diff options
| -rw-r--r-- | cloudinit/distros/__init__.py | 69 | ||||
| -rw-r--r-- | cloudinit/distros/helpers.py | 96 |
2 files changed, 118 insertions, 47 deletions
diff --git a/cloudinit/distros/__init__.py b/cloudinit/distros/__init__.py index 3e9d934d..bf4317f1 100644 --- a/cloudinit/distros/__init__.py +++ b/cloudinit/distros/__init__.py @@ -34,6 +34,8 @@ from cloudinit import log as logging from cloudinit import ssh_util from cloudinit import util +from cloudinit.distros import helpers + # TODO(harlowja): Make this via config?? IFACE_ACTIONS = { 'up': ['ifup', '--all'], @@ -152,42 +154,43 @@ class Distro(object): return "127.0.0.1" def update_etc_hosts(self, hostname, fqdn): - # Format defined at - # http://unixhelp.ed.ac.uk/CGI/man-cgi?hosts - header = "# Added by cloud-init" - real_header = "%s on %s" % (header, util.time_rfc2822()) + header = '' + if os.path.exists('/etc/hosts'): + eh = helpers.HostsConf(util.load_file("/etc/hosts")) + else: + eh = helpers.HostsConf('') + header = "# Added by cloud-init" + header = "%s on %s" % (header, util.time_rfc2822()) local_ip = self._get_localhost_ip() - hosts_line = "%s\t%s %s" % (local_ip, fqdn, hostname) - new_etchosts = StringIO() - need_write = False - need_change = True - hosts_ro_fn = self._paths.join(True, "/etc/hosts") - for line in util.load_file(hosts_ro_fn).splitlines(): - if line.strip().startswith(header): - continue - if not line.strip() or line.strip().startswith("#"): - new_etchosts.write("%s\n" % (line)) - continue - split_line = [s.strip() for s in line.split()] - if len(split_line) < 2: - new_etchosts.write("%s\n" % (line)) - continue - (ip, hosts) = split_line[0], split_line[1:] - if ip == local_ip: - if sorted([hostname, fqdn]) == sorted(hosts): - need_change = False - if need_change: - line = "%s\n%s" % (real_header, hosts_line) + prev_info = eh.get_entry(local_ip) + need_change = False + if not prev_info: + eh.add_entry(local_ip, fqdn, hostname) + need_change = True + else: + need_change = True + for entry in prev_info: + if sorted(entry) == sorted([fqdn, hostname]): + # Exists already, leave it be need_change = False - need_write = True - new_etchosts.write("%s\n" % (line)) + break + if need_change: + # Doesn't exist, change the first + # entry to be this entry + new_entries = list(prev_info) + new_entries[0] = [fqdn, hostname] + eh.del_entries(local_ip) + for entry in new_entries: + if len(entry) == 1: + eh.add_entry(local_ip, entry[0]) + elif len(entry) >= 2: + eh.add_entry(local_ip, *entry) if need_change: - new_etchosts.write("%s\n%s\n" % (real_header, hosts_line)) - need_write = True - if need_write: - contents = new_etchosts.getvalue() - util.write_file(self._paths.join(False, "/etc/hosts"), - contents, mode=0644) + contents = StringIO() + if header: + contents.write("%s\n" % (header)) + contents.write("%s\n" % (eh)) + util.write_file("/etc/hosts", contents.getvalue(), mode=0644) def _interface_action(self, action): if action not in IFACE_ACTIONS: diff --git a/cloudinit/distros/helpers.py b/cloudinit/distros/helpers.py index 251d5051..916935eb 100644 --- a/cloudinit/distros/helpers.py +++ b/cloudinit/distros/helpers.py @@ -23,6 +23,87 @@ from StringIO import StringIO from cloudinit import util +def _chop_comment(text, comment_chars): + comment_locations = [text.find(c) for c in comment_chars] + comment_locations = [c for c in comment_locations if c != -1] + if not comment_locations: + return (text, '') + min_comment = min(comment_locations) + before_comment = text[0:min_comment] + comment = text[min_comment:] + return (before_comment, comment) + + +# See: man hosts +# or http://unixhelp.ed.ac.uk/CGI/man-cgi?hosts +class HostsConf(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 get_entry(self, ip): + self.parse() + options = [] + for (line_type, components) in self._contents: + if line_type == 'option': + (pieces, _tail) = components + if len(pieces) and pieces[0] == ip: + options.append(pieces[1:]) + return options + + def del_entries(self, ip): + self.parse() + n_entries = [] + for (line_type, components) in self._contents: + if line_type != 'option': + n_entries.append((line_type, components)) + continue + else: + (pieces, _tail) = components + if len(pieces) and pieces[0] == ip: + pass + elif len(pieces): + n_entries.append((line_type, list(components))) + self._contents = n_entries + + def add_entry(self, ip, canonical_hostname, *aliases): + self.parse() + self._contents.append(('option', + ([ip, canonical_hostname] + list(aliases), ''))) + + def _parse(self, contents): + entries = [] + 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(('option', [head.split(None), tail])) + return entries + + def __str__(self): + self.parse() + contents = StringIO() + for (line_type, components) in self._contents: + if line_type == 'blank': + contents.write("%s\n") + elif line_type == 'all_comment': + contents.write("%s\n" % (components[0])) + elif line_type == 'option': + (pieces, tail) = components + pieces = [str(p) for p in pieces] + pieces = "\t".join(pieces) + contents.write("%s%s\n" % (pieces, tail)) + return contents.getvalue() + + # See: man resolv.conf class ResolvConf(object): def __init__(self, text): @@ -151,20 +232,7 @@ class ResolvConf(object): if not sline: entries.append(('blank', [line])) continue - comment_s_loc = sline.find(";") - comment_h_loc = sline.find("#") - comment_loc = -1 - if comment_s_loc != -1 and comment_h_loc != -1: - comment_loc = min(comment_h_loc, comment_s_loc) - elif comment_s_loc != -1: - comment_loc = comment_s_loc - elif comment_h_loc != -1: - comment_loc = comment_h_loc - head = line - tail = None - if comment_loc != -1: - head = line[:comment_loc] - tail = line[comment_loc:] + (head, tail) = _chop_comment(line, ';#') if not len(head.strip()): entries.append(('all_comment', [line])) continue |