ceph.in: rip out reusable code to pybind/ceph_argparse.py

Signed-off-by: Dan Mick <dan.mick@inktank.com>

Conflicts:
	src/ceph.in

4 files changed, 943 insertions, 928 deletions

diff --git a/ceph.spec.in b/ceph.spec.in
index b1f74b33722..3d90dd006b1 100644
--- a/ceph.spec.in
+++ b/ceph.spec.in
@@ -553,6 +553,7 @@ fi
 %{python_sitelib}/rados.py*
 %{python_sitelib}/rbd.py*
 %{python_sitelib}/cephfs.py*
+%{python_sitelib}/ceph_argparse.py*
 
 #################################################################################
 %files -n rest-bench
diff --git a/src/Makefile.am b/src/Makefile.am
index c792f104223..e751411f6a5 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -1575,7 +1575,8 @@ dist-hook:
 
 python_PYTHON = pybind/rados.py \
 		pybind/rbd.py \
-		pybind/cephfs.py
+		pybind/cephfs.py \
+		pybind/ceph_argparse.py
 
 # headers... and everything else we want to include in a 'make dist' 
 # that autotools doesn't magically identify.
diff --git a/src/ceph.in b/src/ceph.in
index 7303fb4014f..652abf0736d 100755
--- a/src/ceph.in
+++ b/src/ceph.in
@@ -33,788 +33,32 @@ if MYDIR.endswith('src') and \
     sys.path.insert(0, os.path.join(MYDIR, 'pybind'))
 
 import argparse
-import copy
 import errno
 import json
 import rados
 import signal
 import socket
-import stat
 import string
 import struct
 import subprocess
-import types
-import uuid
+
+from ceph_argparse import *
 
 # just a couple of globals
 
 verbose = False
 cluster_handle = None
 
-class ArgumentError(Exception):
-    """
-    Something wrong with arguments
-    """
-    pass
-
-class ArgumentNumber(ArgumentError):
-    """
-    Wrong number of a repeated argument
-    """
-    pass
-
-class ArgumentFormat(ArgumentError):
-    """
-    Argument value has wrong format
-    """
-    pass
-
-class ArgumentValid(ArgumentError):
-    """
-    Argument value is otherwise invalid (doesn't match choices, for instance)
-    """
-    pass
-
-class ArgumentPrefix(ArgumentError):
-    """
-    Special for mismatched prefix; less severe, don't report by default
-    """
-    pass
-
-class JsonFormat(Exception):
-    """
-    some syntactic or semantic issue with the JSON
-    """
-    pass
-
-class CephArgtype(object):
-    """
-    Base class for all Ceph argument types
-
-    Instantiating an object sets any validation parameters
-    (allowable strings, numeric ranges, etc.).  The 'valid'
-    method validates a string against that initialized instance,
-    throwing ArgumentError if there's a problem.
-    """
-    def __init__(self, **kwargs):
-        """
-        set any per-instance validation parameters here
-        from kwargs (fixed string sets, integer ranges, etc)
-        """
-        pass
-
-    def valid(self, s, partial=False):
-        """
-        Run validation against given string s (generally one word);
-        partial means to accept partial string matches (begins-with).
-        If cool, set self.val to the value that should be returned
-        (a copy of the input string, or a numeric or boolean interpretation
-        thereof, for example), and return True
-        if not, throw ArgumentError(msg-as-to-why)
-        """
-        self.val = s
-        return True
-
-    def __repr__(self):
-        """
-        return string representation of description of type.  Note,
-        this is not a representation of the actual value.  Subclasses
-        probably also override __str__() to give a more user-friendly
-        'name/type' description for use in command format help messages.
-        """
-        a = ''
-        if hasattr(self, 'typeargs'):
-            a = self.typeargs
-        return '{0}(\'{1}\')'.format(self.__class__.__name__, a)
-
-    def __str__(self):
-        """
-        where __repr__ (ideally) returns a string that could be used to
-        reproduce the object, __str__ returns one you'd like to see in
-        print messages.  Use __str__ to format the argtype descriptor
-        as it would be useful in a command usage message.
-        """
-        return '<{0}>'.format(self.__class__.__name__)
-
-class CephInt(CephArgtype):
-    """
-    range-limited integers, [+|-][0-9]+ or 0x[0-9a-f]+
-    range: list of 1 or 2 ints, [min] or [min,max]
-    """
-    def __init__(self, range=''):
-        if range == '':
-            self.range = list()
-        else:
-            self.range = list(range.split('|'))
-            self.range = map(long, self.range)
-
-    def valid(self, s, partial=False):
-        try:
-            val = long(s)
-        except ValueError:
-            raise ArgumentValid("{0} doesn't represent an int".format(s))
-        if len(self.range) == 2:
-            if val < self.range[0] or val > self.range[1]:
-                raise ArgumentValid("{0} not in range {1}".format(val, self.range))
-        elif len(self.range) == 1:
-            if val < self.range[0]:
-                raise ArgumentValid("{0} not in range {1}".format(val, self.range))
-        self.val = val
-        return True
-
-    def __str__(self):
-        r = ''
-        if len(self.range) == 1:
-            r = '[{0}-]'.format(self.range[0])
-        if len(self.range) == 2:
-            r = '[{0}-{1}]'.format(self.range[0], self.range[1])
-
-        return '<int{0}>'.format(r)
-
-
-class CephFloat(CephArgtype):
-    """
-    range-limited float type
-    range: list of 1 or 2 floats, [min] or [min, max]
-    """
-    def __init__(self, range=''):
-        if range == '':
-            self.range = list()
-        else:
-            self.range = list(range.split('|'))
-            self.range = map(float, self.range)
-
-    def valid(self, s, partial=False):
-        try:
-            val = float(s)
-        except ValueError:
-            raise ArgumentValid("{0} doesn't represent a float".format(s))
-        if len(self.range) == 2:
-            if val < self.range[0] or val > self.range[1]:
-                raise ArgumentValid("{0} not in range {1}".format(val, self.range))
-        elif len(self.range) == 1:
-            if val < self.range[0]:
-                raise ArgumentValid("{0} not in range {1}".format(val, self.range))
-        self.val = val
-        return True
-
-    def __str__(self):
-        r = ''
-        if len(self.range) == 1:
-            r = '[{0}-]'.format(self.range[0])
-        if len(self.range) == 2:
-            r = '[{0}-{1}]'.format(self.range[0], self.range[1])
-        return '<float{0}>'.format(r)
-
-class CephString(CephArgtype):
-    """
-    String; pretty generic.
-    """
-    def __init__(self, badchars=''):
-        self.badchars = badchars
-
-    def valid(self, s, partial=False):
-        for c in self.badchars:
-            if c in s:
-                raise ArgumentFormat("bad char {0} in {1}".format(c, s))
-        self.val = s
-        return True
-
-    def __str__(self):
-        b = ''
-        if len(self.badchars):
-            b = '(without chars in {0})'.format(self.badchars)
-        return '<string{0}>'.format(b)
-
-class CephSocketpath(CephArgtype):
-    """
-    Admin socket path; check that it's readable and S_ISSOCK
-    """
-    def valid(self, s, partial=False):
-        mode = os.stat(s).st_mode
-        if not stat.S_ISSOCK(mode):
-            raise ArgumentValid('socket path {0} is not a socket'.format(s))
-        self.val = s
-        return True
-    def __str__(self):
-        return '<admin-socket-path>'
-
-class CephIPAddr(CephArgtype):
-    """
-    IP address (v4 or v6) with optional port
-    """
-    def valid(self, s, partial=False):
-        # parse off port, use socket to validate addr
-        type = 6
-        if s.startswith('['):
-            type = 6
-        elif s.find('.') != -1:
-            type = 4
-        if type == 4:
-            port = s.find(':')
-            if (port != -1):
-                a = s[:port]
-                p = s[port+1:]
-                if int(p) > 65535:
-                    raise ArgumentValid('{0}: invalid IPv4 port'.format(p))
-            else:
-                a = s
-                p = None
-            try:
-                socket.inet_pton(socket.AF_INET, a)
-            except:
-                raise ArgumentValid('{0}: invalid IPv4 address'.format(a))
-        else:
-            # v6
-            if s.startswith('['):
-                end = s.find(']')
-                if end == -1:
-                    raise ArgumentFormat('{0} missing terminating ]'.format(s))
-                if s[end+1] == ':':
-                    try:
-                        p = int(s[end+2])
-                    except:
-                        raise ArgumentValid('{0}: bad port number'.format(s))
-                a = s[1:end]
-            else:
-                a = s
-                p = None
-            try:
-                socket.inet_pton(socket.AF_INET6, a)
-            except:
-                raise ArgumentValid('{0} not valid IPv6 address'.format(s))
-        if p is not None and long(p) > 65535:
-            raise ArgumentValid("{0} not a valid port number".format(p))
-        self.val = s
-        return True
-
-    def __str__(self):
-        return '<IPaddr[:port]>'
-
-class CephEntityAddr(CephIPAddr):
-    """
-    EntityAddress, that is, IP address/nonce
-    """
-    def valid(self, s, partial=False):
-        ip, nonce = s.split('/')
-        if not super(self.__class__, self).valid(ip):
-            raise ArgumentValid('CephEntityAddr {0}: ip address invalid'.format(s))
-        self.val = s
-        return True
-
-    def __str__(self):
-        return '<EntityAddr>'
-
-class CephPoolname(CephArgtype):
-    """
-    Pool name; very little utility
-    """
-    def __str__(self):
-        return '<poolname>'
-
-class CephObjectname(CephArgtype):
-    """
-    Object name.  Maybe should be combined with Pool name as they're always
-    present in pairs, and then could be checked for presence
-    """
-    def valid(self, s, partial=False):
-        self.val = s
-        return True
-
-    def __str__(self):
-        return '<objectname>'
-
-class CephPgid(CephArgtype):
-    """
-    pgid, in form N.xxx (N = pool number, xxx = hex pgnum)
-    """
-    def valid(self, s, partial=False):
-        if s.find('.') == -1:
-            raise ArgumentFormat('pgid has no .')
-        poolid, pgnum = s.split('.')
-        if poolid < 0:
-            raise ArgumentFormat('pool {0} < 0'.format(poolid))
-        try:
-            pgnum = int(pgnum, 16)
-        except:
-            raise ArgumentFormat('pgnum {0} not hex integer'.format(pgnum))
-        self.val = s
-        return True
-
-    def __str__(self):
-        return '<pgid>'
-
-class CephName(CephArgtype):
-    """
-    Name (type.id) where:
-    type is osd|mon|client|mds
-    id is a base10 int, if type == osd, or a string otherwise
-
-    Also accept '*'
-    """
-    def valid(self, s, partial=False):
-        if s == '*':
-            self.val = s
-            self.nametype = None
-            self.nameid = None
-            return True
-        if s.find('.') == -1:
-            raise ArgumentFormat('CephName: no . in {0}'.format(s))
-        else:
-            t, i = s.split('.')
-            if not t in ('osd', 'mon', 'client', 'mds'):
-                raise ArgumentValid('unknown type ' + self.t)
-            if t == 'osd':
-                if i != '*':
-                    try:
-                        i = int(i)
-                    except:
-                        raise ArgumentFormat('osd id ' + i + ' not integer')
-            self.nametype = t
-        self.val = s
-        self.nameid = i
-        return True
-
-    def __str__(self):
-        return '<name (type.id)>'
-
-class CephOsdName(CephArgtype):
-    """
-    Like CephName, but specific to osds: allow <id> alone
-
-    osd.<id>, or <id>, or *, where id is a base10 int
-    """
-    def valid(self, s, partial=False):
-        if s == '*':
-            self.val = s
-            self.nametype = None
-            self.nameid = None
-            return True
-        if s.find('.') != -1:
-            t, i = s.split('.')
-        else:
-            t = 'osd'
-            i = s
-        if t != 'osd':
-            raise ArgumentValid('unknown type ' + self.t)
-        try:
-            i = int(i)
-        except:
-            raise ArgumentFormat('osd id ' + i + ' not integer')
-        self.nametype = t
-        self.nameid = i
-        self.val = i
-        return True
-
-    def __str__(self):
-        return '<osdname (id|osd.id)>'
-
-class CephChoices(CephArgtype):
-    """
-    Set of string literals; init with valid choices
-    """
-    def __init__(self, strings='', **kwargs):
-        self.strings=strings.split('|')
-
-    def valid(self, s, partial=False):
-        if not partial:
-            if not s in self.strings:
-                # show as __str__ does: {s1|s2..}
-                raise ArgumentValid("{0} not in {1}".format(s, self))
-            self.val = s
-            return True
-
-        # partial
-        for t in self.strings:
-            if t.startswith(s):
-                self.val = s
-                return True
-        raise ArgumentValid("{0} not in {1}".  format(s, self))
-
-    def __str__(self):
-        if len(self.strings) == 1:
-            return '{0}'.format(self.strings[0])
-        else:
-            return '{0}'.format('|'.join(self.strings))
-
-class CephFilepath(CephArgtype):
-    """
-    Openable file
-    """
-    def valid(self, s, partial=False):
-        try:
-            f = open(s, 'a+')
-        except Exception as e:
-            raise ArgumentValid('can\'t open {0}: {1}'.format(s, e))
-        f.close()
-        self.val = s
-        return True
-
-    def __str__(self):
-        return '<outfilename>'
-
-class CephFragment(CephArgtype):
-    """
-    'Fragment' ??? XXX
-    """
-    def valid(self, s, partial=False):
-        if s.find('/') == -1:
-            raise ArgumentFormat('{0}: no /'.format(s))
-        val, bits = s.split('/')
-        # XXX is this right?
-        if not val.startswith('0x'):
-            raise ArgumentFormat("{0} not a hex integer".format(val))
-        try:
-            long(val)
-        except:
-            raise ArgumentFormat('can\'t convert {0} to integer'.format(val))
-        try:
-            long(bits)
-        except:
-            raise ArgumentFormat('can\'t convert {0} to integer'.format(bits))
-        self.val = s
-        return True
-
-    def __str__(self):
-        return "<CephFS fragment ID (0xvvv/bbb)>"
-
-
-class CephUUID(CephArgtype):
-    """
-    CephUUID: pretty self-explanatory
-    """
-    def valid(self, s, partial=False):
-        try:
-            uuid.UUID(s)
-        except Exception as e:
-            raise ArgumentFormat('invalid UUID {0}: {1}'.format(s, e))
-        self.val = s
-        return True
-
-    def __str__(self):
-        return '<uuid>'
-
-
-class CephPrefix(CephArgtype):
-    """
-    CephPrefix: magic type for "all the first n fixed strings"
-    """
-    def __init__(self, prefix=''):
-        self.prefix = prefix
-
-    def valid(self, s, partial=False):
-        if partial:
-            if self.prefix.startswith(s):
-                self.val = s
-                return True
-        else:
-            if (s == self.prefix):
-                self.val = s
-                return True
-        raise ArgumentPrefix("no match for {0}".format(s))
-
-    def __str__(self):
-        return self.prefix
-
 ############################################################################
 
-
-class argdesc(object):
-    """
-    argdesc(typename, name='name', n=numallowed|N,
-            req=False, helptext=helptext, **kwargs (type-specific))
-
-    validation rules:
-    typename: type(**kwargs) will be constructed
-    later, type.valid(w) will be called with a word in that position
-
-    name is used for parse errors and for constructing JSON output
-    n is a numeric literal or 'n|N', meaning "at least one, but maybe more"
-    req=False means the argument need not be present in the list
-    helptext is the associated help for the command
-    anything else are arguments to pass to the type constructor.
-
-    self.instance is an instance of type t constructed with typeargs.
-
-    valid() will later be called with input to validate against it,
-    and will store the validated value in self.instance.val for extraction.
-    """
-    def __init__(self, t, name=None, n=1, req=True, **kwargs):
-        if isinstance(t, types.StringTypes):
-            self.t = CephPrefix
-            self.typeargs = {'prefix':t}
-            self.req = True
-        else:
-            self.t = t
-            self.typeargs = kwargs
-            self.req = bool(req == True or req == 'True')
-
-        self.name = name
-        self.N = (n in ['n', 'N'])
-        if self.N:
-            self.n = 1
-        else:
-            self.n = int(n)
-        self.instance = self.t(**self.typeargs)
-
-    def __repr__(self):
-        r = 'argdesc(' + str(self.t) + ', '
-        internals = ['N', 'typeargs', 'instance', 't']
-        for (k,v) in self.__dict__.iteritems():
-            if k.startswith('__') or k in internals:
-                pass
-            else:
-                # undo mods above
-                if k == 'n' and self.N:
-                    v = 'N'
-                r += '{0}={1}, '.format(k,v)
-        for (k,v) in self.typeargs.iteritems():
-                r += '{0}={1}, '.format(k,v)
-        return r[:-2] + ')'
-
-    def __str__(self):
-        if ((self.t == CephChoices and len(self.instance.strings) == 1)
-            or (self.t == CephPrefix)):
-            s = '{0}'.format(str(self.instance))
-        else:
-            s = '{0}({1})'.format(self.name, str(self.instance))
-            if self.N:
-                s += ' [' + str(self.instance) + '...]'
-        if not self.req:
-            s = '{' + s + '}'
-        return s
-
-    def helpstr(self):
-        """
-        like str(), but omit parameter names (except for CephString,
-        which really needs them)
-        """
-        if self.t == CephString:
-            chunk = '<{0}>'.format(self.name)
-        else:
-            chunk = str(self.instance)
-        s = '{0}'.format(chunk)
-        if self.N:
-            s += ' [' + chunk + '...]'
-        if not self.req:
-            s = '{' + s + '}'
-        return s
-
-def concise_sig(sig):
-    """
-    Return string representation of sig useful for syntax reference in help
-    """
-    first = True
-    s = ''
-    for d in sig:
-        if first:
-            first = False
-        else:
-            s += ' '
-        s += d.helpstr()
-    return s
-
-def parse_funcsig(sig):
-    """
-    parse a single descriptor (array of strings or dicts) into a
-    dict of function descriptor/validators (objects of CephXXX type)
-    """
-    newsig = []
-    argnum = 0
-    for desc in sig:
-        argnum += 1
-        if isinstance(desc, types.StringTypes):
-            t = CephPrefix
-            desc = {'type':t, 'name':'prefix', 'prefix':desc}
-        else:
-            # not a simple string, must be dict
-            if not 'type' in desc:
-                s = 'JSON descriptor {0} has no type'.format(sig)
-                raise JsonFormat(s)
-            # look up type string in our globals() dict; if it's an
-            # object of type types.TypeType, it must be a
-            # locally-defined class. otherwise, we haven't a clue.
-            if desc['type'] in globals():
-                t = globals()[desc['type']]
-                if type(t) != types.TypeType:
-                    s = 'unknown type {0}'.format(desc['type'])
-                    raise JsonFormat(s)
-            else:
-                s = 'unknown type {0}'.format(desc['type'])
-                raise JsonFormat(s)
-
-        kwargs = dict()
-        for key, val in desc.items():
-            if key not in ['type', 'name', 'n', 'req']:
-                kwargs[key] = val
-        newsig.append(argdesc(t,
-                              name=desc.get('name', None),
-                              n=desc.get('n', 1),
-                              req=desc.get('req', True),
-                              **kwargs))
-    return newsig
-
-
-def parse_json_funcsigs(s):
-    """
-    parse_json_funcsigs(s)
-
-    A function signature is mostly an array of argdesc; it's represented
-    in JSON as
-    {
-      "cmd001": {"sig":[ "type": type, "name": name, "n": num, "req":true|false <other param>], "help":helptext}
-       .
-       .
-       .
-      ]
-
-    A set of sigs is in an dict mapped by a unique number:
-    {
-      "cmd1": {
-         "sig": ["type.. ], "help":{"text":helptext}
-      }
-      "cmd2"{
-         "sig": [.. ], "help":{"text":helptext}
-      }
-    }
-
-    Parse the string s and return an dict of dicts, keyed by opcode;
-    each dict contains 'sig' with the array of descriptors, and 'help'
-    with the helptext.
-    """
-    try:
-        overall = json.loads(s)
-    except Exception as e:
-        print >> sys.stderr, "Couldn't parse JSON {0}: {1}".format(s, e)
-        raise e
-    sigdict = {}
-    for cmdtag, cmd in overall.iteritems():
-        helptext = cmd.get('help', 'no help available')
-        try:
-            sig = cmd['sig']
-        except KeyError:
-            s = "JSON descriptor {0} has no 'sig'".format(cmdtag)
-            raise JsonFormat(s)
-        newsig = parse_funcsig(sig)
-        sigdict[cmdtag] = {'sig':newsig, 'helptext':helptext}
-    return sigdict
-
-def validate_one(word, desc, partial=False):
-    """
-    validate_one(word, desc, partial=False)
-
-    validate word against the constructed instance of the type
-    in desc.  May raise exception.  If it returns false (and doesn't
-    raise an exception), desc.instance.val will
-    contain the validated value (in the appropriate type).
-    """
-    if desc.instance.valid(word, partial):
-        desc.numseen += 1
-        if desc.N:
-            desc.n = desc.numseen + 1
-        return True
-    return False
-
-def matchnum(args, signature, partial=False):
-    """
-    matchnum(s, signature, partial=False)
-
-    Returns number of arguments matched in s against signature.
-    Can be used to determine most-likely command for full or partial
-    matches (partial applies to string matches).
-    """
-    words = args[:]
-    mysig = copy.deepcopy(signature)
-    matchcnt = 0
-    for desc in mysig:
-        setattr(desc, 'numseen', 0)
-        while desc.numseen < desc.n:
-            # if there are no more arguments, return
-            if not words:
-                return matchcnt;
-            word = words.pop(0)
-            try:
-                validate_one(word, desc, partial)
-            except:
-                if not desc.req:
-                    # this wasn't required, so word may match the next desc
-                    words.insert(0, word)
-                    break
-                else:
-                    # it was required, and didn't match, return
-                    return matchcnt
-        if desc.req:
-            matchcnt += 1
-    return matchcnt
-
-def validate(args, signature, partial=False):
-    """
-    validate(s, signature, partial=False)
-
-    Assumes s represents a possible command input following format of
-    signature.  Runs a validation; no exception means it's OK.  Return
-    a dict containing all arguments named by their descriptor name
-    (with duplicate args per name accumulated into a space-separated
-    value).
-
-    If partial is set, allow partial matching (with partial dict returned)
-    """
-    words = args[:]
-    mysig = copy.deepcopy(signature)
-    d = dict()
-    for desc in mysig:
-        setattr(desc, 'numseen', 0)
-        while desc.numseen < desc.n:
-            if words:
-                word = words.pop(0)
-            else:
-                if desc.req:
-                    if desc.N and desc.numseen < 1:
-                        # wanted N, didn't even get 1
-                        if partial:
-                            return d
-                        raise ArgumentNumber('saw {0} of {1}, expected at least 1'.format(desc.numseen, desc))
-                    elif not desc.N and desc.numseen < desc.n:
-                        # wanted n, got too few
-                        if partial:
-                            return d
-                        raise ArgumentNumber('saw {0} of {1}, expected {2}'.format(desc.numseen, desc, desc.n))
-                break
-            try:
-                validate_one(word, desc)
-            except Exception as e:
-                # not valid; if not required, just push back for the next one
-                if not desc.req:
-                    words.insert(0, word)
-                    break
-                else:
-                    # hm, but it was required, so quit
-                    if partial:
-                        return d
-                    raise e
-
-            if desc.N:
-                # value should be a list
-                if desc.name in d:
-                    d[desc.name] += [desc.instance.val]
-                else:
-                    d[desc.name] = [desc.instance.val]
-            elif (desc.t == CephPrefix) and (desc.name in d):
-                # value should be a space-joined concatenation
-                d[desc.name] += ' ' + desc.instance.val
-            else:
-                # if first CephPrefix or any other type, just set it
-                d[desc.name] = desc.instance.val
-    return d
-
 def osdids():
-    ret, outbuf, outs = json_command(prefix='osd ls')
+    ret, outbuf, outs = json_command(cluster_handle, prefix='osd ls')
     if ret:
         raise RuntimeError('Can\'t contact mon for osd list')
     return [i for i in outbuf.split('\n') if i != '']
 
 def monids():
-    ret, outbuf, outs = json_command(prefix='mon dump',
+    ret, outbuf, outs = json_command(cluster_handle, prefix='mon dump',
                                      argdict={'format':'json'})
     if ret:
         raise RuntimeError('Can\'t contact mon for mon list')
@@ -822,7 +66,7 @@ def monids():
     return [m['name'] for m in d['mons']]
 
 def mdsids():
-    ret, outbuf, outs = json_command(prefix='mds dump',
+    ret, outbuf, outs = json_command(cluster_handle, prefix='mds dump',
                                      argdict={'format':'json'})
     if ret:
         raise RuntimeError('Can\'t contact mon for mds list')
@@ -903,8 +147,8 @@ def do_help(parser, help_all = False):
         if help_all, print help for daemon commands as well 
     """
 
-    def help_for_target(target):
-        ret, outbuf, outs = json_command(target=target,
+    def help_for_target(target, partial=None):
+        ret, outbuf, outs = json_command(cluster_handle, target=target,
                                          prefix='get_command_descriptions', 
                                          timeout=10)
         if ret:
@@ -1035,163 +279,6 @@ def format_help(cmddict):
 
     return fullusage
 
-def validate_command(parsed_args, sigdict, args):
-    """
-    turn args into a valid dictionary ready to be sent off as JSON,
-    validated against sigdict.
-    parsed_args is the namespace back from argparse
-    """
-    found = []
-    valid_dict = {}
-    if args:
-        # look for best match, accumulate possibles in bestcmds
-        # (so we can maybe give a more-useful error message)
-        best_match_cnt = 0
-        bestcmds = []
-        for cmdtag, cmd in sigdict.iteritems():
-            sig = cmd['sig']
-            matched = matchnum(args, sig, partial=True)
-            if (matched > best_match_cnt):
-                if verbose:
-                    print >> sys.stderr, \
-                        "better match: {0} > {1}: {2}:{3} ".format(matched,
-                                      best_match_cnt, cmdtag, concise_sig(sig))
-                best_match_cnt = matched
-                bestcmds = [{cmdtag:cmd}]
-            elif matched == best_match_cnt:
-                if verbose:
-                    print >> sys.stderr, \
-                        "equal match: {0} > {1}: {2}:{3} ".format(matched,
-                                      best_match_cnt, cmdtag, concise_sig(sig))
-                bestcmds.append({cmdtag:cmd})
-
-        if verbose:
-            print >> sys.stderr, "bestcmds: ", bestcmds
-
-        # for everything in bestcmds, look for a true match
-        for cmdsig in bestcmds:
-            for cmd in cmdsig.itervalues():
-                sig = cmd['sig']
-                helptext = cmd['helptext']
-                try:
-                    valid_dict = validate(args, sig)
-                    found = sig
-                    break
-                except ArgumentPrefix:
-                    # this means a CephPrefix type didn't match; since
-                    # this is common, just eat it
-                    pass
-                except ArgumentError as e:
-                    # prefixes matched, but some other arg didn't;
-                    # this is interesting information
-                    print >> sys.stderr, '{0}: invalid command'.\
-                        format(' '.join(args))
-                    print >> sys.stderr, '{0}'.format(e)
-                    print >> sys.stderr, "did you mean {0}?\n\t{1}".\
-                        format(concise_sig(sig), helptext)
-                    pass
-
-        if not found:
-            print >> sys.stderr, 'no valid command found'
-            print >> sys.stderr, 'close matches:'
-            for cmdsig in bestcmds:
-                for (cmdtag, cmd) in cmdsig.iteritems():
-                    print >> sys.stderr, concise_sig(cmd['sig'])
-            return None
-
-        if parsed_args.output_format:
-            valid_dict['format'] = parsed_args.output_format
-
-        if parsed_args.threshold:
-            valid_dict['threshold'] = parsed_args.threshold
-
-        return valid_dict
-
-def send_command(target=('mon', ''), cmd=[], inbuf='', timeout=0):
-    """
-    Send a command to a daemon using librados's
-    mon_command, osd_command, or pg_command.  Any bulk input data
-    comes in inbuf.
-
-    Returns (ret, outbuf, outs); ret is the return code, outbuf is
-    the outbl "bulk useful output" buffer, and outs is any status
-    or error message (intended for stderr).
-
-    If target is osd.N, send command to that osd (except for pgid cmds)
-    """
-    try:
-        if target[0] == 'osd':
-            osdid = target[1]
-
-            if verbose:
-                print >> sys.stderr, 'submit {0} to osd.{1}'.\
-                    format(cmd, osdid)
-            ret, outbuf, outs = \
-                cluster_handle.osd_command(osdid, cmd, inbuf, timeout)
-
-        elif target[0] == 'pg':
-            # leave it in cmddict for the OSD to use too
-            pgid = target[1]
-            if verbose:
-                print >> sys.stderr, 'submit {0} for pgid {1}'.\
-                    format(cmd, pgid)
-            ret, outbuf, outs = \
-                cluster_handle.pg_command(pgid, cmd, inbuf, timeout)
-
-        elif target[0] == 'mon':
-            if verbose:
-                print >> sys.stderr, '{0} to {1}'.\
-                    format(cmd, target[0])
-            if target[1] == '':
-                ret, outbuf, outs = cluster_handle.mon_command(cmd, inbuf, timeout)
-            else:
-                ret, outbuf, outs = cluster_handle.mon_command(cmd, inbuf, timeout, target[1])
-
-    except Exception as e:
-        raise RuntimeError('"{0}": exception {1}'.format(cmd, e))
-
-    return ret, outbuf, outs
-
-def json_command(target=('mon', ''), prefix=None, argdict=None, inbuf='',
-                 timeout=0):
-    """
-    Format up a JSON command and send it with send_command() above.
-    Prefix may be supplied separately or in argdict.  Any bulk input
-    data comes in inbuf.
-
-    If target is osd.N, send command to that osd (except for pgid cmds)
-    """
-    cmddict = {}
-    if prefix:
-        cmddict.update({'prefix':prefix})
-    if argdict:
-        cmddict.update(argdict)
-
-    # grab prefix for error messages
-    prefix = cmddict['prefix']
-
-    try:
-        if target[0] == 'osd':
-            osdtarg = CephName()
-            osdtarget = '{0}.{1}'.format(*target)
-            # prefer target from cmddict if present and valid
-            if 'target' in cmddict:
-                osdtarget = cmddict.pop('target')
-            try:
-                osdtarg.valid(osdtarget)
-                target = ('osd', osdtarg.nameid)
-            except:
-                # use the target we were originally given
-                pass
-
-        ret, outbuf, outs = send_command(target, [json.dumps(cmddict)],
-                                         inbuf, timeout)
-
-    except Exception as e:
-        raise RuntimeError('"{0}": exception {1}'.format(prefix, e))
-
-    return ret, outbuf, outs
-
 def admin_socket(asok_path, cmd):
     sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
     try:
@@ -1248,7 +335,8 @@ def new_style_command(parsed_args, cmdargs, target, sigdict, inbuf, verbose):
     if not got_command:
         if cmdargs:
             # Validate input args against list of sigs
-            valid_dict = validate_command(parsed_args, sigdict, cmdargs)
+            valid_dict = validate_command(parsed_args, sigdict, cmdargs,
+                                          verbose)
             if valid_dict:
                 got_command = True
             else:
@@ -1267,7 +355,8 @@ def new_style_command(parsed_args, cmdargs, target, sigdict, inbuf, verbose):
                 if valid_dict:
                     if verbose:
                         print >> sys.stderr, "Submitting command ", valid_dict
-                    ret, outbuf, outs = json_command(target=target,
+                    ret, outbuf, outs = json_command(cluster_handle,
+                                                     target=target,
                                                      argdict=valid_dict)
                     if ret:
                         sys.stderr.write('Error {0}: {1}'.format(ret, outs))
@@ -1277,7 +366,8 @@ def new_style_command(parsed_args, cmdargs, target, sigdict, inbuf, verbose):
 
     if verbose:
         print >> sys.stderr, "Submitting command ", valid_dict
-    return json_command(target=target, argdict=valid_dict, inbuf=inbuf)
+    return json_command(cluster_handle, target=target, argdict=valid_dict,
+                        inbuf=inbuf)
 
 OSD_TELL_MATCH = { \
     'sig': ['tell', {'name':'target','type':'CephName'}], \
@@ -1493,10 +583,10 @@ def main():
             sys.stdout.flush()
 
         # first do a ceph status
-        ret, outbuf, outs = json_command(prefix='status')
+        ret, outbuf, outs = json_command(cluster_handle, prefix='status')
         if ret == -errno.EINVAL:
             # try old mon
-            ret, outbuf, outs = send_command(cmd=['status'])
+            ret, outbuf, outs = send_command(cluster_handle, cmd=['status'])
             # old mon returns status to outs...ick
             if ret == 0:
                 outbuf += outs
@@ -1570,7 +660,7 @@ def main():
             prefix='{0}.{1}: '.format(*target)
             suffix='\n'
 
-        ret, outbuf, outs = json_command(target=target,
+        ret, outbuf, outs = json_command(cluster_handle, target=target,
                                          prefix='get_command_descriptions')
         compat = False
         if ret == -errno.EINVAL:
@@ -1582,7 +672,8 @@ def main():
                 childargs.extend(['--format', parsed_args.output_format])
             if parsed_args.threshold:
                 childargs.extend(['--threshold', parsed_args.threshold])
-            ret, outbuf, outs = send_command(target, childargs, inbuf)
+            ret, outbuf, outs = send_command(cluster_handle, target, childargs,
+                                             inbuf)
         elif ret:
             if ret < 0:
                 outs = 'problem getting command descriptions from {0}.{1}'.format(*target)
diff --git a/src/pybind/ceph_argparse.py b/src/pybind/ceph_argparse.py
new file mode 100644
index 00000000000..020ad5b3a80
--- /dev/null
+++ b/src/pybind/ceph_argparse.py
@@ -0,0 +1,922 @@
+import copy
+import json
+import os
+import socket
+import stat
+import sys
+import types
+import uuid
+
+class ArgumentError(Exception):
+    """
+    Something wrong with arguments
+    """
+    pass
+
+class ArgumentNumber(ArgumentError):
+    """
+    Wrong number of a repeated argument
+    """
+    pass
+
+class ArgumentFormat(ArgumentError):
+    """
+    Argument value has wrong format
+    """
+    pass
+
+class ArgumentValid(ArgumentError):
+    """
+    Argument value is otherwise invalid (doesn't match choices, for instance)
+    """
+    pass
+
+class ArgumentPrefix(ArgumentError):
+    """
+    Special for mismatched prefix; less severe, don't report by default
+    """
+    pass
+
+class JsonFormat(Exception):
+    """
+    some syntactic or semantic issue with the JSON
+    """
+    pass
+
+class CephArgtype(object):
+    """
+    Base class for all Ceph argument types
+
+    Instantiating an object sets any validation parameters
+    (allowable strings, numeric ranges, etc.).  The 'valid'
+    method validates a string against that initialized instance,
+    throwing ArgumentError if there's a problem.
+    """
+    def __init__(self, **kwargs):
+        """
+        set any per-instance validation parameters here
+        from kwargs (fixed string sets, integer ranges, etc)
+        """
+        pass
+
+    def valid(self, s, partial=False):
+        """
+        Run validation against given string s (generally one word);
+        partial means to accept partial string matches (begins-with).
+        If cool, set self.val to the value that should be returned
+        (a copy of the input string, or a numeric or boolean interpretation
+        thereof, for example), and return True
+        if not, throw ArgumentError(msg-as-to-why)
+        """
+        self.val = s
+        return True
+
+    def __repr__(self):
+        """
+        return string representation of description of type.  Note,
+        this is not a representation of the actual value.  Subclasses
+        probably also override __str__() to give a more user-friendly
+        'name/type' description for use in command format help messages.
+        """
+        a = ''
+        if hasattr(self, 'typeargs'):
+            a = self.typeargs
+        return '{0}(\'{1}\')'.format(self.__class__.__name__, a)
+
+    def __str__(self):
+        """
+        where __repr__ (ideally) returns a string that could be used to
+        reproduce the object, __str__ returns one you'd like to see in
+        print messages.  Use __str__ to format the argtype descriptor
+        as it would be useful in a command usage message.
+        """
+        return '<{0}>'.format(self.__class__.__name__)
+
+class CephInt(CephArgtype):
+    """
+    range-limited integers, [+|-][0-9]+ or 0x[0-9a-f]+
+    range: list of 1 or 2 ints, [min] or [min,max]
+    """
+    def __init__(self, range=''):
+        if range == '':
+            self.range = list()
+        else:
+            self.range = list(range.split('|'))
+            self.range = map(long, self.range)
+
+    def valid(self, s, partial=False):
+        try:
+            val = long(s)
+        except ValueError:
+            raise ArgumentValid("{0} doesn't represent an int".format(s))
+        if len(self.range) == 2:
+            if val < self.range[0] or val > self.range[1]:
+                raise ArgumentValid("{0} not in range {1}".format(val, self.range))
+        elif len(self.range) == 1:
+            if val < self.range[0]:
+                raise ArgumentValid("{0} not in range {1}".format(val, self.range))
+        self.val = val
+        return True
+
+    def __str__(self):
+        r = ''
+        if len(self.range) == 1:
+            r = '[{0}-]'.format(self.range[0])
+        if len(self.range) == 2:
+            r = '[{0}-{1}]'.format(self.range[0], self.range[1])
+
+        return '<int{0}>'.format(r)
+
+
+class CephFloat(CephArgtype):
+    """
+    range-limited float type
+    range: list of 1 or 2 floats, [min] or [min, max]
+    """
+    def __init__(self, range=''):
+        if range == '':
+            self.range = list()
+        else:
+            self.range = list(range.split('|'))
+            self.range = map(float, self.range)
+
+    def valid(self, s, partial=False):
+        try:
+            val = float(s)
+        except ValueError:
+            raise ArgumentValid("{0} doesn't represent a float".format(s))
+        if len(self.range) == 2:
+            if val < self.range[0] or val > self.range[1]:
+                raise ArgumentValid("{0} not in range {1}".format(val, self.range))
+        elif len(self.range) == 1:
+            if val < self.range[0]:
+                raise ArgumentValid("{0} not in range {1}".format(val, self.range))
+        self.val = val
+        return True
+
+    def __str__(self):
+        r = ''
+        if len(self.range) == 1:
+            r = '[{0}-]'.format(self.range[0])
+        if len(self.range) == 2:
+            r = '[{0}-{1}]'.format(self.range[0], self.range[1])
+        return '<float{0}>'.format(r)
+
+class CephString(CephArgtype):
+    """
+    String; pretty generic.
+    """
+    def __init__(self, badchars=''):
+        self.badchars = badchars
+
+    def valid(self, s, partial=False):
+        for c in self.badchars:
+            if c in s:
+                raise ArgumentFormat("bad char {0} in {1}".format(c, s))
+        self.val = s
+        return True
+
+    def __str__(self):
+        b = ''
+        if len(self.badchars):
+            b = '(without chars in {0})'.format(self.badchars)
+        return '<string{0}>'.format(b)
+
+class CephSocketpath(CephArgtype):
+    """
+    Admin socket path; check that it's readable and S_ISSOCK
+    """
+    def valid(self, s, partial=False):
+        mode = os.stat(s).st_mode
+        if not stat.S_ISSOCK(mode):
+            raise ArgumentValid('socket path {0} is not a socket'.format(s))
+        self.val = s
+        return True
+    def __str__(self):
+        return '<admin-socket-path>'
+
+class CephIPAddr(CephArgtype):
+    """
+    IP address (v4 or v6) with optional port
+    """
+    def valid(self, s, partial=False):
+        # parse off port, use socket to validate addr
+        type = 6
+        if s.startswith('['):
+            type = 6
+        elif s.find('.') != -1:
+            type = 4
+        if type == 4:
+            port = s.find(':')
+            if (port != -1):
+                a = s[:port]
+                p = s[port+1:]
+                if int(p) > 65535:
+                    raise ArgumentValid('{0}: invalid IPv4 port'.format(p))
+            else:
+                a = s
+                p = None
+            try:
+                socket.inet_pton(socket.AF_INET, a)
+            except:
+                raise ArgumentValid('{0}: invalid IPv4 address'.format(a))
+        else:
+            # v6
+            if s.startswith('['):
+                end = s.find(']')
+                if end == -1:
+                    raise ArgumentFormat('{0} missing terminating ]'.format(s))
+                if s[end+1] == ':':
+                    try:
+                        p = int(s[end+2])
+                    except:
+                        raise ArgumentValid('{0}: bad port number'.format(s))
+                a = s[1:end]
+            else:
+                a = s
+                p = None
+            try:
+                socket.inet_pton(socket.AF_INET6, a)
+            except:
+                raise ArgumentValid('{0} not valid IPv6 address'.format(s))
+        if p is not None and long(p) > 65535:
+            raise ArgumentValid("{0} not a valid port number".format(p))
+        self.val = s
+        return True
+
+    def __str__(self):
+        return '<IPaddr[:port]>'
+
+class CephEntityAddr(CephIPAddr):
+    """
+    EntityAddress, that is, IP address/nonce
+    """
+    def valid(self, s, partial=False):
+        ip, nonce = s.split('/')
+        if not super(self.__class__, self).valid(ip):
+            raise ArgumentValid('CephEntityAddr {0}: ip address invalid'.format(s))
+        self.val = s
+        return True
+
+    def __str__(self):
+        return '<EntityAddr>'
+
+class CephPoolname(CephArgtype):
+    """
+    Pool name; very little utility
+    """
+    def __str__(self):
+        return '<poolname>'
+
+class CephObjectname(CephArgtype):
+    """
+    Object name.  Maybe should be combined with Pool name as they're always
+    present in pairs, and then could be checked for presence
+    """
+    def valid(self, s, partial=False):
+        self.val = s
+        return True
+
+    def __str__(self):
+        return '<objectname>'
+
+class CephPgid(CephArgtype):
+    """
+    pgid, in form N.xxx (N = pool number, xxx = hex pgnum)
+    """
+    def valid(self, s, partial=False):
+        if s.find('.') == -1:
+            raise ArgumentFormat('pgid has no .')
+        poolid, pgnum = s.split('.')
+        if poolid < 0:
+            raise ArgumentFormat('pool {0} < 0'.format(poolid))
+        try:
+            pgnum = int(pgnum, 16)
+        except:
+            raise ArgumentFormat('pgnum {0} not hex integer'.format(pgnum))
+        self.val = s
+        return True
+
+    def __str__(self):
+        return '<pgid>'
+
+class CephName(CephArgtype):
+    """
+    Name (type.id) where:
+    type is osd|mon|client|mds
+    id is a base10 int, if type == osd, or a string otherwise
+
+    Also accept '*'
+    """
+    def valid(self, s, partial=False):
+        if s == '*':
+            self.val = s
+            self.nametype = None
+            self.nameid = None
+            return True
+        if s.find('.') == -1:
+            raise ArgumentFormat('CephName: no . in {0}'.format(s))
+        else:
+            t, i = s.split('.')
+            if not t in ('osd', 'mon', 'client', 'mds'):
+                raise ArgumentValid('unknown type ' + self.t)
+            if t == 'osd':
+                if i != '*':
+                    try:
+                        i = int(i)
+                    except:
+                        raise ArgumentFormat('osd id ' + i + ' not integer')
+            self.nametype = t
+        self.val = s
+        self.nameid = i
+        return True
+
+    def __str__(self):
+        return '<name (type.id)>'
+
+class CephOsdName(CephArgtype):
+    """
+    Like CephName, but specific to osds: allow <id> alone
+
+    osd.<id>, or <id>, or *, where id is a base10 int
+    """
+    def valid(self, s, partial=False):
+        if s == '*':
+            self.val = s
+            self.nametype = None
+            self.nameid = None
+            return True
+        if s.find('.') != -1:
+            t, i = s.split('.')
+        else:
+            t = 'osd'
+            i = s
+        if t != 'osd':
+            raise ArgumentValid('unknown type ' + self.t)
+        try:
+            i = int(i)
+        except:
+            raise ArgumentFormat('osd id ' + i + ' not integer')
+        self.nametype = t
+        self.nameid = i
+        self.val = i
+        return True
+
+    def __str__(self):
+        return '<osdname (id|osd.id)>'
+
+class CephChoices(CephArgtype):
+    """
+    Set of string literals; init with valid choices
+    """
+    def __init__(self, strings='', **kwargs):
+        self.strings=strings.split('|')
+
+    def valid(self, s, partial=False):
+        if not partial:
+            if not s in self.strings:
+                # show as __str__ does: {s1|s2..}
+                raise ArgumentValid("{0} not in {1}".format(s, self))
+            self.val = s
+            return True
+
+        # partial
+        for t in self.strings:
+            if t.startswith(s):
+                self.val = s
+                return True
+        raise ArgumentValid("{0} not in {1}".  format(s, self))
+
+    def __str__(self):
+        if len(self.strings) == 1:
+            return '{0}'.format(self.strings[0])
+        else:
+            return '{0}'.format('|'.join(self.strings))
+
+class CephFilepath(CephArgtype):
+    """
+    Openable file
+    """
+    def valid(self, s, partial=False):
+        try:
+            f = open(s, 'a+')
+        except Exception as e:
+            raise ArgumentValid('can\'t open {0}: {1}'.format(s, e))
+        f.close()
+        self.val = s
+        return True
+
+    def __str__(self):
+        return '<outfilename>'
+
+class CephFragment(CephArgtype):
+    """
+    'Fragment' ??? XXX
+    """
+    def valid(self, s, partial=False):
+        if s.find('/') == -1:
+            raise ArgumentFormat('{0}: no /'.format(s))
+        val, bits = s.split('/')
+        # XXX is this right?
+        if not val.startswith('0x'):
+            raise ArgumentFormat("{0} not a hex integer".format(val))
+        try:
+            long(val)
+        except:
+            raise ArgumentFormat('can\'t convert {0} to integer'.format(val))
+        try:
+            long(bits)
+        except:
+            raise ArgumentFormat('can\'t convert {0} to integer'.format(bits))
+        self.val = s
+        return True
+
+    def __str__(self):
+        return "<CephFS fragment ID (0xvvv/bbb)>"
+
+
+class CephUUID(CephArgtype):
+    """
+    CephUUID: pretty self-explanatory
+    """
+    def valid(self, s, partial=False):
+        try:
+            uuid.UUID(s)
+        except Exception as e:
+            raise ArgumentFormat('invalid UUID {0}: {1}'.format(s, e))
+        self.val = s
+        return True
+
+    def __str__(self):
+        return '<uuid>'
+
+
+class CephPrefix(CephArgtype):
+    """
+    CephPrefix: magic type for "all the first n fixed strings"
+    """
+    def __init__(self, prefix=''):
+        self.prefix = prefix
+
+    def valid(self, s, partial=False):
+        if partial:
+            if self.prefix.startswith(s):
+                self.val = s
+                return True
+        else:
+            if (s == self.prefix):
+                self.val = s
+                return True
+        raise ArgumentPrefix("no match for {0}".format(s))
+
+    def __str__(self):
+        return self.prefix
+
+
+class argdesc(object):
+    """
+    argdesc(typename, name='name', n=numallowed|N,
+            req=False, helptext=helptext, **kwargs (type-specific))
+
+    validation rules:
+    typename: type(**kwargs) will be constructed
+    later, type.valid(w) will be called with a word in that position
+
+    name is used for parse errors and for constructing JSON output
+    n is a numeric literal or 'n|N', meaning "at least one, but maybe more"
+    req=False means the argument need not be present in the list
+    helptext is the associated help for the command
+    anything else are arguments to pass to the type constructor.
+
+    self.instance is an instance of type t constructed with typeargs.
+
+    valid() will later be called with input to validate against it,
+    and will store the validated value in self.instance.val for extraction.
+    """
+    def __init__(self, t, name=None, n=1, req=True, **kwargs):
+        if isinstance(t, types.StringTypes):
+            self.t = CephPrefix
+            self.typeargs = {'prefix':t}
+            self.req = True
+        else:
+            self.t = t
+            self.typeargs = kwargs
+            self.req = bool(req == True or req == 'True')
+
+        self.name = name
+        self.N = (n in ['n', 'N'])
+        if self.N:
+            self.n = 1
+        else:
+            self.n = int(n)
+        self.instance = self.t(**self.typeargs)
+
+    def __repr__(self):
+        r = 'argdesc(' + str(self.t) + ', '
+        internals = ['N', 'typeargs', 'instance', 't']
+        for (k,v) in self.__dict__.iteritems():
+            if k.startswith('__') or k in internals:
+                pass
+            else:
+                # undo mods above
+                if k == 'n' and self.N:
+                    v = 'N'
+                r += '{0}={1}, '.format(k,v)
+        for (k,v) in self.typeargs.iteritems():
+                r += '{0}={1}, '.format(k,v)
+        return r[:-2] + ')'
+
+    def __str__(self):
+        if ((self.t == CephChoices and len(self.instance.strings) == 1)
+            or (self.t == CephPrefix)):
+            s = '{0}'.format(str(self.instance))
+        else:
+            s = '{0}({1})'.format(self.name, str(self.instance))
+            if self.N:
+                s += ' [' + str(self.instance) + '...]'
+        if not self.req:
+            s = '{' + s + '}'
+        return s
+
+    def helpstr(self):
+        """
+        like str(), but omit parameter names (except for CephString,
+        which really needs them)
+        """
+        if self.t == CephString:
+            chunk = '<{0}>'.format(self.name)
+        else:
+            chunk = str(self.instance)
+        s = '{0}'.format(chunk)
+        if self.N:
+            s += ' [' + chunk + '...]'
+        if not self.req:
+            s = '{' + s + '}'
+        return s
+
+def concise_sig(sig):
+    """
+    Return string representation of sig useful for syntax reference in help
+    """
+    first = True
+    s = ''
+    for d in sig:
+        if first:
+            first = False
+        else:
+            s += ' '
+        s += d.helpstr()
+    return s
+
+def parse_funcsig(sig):
+    """
+    parse a single descriptor (array of strings or dicts) into a
+    dict of function descriptor/validators (objects of CephXXX type)
+    """
+    newsig = []
+    argnum = 0
+    for desc in sig:
+        argnum += 1
+        if isinstance(desc, types.StringTypes):
+            t = CephPrefix
+            desc = {'type':t, 'name':'prefix', 'prefix':desc}
+        else:
+            # not a simple string, must be dict
+            if not 'type' in desc:
+                s = 'JSON descriptor {0} has no type'.format(sig)
+                raise JsonFormat(s)
+            # look up type string in our globals() dict; if it's an
+            # object of type types.TypeType, it must be a
+            # locally-defined class. otherwise, we haven't a clue.
+            if desc['type'] in globals():
+                t = globals()[desc['type']]
+                if type(t) != types.TypeType:
+                    s = 'unknown type {0}'.format(desc['type'])
+                    raise JsonFormat(s)
+            else:
+                s = 'unknown type {0}'.format(desc['type'])
+                raise JsonFormat(s)
+
+        kwargs = dict()
+        for key, val in desc.items():
+            if key not in ['type', 'name', 'n', 'req']:
+                kwargs[key] = val
+        newsig.append(argdesc(t,
+                              name=desc.get('name', None),
+                              n=desc.get('n', 1),
+                              req=desc.get('req', True),
+                              **kwargs))
+    return newsig
+
+
+def parse_json_funcsigs(s):
+    """
+    parse_json_funcsigs(s)
+
+    A function signature is mostly an array of argdesc; it's represented
+    in JSON as
+    {
+      "cmd001": {"sig":[ "type": type, "name": name, "n": num, "req":true|false <other param>], "help":helptext}
+       .
+       .
+       .
+      ]
+
+    A set of sigs is in an dict mapped by a unique number:
+    {
+      "cmd1": {
+         "sig": ["type.. ], "help":{"text":helptext}
+      }
+      "cmd2"{
+         "sig": [.. ], "help":{"text":helptext}
+      }
+    }
+
+    Parse the string s and return an dict of dicts, keyed by opcode;
+    each dict contains 'sig' with the array of descriptors, and 'help'
+    with the helptext.
+    """
+    try:
+        overall = json.loads(s)
+    except Exception as e:
+        print >> sys.stderr, "Couldn't parse JSON {0}: {1}".format(s, e)
+        raise e
+    sigdict = {}
+    for cmdtag, cmd in overall.iteritems():
+        helptext = cmd.get('help', 'no help available')
+        try:
+            sig = cmd['sig']
+        except KeyError:
+            s = "JSON descriptor {0} has no 'sig'".format(cmdtag)
+            raise JsonFormat(s)
+        newsig = parse_funcsig(sig)
+        sigdict[cmdtag] = {'sig':newsig, 'helptext':helptext}
+    return sigdict
+
+def validate_one(word, desc, partial=False):
+    """
+    validate_one(word, desc, partial=False)
+
+    validate word against the constructed instance of the type
+    in desc.  May raise exception.  If it returns false (and doesn't
+    raise an exception), desc.instance.val will
+    contain the validated value (in the appropriate type).
+    """
+    if desc.instance.valid(word, partial):
+        desc.numseen += 1
+        if desc.N:
+            desc.n = desc.numseen + 1
+        return True
+    return False
+
+def matchnum(args, signature, partial=False):
+    """
+    matchnum(s, signature, partial=False)
+
+    Returns number of arguments matched in s against signature.
+    Can be used to determine most-likely command for full or partial
+    matches (partial applies to string matches).
+    """
+    words = args[:]
+    mysig = copy.deepcopy(signature)
+    matchcnt = 0
+    for desc in mysig:
+        setattr(desc, 'numseen', 0)
+        while desc.numseen < desc.n:
+            # if there are no more arguments, return
+            if not words:
+                return matchcnt;
+            word = words.pop(0)
+            try:
+                validate_one(word, desc, partial)
+            except:
+                if not desc.req:
+                    # this wasn't required, so word may match the next desc
+                    words.insert(0, word)
+                    break
+                else:
+                    # it was required, and didn't match, return
+                    return matchcnt
+        if desc.req:
+            matchcnt += 1
+    return matchcnt
+
+def validate(args, signature, partial=False):
+    """
+    validate(s, signature, partial=False)
+
+    Assumes s represents a possible command input following format of
+    signature.  Runs a validation; no exception means it's OK.  Return
+    a dict containing all arguments named by their descriptor name
+    (with duplicate args per name accumulated into a space-separated
+    value).
+
+    If partial is set, allow partial matching (with partial dict returned)
+    """
+    words = args[:]
+    mysig = copy.deepcopy(signature)
+    d = dict()
+    for desc in mysig:
+        setattr(desc, 'numseen', 0)
+        while desc.numseen < desc.n:
+            if words:
+                word = words.pop(0)
+            else:
+                if desc.req:
+                    if desc.N and desc.numseen < 1:
+                        # wanted N, didn't even get 1
+                        if partial:
+                            return d
+                        raise ArgumentNumber('saw {0} of {1}, expected at least 1'.format(desc.numseen, desc))
+                    elif not desc.N and desc.numseen < desc.n:
+                        # wanted n, got too few
+                        if partial:
+                            return d
+                        raise ArgumentNumber('saw {0} of {1}, expected {2}'.format(desc.numseen, desc, desc.n))
+                break
+            try:
+                validate_one(word, desc)
+            except Exception as e:
+                # not valid; if not required, just push back for the next one
+                if not desc.req:
+                    words.insert(0, word)
+                    break
+                else:
+                    # hm, but it was required, so quit
+                    if partial:
+                        return d
+                    raise e
+
+            if desc.N:
+                # value should be a list
+                if desc.name in d:
+                    d[desc.name] += [desc.instance.val]
+                else:
+                    d[desc.name] = [desc.instance.val]
+            elif (desc.t == CephPrefix) and (desc.name in d):
+                # value should be a space-joined concatenation
+                d[desc.name] += ' ' + desc.instance.val
+            else:
+                # if first CephPrefix or any other type, just set it
+                d[desc.name] = desc.instance.val
+    return d
+
+def validate_command(parsed_args, sigdict, args, verbose=False):
+    """
+    turn args into a valid dictionary ready to be sent off as JSON,
+    validated against sigdict.
+    parsed_args is the namespace back from argparse
+    """
+    found = []
+    valid_dict = {}
+    if args:
+        # look for best match, accumulate possibles in bestcmds
+        # (so we can maybe give a more-useful error message)
+        best_match_cnt = 0
+        bestcmds = []
+        for cmdtag, cmd in sigdict.iteritems():
+            sig = cmd['sig']
+            matched = matchnum(args, sig, partial=True)
+            if (matched > best_match_cnt):
+                if verbose:
+                    print >> sys.stderr, \
+                        "better match: {0} > {1}: {2}:{3} ".format(matched,
+                                      best_match_cnt, cmdtag, concise_sig(sig))
+                best_match_cnt = matched
+                bestcmds = [{cmdtag:cmd}]
+            elif matched == best_match_cnt:
+                if verbose:
+                    print >> sys.stderr, \
+                        "equal match: {0} > {1}: {2}:{3} ".format(matched,
+                                      best_match_cnt, cmdtag, concise_sig(sig))
+                bestcmds.append({cmdtag:cmd})
+
+        if verbose:
+            print >> sys.stderr, "bestcmds: ", bestcmds
+
+        # for everything in bestcmds, look for a true match
+        for cmdsig in bestcmds:
+            for cmd in cmdsig.itervalues():
+                sig = cmd['sig']
+                helptext = cmd['helptext']
+                try:
+                    valid_dict = validate(args, sig, verbose)
+                    found = sig
+                    break
+                except ArgumentPrefix:
+                    # this means a CephPrefix type didn't match; since
+                    # this is common, just eat it
+                    pass
+                except ArgumentError as e:
+                    # prefixes matched, but some other arg didn't;
+                    # this is interesting information if verbose
+                    if verbose:
+                        print >> sys.stderr, '{0}: invalid command'.\
+                            format(' '.join(args))
+                        print >> sys.stderr, '{0}'.format(e)
+                        print >> sys.stderr, "did you mean {0}?\n\t{1}".\
+                            format(concise_sig(sig), helptext)
+                    pass
+
+        if not found:
+            print >> sys.stderr, 'no valid command found; 10 closest matches:'
+            for cmdsig in bestcmds[:10]:
+                for (cmdtag, cmd) in cmdsig.iteritems():
+                    print >> sys.stderr, concise_sig(cmd['sig'])
+            return None
+
+        if parsed_args.output_format:
+            valid_dict['format'] = parsed_args.output_format
+
+        if parsed_args.threshold:
+            valid_dict['threshold'] = parsed_args.threshold
+
+        return valid_dict
+
+def send_command(cluster, target=('mon', ''), cmd=[], inbuf='', timeout=0, 
+                 verbose=False):
+    """
+    Send a command to a daemon using librados's
+    mon_command, osd_command, or pg_command.  Any bulk input data
+    comes in inbuf.
+
+    Returns (ret, outbuf, outs); ret is the return code, outbuf is
+    the outbl "bulk useful output" buffer, and outs is any status
+    or error message (intended for stderr).
+
+    If target is osd.N, send command to that osd (except for pgid cmds)
+    """
+    try:
+        if target[0] == 'osd':
+            osdid = target[1]
+
+            if verbose:
+                print >> sys.stderr, 'submit {0} to osd.{1}'.\
+                    format(cmd, osdid)
+            ret, outbuf, outs = \
+                cluster.osd_command(osdid, cmd, inbuf, timeout)
+
+        elif target[0] == 'pg':
+            # leave it in cmddict for the OSD to use too
+            pgid = target[1]
+            if verbose:
+                print >> sys.stderr, 'submit {0} for pgid {1}'.\
+                    format(cmd, pgid)
+            ret, outbuf, outs = \
+                cluster.pg_command(pgid, cmd, inbuf, timeout)
+
+        elif target[0] == 'mon':
+            if verbose:
+                print >> sys.stderr, '{0} to {1}'.\
+                    format(cmd, target[0])
+            if target[1] == '':
+                ret, outbuf, outs = cluster.mon_command(cmd, inbuf, timeout)
+            else:
+                ret, outbuf, outs = cluster.mon_command(cmd, inbuf, timeout, target[1])
+
+    except Exception as e:
+        raise RuntimeError('"{0}": exception {1}'.format(cmd, e))
+
+    return ret, outbuf, outs
+
+def json_command(cluster, target=('mon', ''), prefix=None, argdict=None,
+                 inbuf='', timeout=0, verbose=False):
+    """
+    Format up a JSON command and send it with send_command() above.
+    Prefix may be supplied separately or in argdict.  Any bulk input
+    data comes in inbuf.
+
+    If target is osd.N, send command to that osd (except for pgid cmds)
+    """
+    cmddict = {}
+    if prefix:
+        cmddict.update({'prefix':prefix})
+    if argdict:
+        cmddict.update(argdict)
+
+    # grab prefix for error messages
+    prefix = cmddict['prefix']
+
+    try:
+        if target[0] == 'osd':
+            osdtarg = CephName()
+            osdtarget = '{0}.{1}'.format(*target)
+            # prefer target from cmddict if present and valid
+            if 'target' in cmddict:
+                osdtarget = cmddict.pop('target')
+            try:
+                osdtarg.valid(osdtarget)
+                target = ('osd', osdtarg.nameid)
+            except:
+                # use the target we were originally given
+                pass
+
+        ret, outbuf, outs = send_command(cluster, target, [json.dumps(cmddict)],
+                                         inbuf, timeout, verbose)
+
+    except Exception as e:
+        raise RuntimeError('"{0}": exception {1}'.format(prefix, e))
+
+    return ret, outbuf, outs
+
+