of the GNU General Public License version 3, as -# published by the Free Software Foundation. -# -# This program 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 this program. If not, see . - -# This library is used to parse/write -# out the various sysconfig files edited -# -# It has to be slightly modified though -# to ensure that all values are quoted -# since these configs are usually sourced into -# bash scripts... -from configobj import ConfigObj - -# See: http://tiny.cc/oezbgw -D_QUOTE_CHARS = { - "\"": "\\\"", - "(": "\\(", - ")": "\\)", - "$": '\$', - '`': '\`', -} - -# This class helps adjust the configobj -# writing to ensure that when writing a k/v -# on a line, that they are properly quoted -# and have no spaces between the '=' sign. -# - This is mainly due to the fact that -# the sysconfig scripts are often sourced -# directly into bash/shell scripts so ensure -# that it works for those types of use cases. -class QuotingConfigObj(ConfigObj): - def __init__(self, lines): - ConfigObj.__init__(self, lines, - interpolation=False, - write_empty_values=True) - - def _quote_posix(self, text): - if not text: - return '' - for (k, v) in D_QUOTE_CHARS.iteritems(): - text = text.replace(k, v) - return '"%s"' % (text) - - def _quote_special(self, text): - if text.lower() in ['yes', 'no', 'true', 'false']: - return text - else: - return self._quote_posix(text) - - def _write_line(self, indent_string, entry, this_entry, comment): - # Ensure it is formatted fine for - # how these sysconfig scripts are used - val = self._decode_element(self._quote(this_entry)) - # Single quoted strings should - # always work. - if not val.startswith("'"): - # Perform any special quoting - val = self._quote_special(val) - key = self._decode_element(self._quote(entry, multiline=False)) - cmnt = self._decode_element(comment) - return '%s%s%s%s%s' % (indent_string, - key, - "=", - val, - cmnt) - diff --git a/cloudinit/distros/parsers/sys_conf.py b/cloudinit/distros/parsers/sys_conf.py new file mode 100644 index 00000000..3d8802b8 --- /dev/null +++ b/cloudinit/distros/parsers/sys_conf.py @@ -0,0 +1,85 @@ +# vi: ts=4 expandtab +# +# Copyright (C) 2012 Yahoo! Inc. +# +# Author: Joshua Harlow +# +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU General Public License version 3, as +# published by the Free Software Foundation. +# +# This program 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 this program. If not, see . + +from StringIO import StringIO + +import re + +# This library is used to parse/write +# out the various sysconfig files edited +# +# It has to be slightly modified though +# to ensure that all values are quoted/unquoted correctly +# since these configs are usually sourced into +# bash scripts... +import configobj + + +class SysConf(configobj.ConfigObj): + def __init__(self, contents): + configobj.ConfigObj.__init__(self, contents, + interpolation=False, + write_empty_values=True) + + def __str__(self): + contents = self.write() + out_contents = StringIO() + if isinstance(contents, (list, tuple)): + out_contents.write("\n".join(contents)) + else: + out_contents.write(str(contents)) + return out_contents.getvalue() + + def _quote(self, value, multiline=False): + if not isinstance(value, (str, basestring)): + raise ValueError('Value "%s" is not a string' % (value)) + if len(value) == 0: + return '' + if re.search(r"[\n\r]", value): + raise ValueError('Value "%s" cannot be safely quoted.' % (value)) + quot = "%s" + if '#' in value: + quot = self._get_single_quote(value) + elif value[0] in ['"', "'"] and value[-1] in ['"', "'"]: + # Already quoted, leave it be + pass + elif "'" in value and '"' in value: + quot = self._get_triple_quote(value) + else: + # Quote whitespace if it isn't the start+end of a shell command + white_space_ok = False + if value.strip().startswith("$(") and value.strip().endswith(")"): + white_space_ok = True + if re.search(r"[\t ]", value) and not white_space_ok: + quot = self._get_single_quote(value) + return quot % (value) + + def _write_line(self, indent_string, entry, this_entry, comment): + # Ensure it is formatted fine for + # how these sysconfig scripts are used + if this_entry.startswith("'") or this_entry.startswith('"'): + val = this_entry + val = self._decode_element(self._quote(this_entry)) + key = self._decode_element(self._quote(entry)) + cmnt = self._decode_element(comment) + return '%s%s%s%s%s' % (indent_string, + key, + self._a_to_u('='), + val, + cmnt) + -- cgit v1.2.3