add support for 'remotes'

2 files changed, 155 insertions, 3 deletions

diff --git a/cloudinit/config/cc_rsyslog.py b/cloudinit/config/cc_rsyslog.py
index 9599e925..8c02e826 100644
--- a/cloudinit/config/cc_rsyslog.py
+++ b/cloudinit/config/cc_rsyslog.py
@@ -37,10 +37,33 @@ Under 'rsyslog' you can define:
     For simply logging to an existing remote syslog server, via udp:
       configs: ["*.* @192.168.1.1"]
 
+  - remotes: [default={}]
+    This is a dictionary of name / value pairs.
+    In comparison to 'config's, it is more focused in that it only supports
+    remote syslog configuration.  It is not rsyslog specific, and could
+    convert to other syslog implementations.
+
+    Each entry in remotes is a 'name' and a 'value'.
+     * name: an string identifying the entry.  good practice would indicate
+       using a consistent and identifiable string for the producer.
+       For example, the MAAS service could use 'maas' as the key.
+     * value consists of the following parts:
+       * optional filter for log messages
+         default if not present: *.*
+       * optional leading '@' or '@@' (indicates udp or tcp respectively).
+         default if not present (udp): @
+         This is rsyslog format for that. if not present, is '@'.
+       * ipv4 or ipv6 or hostname
+         ipv6 addresses must be in [::1] format. (@[fd00::1]:514)
+       * optional port
+         port defaults to 514
+
   - config_filename: [default=20-cloud-config.conf]
     this is the file name to use if none is provided in a config entry.
+
   - config_dir: [default=/etc/rsyslog.d]
     this directory is used for filenames that are not absolute paths.
+
   - service_reload_command: [default="auto"]
     this command is executed if files have been written and thus the syslog
     daemon needs to be told.
@@ -61,9 +84,12 @@ Example config:
     configs:
       - "*.* @@192.158.1.1"
       - content: "*.*   @@192.0.2.1:10514"
-      - filename: 01-examplecom.conf
+        filename: 01-example.conf
       - content: |
         *.*   @@syslogd.example.com
+    remotes:
+      maas: "192.168.1.1"
+      juju: "10.0.4.1"
     config_dir: config_dir
     config_filename: config_filename
     service_reload_command: [your, syslog, restart, command]
@@ -77,6 +103,7 @@ Example Legacy config:
 """
 
 import os
+import re
 import six
 
 from cloudinit import log as logging
@@ -85,6 +112,7 @@ from cloudinit import util
 DEF_FILENAME = "20-cloud-config.conf"
 DEF_DIR = "/etc/rsyslog.d"
 DEF_RELOAD = "auto"
+DEF_REMOTES = {}
 
 KEYNAME_CONFIGS = 'configs'
 KEYNAME_FILENAME = 'config_filename'
@@ -92,9 +120,15 @@ KEYNAME_DIR = 'config_dir'
 KEYNAME_RELOAD = 'service_reload_command'
 KEYNAME_LEGACY_FILENAME = 'rsyslog_filename'
 KEYNAME_LEGACY_DIR = 'rsyslog_dir'
+KEYNAME_REMOTES = 'remotes'
 
 LOG = logging.getLogger(__name__)
 
+COMMENT_RE = re.compile(r'[ ]*[#]+[ ]*')
+HOST_PORT_RE = re.compile(
+    r'^(?P<proto>[@]{0,2})'
+    '(([[](?P<bracket_addr>[^\]]*)[\]])|(?P<addr>[^:]*))'
+    '([:](?P<port>[0-9]+))?$')
 
 def reload_syslog(command=DEF_RELOAD, systemd=False):
     service = 'rsyslog'
@@ -124,7 +158,8 @@ def load_config(cfg):
         (KEYNAME_CONFIGS, [], list),
         (KEYNAME_DIR, DEF_DIR, six.string_types),
         (KEYNAME_FILENAME, DEF_FILENAME, six.string_types),
-        (KEYNAME_RELOAD, DEF_RELOAD, six.string_types + (list,)))
+        (KEYNAME_RELOAD, DEF_RELOAD, six.string_types + (list,)),
+        (KEYNAME_REMOTES, DEF_REMOTES, dict))
 
     for key, default, vtypes in fillup:
         if key not in mycfg or not isinstance(mycfg[key], vtypes):
@@ -171,6 +206,113 @@ def apply_rsyslog_changes(configs, def_fname, cfg_dir):
     return files
 
 
+def parse_remotes_line(line, name=None):
+    try:
+        data, comment = COMMENT_RE.split(line)
+        comment = comment.strip()
+    except ValueError:
+        data, comment = (line, None)
+
+    toks = data.strip().split()
+    match = None
+    if len(toks) == 1:
+        host_port = data
+    elif len(toks) == 2:
+        match, host_port = toks
+    else:
+        raise ValueError("line had multiple spaces: %s" % data)
+
+    toks = HOST_PORT_RE.match(host_port)
+
+    if not toks:
+        raise ValueError("Invalid host specification '%s'" % host_port)
+
+    proto = toks.group('proto')
+    addr = toks.group('addr') or toks.group('bracket_addr')
+    port = toks.group('port')
+
+    if addr.startswith("[") and not addr.endswith("]"):
+        raise ValueError("host spec had invalid brackets: %s" % addr)
+
+    if comment and not name:
+        name = comment
+
+    t = SyslogRemotesLine(name=name, match=match, proto=proto,
+                          addr=addr, port=port)
+    t.validate()
+    return t
+
+
+class SyslogRemotesLine(object):
+    def __init__(self, name=None, match=None, proto=None, addr=None,
+                 port=None):
+        if not match:
+            match = "*.*"
+        self.name = name
+        self.match = match
+        if proto == "@":
+            proto = "udp"
+        elif proto == "@@":
+            proto = "tcp"
+        self.proto = proto
+
+        self.addr = addr
+        if port:
+            self.port = int(port)
+        else:
+            self.port = None
+
+    def validate(self):
+        if self.port:
+            try:
+                int(self.port)
+            except ValueError:
+                raise ValueError("port '%s' is not an integer" % self.port)
+
+        if not self.addr:
+            raise ValueError("address is required")
+
+    def __repr__(self):
+        return "[name=%s match=%s proto=%s address=%s port=%s]" % (
+            self.name, self.match, self.proto, self.addr, self.port
+        )
+
+    def __str__(self):
+        buf = self.match + " "
+        if self.proto == "udp":
+            buf += " @"
+        elif self.proto == "tcp":
+            buf += " @@"
+
+        if ":" in self.addr:
+            buf += "[" + self.addr + "]"
+        else:
+            buf += self.addr
+
+        if self.port:
+            buf += ":%s" % self.port
+
+        if self.name:
+            buf += " # %s" % self.name
+        return buf
+
+
+def remotes_to_rsyslog_cfg(remotes, header=None, footer=None):
+    if not remotes:
+        return None
+    lines = []
+    if header is not None:
+        lines.append(header)
+    for name, line in remotes.items():
+        try:
+            lines.append(parse_remotes_line(line, name=name))
+        except ValueError as e:
+            LOG.warn("failed loading remote %s: %s [%s]", name, line, e)
+    if footer is not None:
+        lines.append(footer)
+    return '\n'.join(str(lines)) + '\n'
+
+
 def handle(name, cfg, cloud, log, _args):
     if 'rsyslog' not in cfg:
         log.debug(("Skipping module named %s,"
@@ -178,6 +320,16 @@ def handle(name, cfg, cloud, log, _args):
         return
 
     mycfg = load_config(cfg)
+    configs = mycfg[KEYNAME_CONFIGS]
+
+    if mycfg[KEYNAME_REMOTES]:
+        configs.append(
+            remotes_to_rsyslog_cfg(
+                mycfg[KEYNAME_REMOTES],
+                header="# begin remotes",
+                footer="# end remotes",
+            ))
+
     if not mycfg['configs']:
         log.debug("Empty config rsyslog['configs'], nothing to do")
         return
diff --git a/cloudinit/config/cc_syslog.py b/cloudinit/config/cc_syslog.py
index 21a8e8a9..27793f8b 100644
--- a/cloudinit/config/cc_syslog.py
+++ b/cloudinit/config/cc_syslog.py
@@ -168,7 +168,7 @@ def handle(name, cfg, cloud, log, args):
         LOG.debug("syslog/remotes_file empty, doing nothing")
         return
 
-    remotes = mycfg.get('remotes_dict', {})
+    remotes = mycfg.get('remotes', {})
     if remotes and not isinstance(remotes, dict):
         LOG.warn("syslog/remotes: content is not a dictionary")
         return