4 # Copyright (C) 2006, 2007 Google Inc.
6 # This program is free software; you can redistribute it and/or modify
7 # it under the terms of the GNU General Public License as published by
8 # the Free Software Foundation; either version 2 of the License, or
9 # (at your option) any later version.
11 # This program is distributed in the hope that it will be useful, but
12 # WITHOUT ANY WARRANTY; without even the implied warranty of
13 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 # General Public License for more details.
16 # You should have received a copy of the GNU General Public License
17 # along with this program; if not, write to the Free Software
18 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
22 """Module dealing with command line parsing"""
29 from cStringIO import StringIO
31 from ganeti import utils
32 from ganeti import logger
33 from ganeti import errors
34 from ganeti import mcpu
35 from ganeti import constants
36 from ganeti import opcodes
38 from optparse import (OptionParser, make_option, TitledHelpFormatter,
39 Option, OptionValueError, SUPPRESS_HELP)
41 __all__ = ["DEBUG_OPT", "NOHDR_OPT", "SEP_OPT", "GenericMain", "SubmitOpCode",
42 "cli_option", "GenerateTable", "AskUser",
43 "ARGS_NONE", "ARGS_FIXED", "ARGS_ATLEAST", "ARGS_ANY", "ARGS_ONE",
44 "USEUNITS_OPT", "FIELDS_OPT", "FORCE_OPT",
45 "ListTags", "AddTags", "RemoveTags", "TAG_SRC_OPT",
46 "FormatError", "SplitNodeOption"
50 def _ExtractTagsObject(opts, args):
51 """Extract the tag type object.
53 Note that this function will modify its args parameter.
56 if not hasattr(opts, "tag_type"):
57 raise errors.ProgrammerError("tag_type not passed to _ExtractTagsObject")
59 if kind == constants.TAG_CLUSTER:
61 elif kind == constants.TAG_NODE or kind == constants.TAG_INSTANCE:
63 raise errors.OpPrereqError("no arguments passed to the command")
67 raise errors.ProgrammerError("Unhandled tag type '%s'" % kind)
71 def _ExtendTags(opts, args):
72 """Extend the args if a source file has been given.
74 This function will extend the tags with the contents of the file
75 passed in the 'tags_source' attribute of the opts parameter. A file
76 named '-' will be replaced by stdin.
79 fname = opts.tags_source
85 new_fh = open(fname, "r")
88 # we don't use the nice 'new_data = [line.strip() for line in fh]'
89 # because of python bug 1633941
91 line = new_fh.readline()
94 new_data.append(line.strip())
100 def ListTags(opts, args):
101 """List the tags on a given object.
103 This is a generic implementation that knows how to deal with all
104 three cases of tag objects (cluster, node, instance). The opts
105 argument is expected to contain a tag_type field denoting what
106 object type we work on.
109 kind, name = _ExtractTagsObject(opts, args)
110 op = opcodes.OpGetTags(kind=kind, name=name)
111 result = SubmitOpCode(op)
112 result = list(result)
118 def AddTags(opts, args):
119 """Add tags on a given object.
121 This is a generic implementation that knows how to deal with all
122 three cases of tag objects (cluster, node, instance). The opts
123 argument is expected to contain a tag_type field denoting what
124 object type we work on.
127 kind, name = _ExtractTagsObject(opts, args)
128 _ExtendTags(opts, args)
130 raise errors.OpPrereqError("No tags to be added")
131 op = opcodes.OpAddTags(kind=kind, name=name, tags=args)
135 def RemoveTags(opts, args):
136 """Remove tags from a given object.
138 This is a generic implementation that knows how to deal with all
139 three cases of tag objects (cluster, node, instance). The opts
140 argument is expected to contain a tag_type field denoting what
141 object type we work on.
144 kind, name = _ExtractTagsObject(opts, args)
145 _ExtendTags(opts, args)
147 raise errors.OpPrereqError("No tags to be removed")
148 op = opcodes.OpDelTags(kind=kind, name=name, tags=args)
152 DEBUG_OPT = make_option("-d", "--debug", default=False,
154 help="Turn debugging on")
156 NOHDR_OPT = make_option("--no-headers", default=False,
157 action="store_true", dest="no_headers",
158 help="Don't display column headers")
160 SEP_OPT = make_option("--separator", default=None,
161 action="store", dest="separator",
162 help="Separator between output fields"
163 " (defaults to one space)")
165 USEUNITS_OPT = make_option("--human-readable", default=False,
166 action="store_true", dest="human_readable",
167 help="Print sizes in human readable format")
169 FIELDS_OPT = make_option("-o", "--output", dest="output", action="store",
170 type="string", help="Select output fields",
173 FORCE_OPT = make_option("-f", "--force", dest="force", action="store_true",
174 default=False, help="Force the operation")
176 _LOCK_OPT = make_option("--lock-retries", default=None,
177 type="int", help=SUPPRESS_HELP)
179 TAG_SRC_OPT = make_option("--from", dest="tags_source",
180 default=None, help="File with tag names")
184 """Macro-like function denoting a fixed number of arguments"""
188 def ARGS_ATLEAST(val):
189 """Macro-like function denoting a minimum number of arguments"""
194 ARGS_ONE = ARGS_FIXED(1)
195 ARGS_ANY = ARGS_ATLEAST(0)
198 def check_unit(option, opt, value):
199 """OptParsers custom converter for units.
203 return utils.ParseUnit(value)
204 except errors.UnitParseError, err:
205 raise OptionValueError("option %s: %s" % (opt, err))
208 class CliOption(Option):
209 """Custom option class for optparse.
212 TYPES = Option.TYPES + ("unit",)
213 TYPE_CHECKER = copy.copy(Option.TYPE_CHECKER)
214 TYPE_CHECKER["unit"] = check_unit
217 # optparse.py sets make_option, so we do it for our own option class, too
218 cli_option = CliOption
221 def _ParseArgs(argv, commands):
222 """Parses the command line and return the function which must be
223 executed together with its arguments
226 argv: the command line
228 commands: dictionary with special contents, see the design doc for
235 binary = argv[0].split("/")[-1]
237 if len(argv) > 1 and argv[1] == "--version":
238 print "%s (ganeti) %s" % (binary, constants.RELEASE_VERSION)
239 # Quit right away. That way we don't have to care about this special
240 # argument. optparse.py does it the same.
243 if len(argv) < 2 or argv[1] not in commands.keys():
244 # let's do a nice thing
245 sortedcmds = commands.keys()
247 print ("Usage: %(bin)s {command} [options...] [argument...]"
248 "\n%(bin)s <command> --help to see details, or"
249 " man %(bin)s\n" % {"bin": binary})
250 # compute the max line length for cmd + usage
251 mlen = max([len(" %s %s" % (cmd, commands[cmd][3])) for cmd in commands])
252 mlen = min(60, mlen) # should not get here...
253 # and format a nice command list
255 for cmd in sortedcmds:
256 cmdstr = " %s %s" % (cmd, commands[cmd][3])
257 help_text = commands[cmd][4]
258 help_lines = textwrap.wrap(help_text, 79-3-mlen)
259 print "%-*s - %s" % (mlen, cmdstr,
261 for line in help_lines:
262 print "%-*s %s" % (mlen, "", line)
264 return None, None, None
266 func, nargs, parser_opts, usage, description = commands[cmd]
267 parser_opts.append(_LOCK_OPT)
268 parser = OptionParser(option_list=parser_opts,
269 description=description,
270 formatter=TitledHelpFormatter(),
271 usage="%%prog %s %s" % (cmd, usage))
272 parser.disable_interspersed_args()
273 options, args = parser.parse_args()
276 print >> sys.stderr, ("Error: Command %s expects no arguments" % cmd)
277 return None, None, None
278 elif nargs < 0 and len(args) != -nargs:
279 print >> sys.stderr, ("Error: Command %s expects %d argument(s)" %
281 return None, None, None
282 elif nargs >= 0 and len(args) < nargs:
283 print >> sys.stderr, ("Error: Command %s expects at least %d argument(s)" %
285 return None, None, None
287 return func, options, args
290 def SplitNodeOption(value):
291 """Splits the value of a --node option.
294 if value and ':' in value:
295 return value.split(':', 1)
300 def AskUser(text, choices=None):
301 """Ask the user a question.
304 text - the question to ask.
306 choices - list with elements tuples (input_char, return_value,
307 description); if not given, it will default to: [('y', True,
308 'Perform the operation'), ('n', False, 'Do no do the operation')];
309 note that the '?' char is reserved for help
311 Returns: one of the return values from the choices list; if input is
312 not possible (i.e. not running with a tty, we return the last entry
317 choices = [('y', True, 'Perform the operation'),
318 ('n', False, 'Do not perform the operation')]
319 if not choices or not isinstance(choices, list):
320 raise errors.ProgrammerError("Invalid choiches argument to AskUser")
321 for entry in choices:
322 if not isinstance(entry, tuple) or len(entry) < 3 or entry[0] == '?':
323 raise errors.ProgrammerError("Invalid choiches element to AskUser")
325 answer = choices[-1][1]
327 for line in text.splitlines():
328 new_text.append(textwrap.fill(line, 70, replace_whitespace=False))
329 text = "\n".join(new_text)
331 f = file("/dev/tty", "a+")
335 chars = [entry[0] for entry in choices]
336 chars[-1] = "[%s]" % chars[-1]
338 maps = dict([(entry[0], entry[1]) for entry in choices])
342 f.write("/".join(chars))
344 line = f.readline(2).strip().lower()
349 for entry in choices:
350 f.write(" %s - %s\n" % (entry[0], entry[2]))
358 def SubmitOpCode(op, proc=None, feedback_fn=None):
359 """Function to submit an opcode.
361 This is just a simple wrapper over the construction of the processor
362 instance. It should be extended to better handle feedback and
363 interaction functions.
366 if feedback_fn is None:
367 feedback_fn = logger.ToStdout
369 proc = mcpu.Processor(feedback=feedback_fn)
370 return proc.ExecOpCode(op)
373 def FormatError(err):
374 """Return a formatted error message for a given error.
376 This function takes an exception instance and returns a tuple
377 consisting of two values: first, the recommended exit code, and
378 second, a string describing the error message (not
385 if isinstance(err, errors.ConfigurationError):
386 txt = "Corrupt configuration file: %s" % msg
388 obuf.write(txt + "\n")
389 obuf.write("Aborting.")
391 elif isinstance(err, errors.HooksAbort):
392 obuf.write("Failure: hooks execution failed:\n")
393 for node, script, out in err.args[0]:
395 obuf.write(" node: %s, script: %s, output: %s\n" %
398 obuf.write(" node: %s, script: %s (no output)\n" %
400 elif isinstance(err, errors.HooksFailure):
401 obuf.write("Failure: hooks general failure: %s" % msg)
402 elif isinstance(err, errors.ResolverError):
403 this_host = utils.HostInfo.SysName()
404 if err.args[0] == this_host:
405 msg = "Failure: can't resolve my own hostname ('%s')"
407 msg = "Failure: can't resolve hostname '%s'"
408 obuf.write(msg % err.args[0])
409 elif isinstance(err, errors.OpPrereqError):
410 obuf.write("Failure: prerequisites not met for this"
411 " operation:\n%s" % msg)
412 elif isinstance(err, errors.OpExecError):
413 obuf.write("Failure: command execution error:\n%s" % msg)
414 elif isinstance(err, errors.TagError):
415 obuf.write("Failure: invalid tag(s) given:\n%s" % msg)
416 elif isinstance(err, errors.GenericError):
417 obuf.write("Unhandled Ganeti error: %s" % msg)
419 obuf.write("Unhandled exception: %s" % msg)
420 return retcode, obuf.getvalue().rstrip('\n')
423 def GenericMain(commands, override=None):
424 """Generic main function for all the gnt-* commands.
427 - commands: a dictionary with a special structure, see the design doc
428 for command line handling.
429 - override: if not None, we expect a dictionary with keys that will
430 override command line options; this can be used to pass
431 options from the scripts to generic functions
434 # save the program name and the entire command line for later logging
436 binary = os.path.basename(sys.argv[0]) or sys.argv[0]
437 if len(sys.argv) >= 2:
438 binary += " " + sys.argv[1]
439 old_cmdline = " ".join(sys.argv[2:])
443 binary = "<unknown program>"
446 func, options, args = _ParseArgs(sys.argv, commands)
447 if func is None: # parse error
450 if override is not None:
451 for key, val in override.iteritems():
452 setattr(options, key, val)
454 logger.SetupLogging(debug=options.debug, program=binary)
456 utils.debug = options.debug
458 utils.Lock('cmd', max_retries=options.lock_retries, debug=options.debug)
459 except errors.LockError, err:
460 logger.ToStderr(str(err))
464 logger.Info("run with arguments '%s'" % old_cmdline)
466 logger.Info("run with no arguments")
470 result = func(options, args)
471 except errors.GenericError, err:
472 result, err_msg = FormatError(err)
473 logger.ToStderr(err_msg)
481 def GenerateTable(headers, fields, separator, data,
482 numfields=None, unitfields=None):
483 """Prints a table with headers and different fields.
486 headers: Dict of header titles or None if no headers should be shown
487 fields: List of fields to show
488 separator: String used to separate fields or None for spaces
489 data: Data to be printed
490 numfields: List of fields to be aligned to right
491 unitfields: List of fields to be formatted as units
494 if numfields is None:
496 if unitfields is None:
501 if headers and field not in headers:
502 raise errors.ProgrammerError("Missing header description for field '%s'"
504 if separator is not None:
505 format_fields.append("%s")
506 elif field in numfields:
507 format_fields.append("%*s")
509 format_fields.append("%-*s")
511 if separator is None:
512 mlens = [0 for name in fields]
513 format = ' '.join(format_fields)
515 format = separator.replace("%", "%%").join(format_fields)
518 for idx, val in enumerate(row):
519 if fields[idx] in unitfields:
525 val = row[idx] = utils.FormatUnit(val)
526 val = row[idx] = str(val)
527 if separator is None:
528 mlens[idx] = max(mlens[idx], len(val))
533 for idx, name in enumerate(fields):
535 if separator is None:
536 mlens[idx] = max(mlens[idx], len(hdr))
537 args.append(mlens[idx])
539 result.append(format % tuple(args))
543 for idx in xrange(len(fields)):
544 if separator is None:
545 args.append(mlens[idx])
546 args.append(line[idx])
547 result.append(format % tuple(args))