From c29499f3185c5d7cf4749bd066820ad34c445762 Mon Sep 17 00:00:00 2001 From: Liam Young Date: Mon, 3 Aug 2015 15:52:53 +0100 Subject: [PATCH] [gnuoy,trivial] Pre-release charmhelper sync --- charm-helpers-hooks.yaml | 1 + hooks/charmhelpers/cli/__init__.py | 195 ++++++++++++++++++ hooks/charmhelpers/cli/benchmark.py | 36 ++++ hooks/charmhelpers/cli/commands.py | 32 +++ hooks/charmhelpers/cli/host.py | 31 +++ hooks/charmhelpers/cli/unitdata.py | 39 ++++ .../charmhelpers/contrib/openstack/context.py | 60 +++--- hooks/charmhelpers/core/files.py | 45 ++++ hooks/charmhelpers/core/hookenv.py | 121 ++++++++++- hooks/charmhelpers/core/unitdata.py | 78 +++++-- 10 files changed, 593 insertions(+), 45 deletions(-) create mode 100644 hooks/charmhelpers/cli/__init__.py create mode 100644 hooks/charmhelpers/cli/benchmark.py create mode 100644 hooks/charmhelpers/cli/commands.py create mode 100644 hooks/charmhelpers/cli/host.py create mode 100644 hooks/charmhelpers/cli/unitdata.py create mode 100644 hooks/charmhelpers/core/files.py diff --git a/charm-helpers-hooks.yaml b/charm-helpers-hooks.yaml index 84cc6c76..7fe56f46 100644 --- a/charm-helpers-hooks.yaml +++ b/charm-helpers-hooks.yaml @@ -2,6 +2,7 @@ branch: lp:charm-helpers destination: hooks/charmhelpers include: - core + - cli - fetch - contrib.openstack|inc=* - contrib.hahelpers diff --git a/hooks/charmhelpers/cli/__init__.py b/hooks/charmhelpers/cli/__init__.py new file mode 100644 index 00000000..7118daf5 --- /dev/null +++ b/hooks/charmhelpers/cli/__init__.py @@ -0,0 +1,195 @@ +# Copyright 2014-2015 Canonical Limited. +# +# This file is part of charm-helpers. +# +# charm-helpers is free software: you can redistribute it and/or modify +# it under the terms of the GNU Lesser General Public License version 3 as +# published by the Free Software Foundation. +# +# charm-helpers is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Lesser General Public License for more details. +# +# You should have received a copy of the GNU Lesser General Public License +# along with charm-helpers. If not, see . + +import inspect +import argparse +import sys + +from six.moves import zip + +from charmhelpers.core import unitdata + + +class OutputFormatter(object): + def __init__(self, outfile=sys.stdout): + self.formats = ( + "raw", + "json", + "py", + "yaml", + "csv", + "tab", + ) + self.outfile = outfile + + def add_arguments(self, argument_parser): + formatgroup = argument_parser.add_mutually_exclusive_group() + choices = self.supported_formats + formatgroup.add_argument("--format", metavar='FMT', + help="Select output format for returned data, " + "where FMT is one of: {}".format(choices), + choices=choices, default='raw') + for fmt in self.formats: + fmtfunc = getattr(self, fmt) + formatgroup.add_argument("-{}".format(fmt[0]), + "--{}".format(fmt), action='store_const', + const=fmt, dest='format', + help=fmtfunc.__doc__) + + @property + def supported_formats(self): + return self.formats + + def raw(self, output): + """Output data as raw string (default)""" + if isinstance(output, (list, tuple)): + output = '\n'.join(map(str, output)) + self.outfile.write(str(output)) + + def py(self, output): + """Output data as a nicely-formatted python data structure""" + import pprint + pprint.pprint(output, stream=self.outfile) + + def json(self, output): + """Output data in JSON format""" + import json + json.dump(output, self.outfile) + + def yaml(self, output): + """Output data in YAML format""" + import yaml + yaml.safe_dump(output, self.outfile) + + def csv(self, output): + """Output data as excel-compatible CSV""" + import csv + csvwriter = csv.writer(self.outfile) + csvwriter.writerows(output) + + def tab(self, output): + """Output data in excel-compatible tab-delimited format""" + import csv + csvwriter = csv.writer(self.outfile, dialect=csv.excel_tab) + csvwriter.writerows(output) + + def format_output(self, output, fmt='raw'): + fmtfunc = getattr(self, fmt) + fmtfunc(output) + + +class CommandLine(object): + argument_parser = None + subparsers = None + formatter = None + exit_code = 0 + + def __init__(self): + if not self.argument_parser: + self.argument_parser = argparse.ArgumentParser(description='Perform common charm tasks') + if not self.formatter: + self.formatter = OutputFormatter() + self.formatter.add_arguments(self.argument_parser) + if not self.subparsers: + self.subparsers = self.argument_parser.add_subparsers(help='Commands') + + def subcommand(self, command_name=None): + """ + Decorate a function as a subcommand. Use its arguments as the + command-line arguments""" + def wrapper(decorated): + cmd_name = command_name or decorated.__name__ + subparser = self.subparsers.add_parser(cmd_name, + description=decorated.__doc__) + for args, kwargs in describe_arguments(decorated): + subparser.add_argument(*args, **kwargs) + subparser.set_defaults(func=decorated) + return decorated + return wrapper + + def test_command(self, decorated): + """ + Subcommand is a boolean test function, so bool return values should be + converted to a 0/1 exit code. + """ + decorated._cli_test_command = True + return decorated + + def no_output(self, decorated): + """ + Subcommand is not expected to return a value, so don't print a spurious None. + """ + decorated._cli_no_output = True + return decorated + + def subcommand_builder(self, command_name, description=None): + """ + Decorate a function that builds a subcommand. Builders should accept a + single argument (the subparser instance) and return the function to be + run as the command.""" + def wrapper(decorated): + subparser = self.subparsers.add_parser(command_name) + func = decorated(subparser) + subparser.set_defaults(func=func) + subparser.description = description or func.__doc__ + return wrapper + + def run(self): + "Run cli, processing arguments and executing subcommands." + arguments = self.argument_parser.parse_args() + argspec = inspect.getargspec(arguments.func) + vargs = [] + kwargs = {} + for arg in argspec.args: + vargs.append(getattr(arguments, arg)) + if argspec.varargs: + vargs.extend(getattr(arguments, argspec.varargs)) + if argspec.keywords: + for kwarg in argspec.keywords.items(): + kwargs[kwarg] = getattr(arguments, kwarg) + output = arguments.func(*vargs, **kwargs) + if getattr(arguments.func, '_cli_test_command', False): + self.exit_code = 0 if output else 1 + output = '' + if getattr(arguments.func, '_cli_no_output', False): + output = '' + self.formatter.format_output(output, arguments.format) + if unitdata._KV: + unitdata._KV.flush() + + +cmdline = CommandLine() + + +def describe_arguments(func): + """ + Analyze a function's signature and return a data structure suitable for + passing in as arguments to an argparse parser's add_argument() method.""" + + argspec = inspect.getargspec(func) + # we should probably raise an exception somewhere if func includes **kwargs + if argspec.defaults: + positional_args = argspec.args[:-len(argspec.defaults)] + keyword_names = argspec.args[-len(argspec.defaults):] + for arg, default in zip(keyword_names, argspec.defaults): + yield ('--{}'.format(arg),), {'default': default} + else: + positional_args = argspec.args + + for arg in positional_args: + yield (arg,), {} + if argspec.varargs: + yield (argspec.varargs,), {'nargs': '*'} diff --git a/hooks/charmhelpers/cli/benchmark.py b/hooks/charmhelpers/cli/benchmark.py new file mode 100644 index 00000000..b23c16ce --- /dev/null +++ b/hooks/charmhelpers/cli/benchmark.py @@ -0,0 +1,36 @@ +# Copyright 2014-2015 Canonical Limited. +# +# This file is part of charm-helpers. +# +# charm-helpers is free software: you can redistribute it and/or modify +# it under the terms of the GNU Lesser General Public License version 3 as +# published by the Free Software Foundation. +# +# charm-helpers is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Lesser General Public License for more details. +# +# You should have received a copy of the GNU Lesser General Public License +# along with charm-helpers. If not, see . + +from . import cmdline +from charmhelpers.contrib.benchmark import Benchmark + + +@cmdline.subcommand(command_name='benchmark-start') +def start(): + Benchmark.start() + + +@cmdline.subcommand(command_name='benchmark-finish') +def finish(): + Benchmark.finish() + + +@cmdline.subcommand_builder('benchmark-composite', description="Set the benchmark composite score") +def service(subparser): + subparser.add_argument("value", help="The composite score.") + subparser.add_argument("units", help="The units the composite score represents, i.e., 'reads/sec'.") + subparser.add_argument("direction", help="'asc' if a lower score is better, 'desc' if a higher score is better.") + return Benchmark.set_composite_score diff --git a/hooks/charmhelpers/cli/commands.py b/hooks/charmhelpers/cli/commands.py new file mode 100644 index 00000000..443ff05d --- /dev/null +++ b/hooks/charmhelpers/cli/commands.py @@ -0,0 +1,32 @@ +# Copyright 2014-2015 Canonical Limited. +# +# This file is part of charm-helpers. +# +# charm-helpers is free software: you can redistribute it and/or modify +# it under the terms of the GNU Lesser General Public License version 3 as +# published by the Free Software Foundation. +# +# charm-helpers is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Lesser General Public License for more details. +# +# You should have received a copy of the GNU Lesser General Public License +# along with charm-helpers. If not, see . + +""" +This module loads sub-modules into the python runtime so they can be +discovered via the inspect module. In order to prevent flake8 from (rightfully) +telling us these are unused modules, throw a ' # noqa' at the end of each import +so that the warning is suppressed. +""" + +from . import CommandLine # noqa + +""" +Import the sub-modules which have decorated subcommands to register with chlp. +""" +import host # noqa +import benchmark # noqa +import unitdata # noqa +from charmhelpers.core import hookenv # noqa diff --git a/hooks/charmhelpers/cli/host.py b/hooks/charmhelpers/cli/host.py new file mode 100644 index 00000000..58e78d6b --- /dev/null +++ b/hooks/charmhelpers/cli/host.py @@ -0,0 +1,31 @@ +# Copyright 2014-2015 Canonical Limited. +# +# This file is part of charm-helpers. +# +# charm-helpers is free software: you can redistribute it and/or modify +# it under the terms of the GNU Lesser General Public License version 3 as +# published by the Free Software Foundation. +# +# charm-helpers is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Lesser General Public License for more details. +# +# You should have received a copy of the GNU Lesser General Public License +# along with charm-helpers. If not, see . + +from . import cmdline +from charmhelpers.core import host + + +@cmdline.subcommand() +def mounts(): + "List mounts" + return host.mounts() + + +@cmdline.subcommand_builder('service', description="Control system services") +def service(subparser): + subparser.add_argument("action", help="The action to perform (start, stop, etc...)") + subparser.add_argument("service_name", help="Name of the service to control") + return host.service diff --git a/hooks/charmhelpers/cli/unitdata.py b/hooks/charmhelpers/cli/unitdata.py new file mode 100644 index 00000000..d1cd95bf --- /dev/null +++ b/hooks/charmhelpers/cli/unitdata.py @@ -0,0 +1,39 @@ +# Copyright 2014-2015 Canonical Limited. +# +# This file is part of charm-helpers. +# +# charm-helpers is free software: you can redistribute it and/or modify +# it under the terms of the GNU Lesser General Public License version 3 as +# published by the Free Software Foundation. +# +# charm-helpers is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Lesser General Public License for more details. +# +# You should have received a copy of the GNU Lesser General Public License +# along with charm-helpers. If not, see . + +from . import cmdline +from charmhelpers.core import unitdata + + +@cmdline.subcommand_builder('unitdata', description="Store and retrieve data") +def unitdata_cmd(subparser): + nested = subparser.add_subparsers() + get_cmd = nested.add_parser('get', help='Retrieve data') + get_cmd.add_argument('key', help='Key to retrieve the value of') + get_cmd.set_defaults(action='get', value=None) + set_cmd = nested.add_parser('set', help='Store data') + set_cmd.add_argument('key', help='Key to set') + set_cmd.add_argument('value', help='Value to store') + set_cmd.set_defaults(action='set') + + def _unitdata_cmd(action, key, value): + if action == 'get': + return unitdata.kv().get(key) + elif action == 'set': + unitdata.kv().set(key, value) + unitdata.kv().flush() + return '' + return _unitdata_cmd diff --git a/hooks/charmhelpers/contrib/openstack/context.py b/hooks/charmhelpers/contrib/openstack/context.py index 8f3f1b15..ab2ebac1 100644 --- a/hooks/charmhelpers/contrib/openstack/context.py +++ b/hooks/charmhelpers/contrib/openstack/context.py @@ -1051,13 +1051,22 @@ class SubordinateConfigContext(OSContextGenerator): :param config_file : Service's config file to query sections :param interface : Subordinate interface to inspect """ - self.service = service self.config_file = config_file - self.interface = interface + if isinstance(service, list): + self.services = service + else: + self.services = [service] + if isinstance(interface, list): + self.interfaces = interface + else: + self.interfaces = [interface] def __call__(self): ctxt = {'sections': {}} - for rid in relation_ids(self.interface): + rids = [] + for interface in self.interfaces: + rids.extend(relation_ids(interface)) + for rid in rids: for unit in related_units(rid): sub_config = relation_get('subordinate_configuration', rid=rid, unit=unit) @@ -1069,29 +1078,32 @@ class SubordinateConfigContext(OSContextGenerator): 'setting from %s' % rid, level=ERROR) continue - if self.service not in sub_config: - log('Found subordinate_config on %s but it contained' - 'nothing for %s service' % (rid, self.service), - level=INFO) - continue + for service in self.services: + if service not in sub_config: + log('Found subordinate_config on %s but it contained' + 'nothing for %s service' % (rid, service), + level=INFO) + continue - sub_config = sub_config[self.service] - if self.config_file not in sub_config: - log('Found subordinate_config on %s but it contained' - 'nothing for %s' % (rid, self.config_file), - level=INFO) - continue - - sub_config = sub_config[self.config_file] - for k, v in six.iteritems(sub_config): - if k == 'sections': - for section, config_dict in six.iteritems(v): - log("adding section '%s'" % (section), - level=DEBUG) - ctxt[k][section] = config_dict - else: - ctxt[k] = v + sub_config = sub_config[service] + if self.config_file not in sub_config: + log('Found subordinate_config on %s but it contained' + 'nothing for %s' % (rid, self.config_file), + level=INFO) + continue + sub_config = sub_config[self.config_file] + for k, v in six.iteritems(sub_config): + if k == 'sections': + for section, config_list in six.iteritems(v): + log("adding section '%s'" % (section), + level=DEBUG) + if ctxt[k].get(section): + ctxt[k][section].extend(config_list) + else: + ctxt[k][section] = config_list + else: + ctxt[k] = v log("%d section(s) found" % (len(ctxt['sections'])), level=DEBUG) return ctxt diff --git a/hooks/charmhelpers/core/files.py b/hooks/charmhelpers/core/files.py new file mode 100644 index 00000000..0f12d321 --- /dev/null +++ b/hooks/charmhelpers/core/files.py @@ -0,0 +1,45 @@ +#!/usr/bin/env python +# -*- coding: utf-8 -*- + +# Copyright 2014-2015 Canonical Limited. +# +# This file is part of charm-helpers. +# +# charm-helpers is free software: you can redistribute it and/or modify +# it under the terms of the GNU Lesser General Public License version 3 as +# published by the Free Software Foundation. +# +# charm-helpers is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU Lesser General Public License for more details. +# +# You should have received a copy of the GNU Lesser General Public License +# along with charm-helpers. If not, see . + +__author__ = 'Jorge Niedbalski ' + +import os +import subprocess + + +def sed(filename, before, after, flags='g'): + """ + Search and replaces the given pattern on filename. + + :param filename: relative or absolute file path. + :param before: expression to be replaced (see 'man sed') + :param after: expression to replace with (see 'man sed') + :param flags: sed-compatible regex flags in example, to make + the search and replace case insensitive, specify ``flags="i"``. + The ``g`` flag is always specified regardless, so you do not + need to remember to include it when overriding this parameter. + :returns: If the sed command exit code was zero then return, + otherwise raise CalledProcessError. + """ + expression = r's/{0}/{1}/{2}'.format(before, + after, flags) + + return subprocess.check_call(["sed", "-i", "-r", "-e", + expression, + os.path.expanduser(filename)]) diff --git a/hooks/charmhelpers/core/hookenv.py b/hooks/charmhelpers/core/hookenv.py index 15b09d11..18860f59 100644 --- a/hooks/charmhelpers/core/hookenv.py +++ b/hooks/charmhelpers/core/hookenv.py @@ -34,6 +34,23 @@ import errno import tempfile from subprocess import CalledProcessError +try: + from charmhelpers.cli import cmdline +except ImportError as e: + # due to the anti-pattern of partially synching charmhelpers directly + # into charms, it's possible that charmhelpers.cli is not available; + # if that's the case, they don't really care about using the cli anyway, + # so mock it out + if str(e) == 'No module named cli': + class cmdline(object): + @classmethod + def subcommand(cls, *args, **kwargs): + def _wrap(func): + return func + return _wrap + else: + raise + import six if not six.PY3: from UserDict import UserDict @@ -173,9 +190,20 @@ def relation_type(): return os.environ.get('JUJU_RELATION', None) -def relation_id(): - """The relation ID for the current relation hook""" - return os.environ.get('JUJU_RELATION_ID', None) +@cmdline.subcommand() +@cached +def relation_id(relation_name=None, service_or_unit=None): + """The relation ID for the current or a specified relation""" + if not relation_name and not service_or_unit: + return os.environ.get('JUJU_RELATION_ID', None) + elif relation_name and service_or_unit: + service_name = service_or_unit.split('/')[0] + for relid in relation_ids(relation_name): + remote_service = remote_service_name(relid) + if remote_service == service_name: + return relid + else: + raise ValueError('Must specify neither or both of relation_name and service_or_unit') def local_unit(): @@ -188,14 +216,27 @@ def remote_unit(): return os.environ.get('JUJU_REMOTE_UNIT', None) +@cmdline.subcommand() def service_name(): """The name service group this unit belongs to""" return local_unit().split('/')[0] +@cmdline.subcommand() +@cached +def remote_service_name(relid=None): + """The remote service name for a given relation-id (or the current relation)""" + if relid is None: + unit = remote_unit() + else: + units = related_units(relid) + unit = units[0] if units else None + return unit.split('/')[0] if unit else None + + def hook_name(): """The name of the currently executing hook""" - return os.path.basename(sys.argv[0]) + return os.environ.get('JUJU_HOOK_NAME', os.path.basename(sys.argv[0])) class Config(dict): @@ -468,6 +509,63 @@ def relation_types(): return rel_types +@cached +def relation_to_interface(relation_name): + """ + Given the name of a relation, return the interface that relation uses. + + :returns: The interface name, or ``None``. + """ + return relation_to_role_and_interface(relation_name)[1] + + +@cached +def relation_to_role_and_interface(relation_name): + """ + Given the name of a relation, return the role and the name of the interface + that relation uses (where role is one of ``provides``, ``requires``, or ``peer``). + + :returns: A tuple containing ``(role, interface)``, or ``(None, None)``. + """ + _metadata = metadata() + for role in ('provides', 'requires', 'peer'): + interface = _metadata.get(role, {}).get(relation_name, {}).get('interface') + if interface: + return role, interface + return None, None + + +@cached +def role_and_interface_to_relations(role, interface_name): + """ + Given a role and interface name, return a list of relation names for the + current charm that use that interface under that role (where role is one + of ``provides``, ``requires``, or ``peer``). + + :returns: A list of relation names. + """ + _metadata = metadata() + results = [] + for relation_name, relation in _metadata.get(role, {}).items(): + if relation['interface'] == interface_name: + results.append(relation_name) + return results + + +@cached +def interface_to_relations(interface_name): + """ + Given an interface, return a list of relation names for the current + charm that use that interface. + + :returns: A list of relation names. + """ + results = [] + for role in ('provides', 'requires', 'peer'): + results.extend(role_and_interface_to_relations(role, interface_name)) + return results + + @cached def charm_name(): """Get the name of the current charm as is specified on metadata.yaml""" @@ -644,6 +742,21 @@ def action_fail(message): subprocess.check_call(['action-fail', message]) +def action_name(): + """Get the name of the currently executing action.""" + return os.environ.get('JUJU_ACTION_NAME') + + +def action_uuid(): + """Get the UUID of the currently executing action.""" + return os.environ.get('JUJU_ACTION_UUID') + + +def action_tag(): + """Get the tag for the currently executing action.""" + return os.environ.get('JUJU_ACTION_TAG') + + def status_set(workload_state, message): """Set the workload state with a message diff --git a/hooks/charmhelpers/core/unitdata.py b/hooks/charmhelpers/core/unitdata.py index 406a35c5..338104e0 100644 --- a/hooks/charmhelpers/core/unitdata.py +++ b/hooks/charmhelpers/core/unitdata.py @@ -152,6 +152,7 @@ associated to the hookname. import collections import contextlib import datetime +import itertools import json import os import pprint @@ -164,8 +165,7 @@ __author__ = 'Kapil Thangavelu ' class Storage(object): """Simple key value database for local unit state within charms. - Modifications are automatically committed at hook exit. That's - currently regardless of exit code. + Modifications are not persisted unless :meth:`flush` is called. To support dicts, lists, integer, floats, and booleans values are automatically json encoded/decoded. @@ -173,8 +173,11 @@ class Storage(object): def __init__(self, path=None): self.db_path = path if path is None: - self.db_path = os.path.join( - os.environ.get('CHARM_DIR', ''), '.unit-state.db') + if 'UNIT_STATE_DB' in os.environ: + self.db_path = os.environ['UNIT_STATE_DB'] + else: + self.db_path = os.path.join( + os.environ.get('CHARM_DIR', ''), '.unit-state.db') self.conn = sqlite3.connect('%s' % self.db_path) self.cursor = self.conn.cursor() self.revision = None @@ -189,15 +192,8 @@ class Storage(object): self.conn.close() self._closed = True - def _scoped_query(self, stmt, params=None): - if params is None: - params = [] - return stmt, params - def get(self, key, default=None, record=False): - self.cursor.execute( - *self._scoped_query( - 'select data from kv where key=?', [key])) + self.cursor.execute('select data from kv where key=?', [key]) result = self.cursor.fetchone() if not result: return default @@ -206,33 +202,81 @@ class Storage(object): return json.loads(result[0]) def getrange(self, key_prefix, strip=False): - stmt = "select key, data from kv where key like '%s%%'" % key_prefix - self.cursor.execute(*self._scoped_query(stmt)) + """ + Get a range of keys starting with a common prefix as a mapping of + keys to values. + + :param str key_prefix: Common prefix among all keys + :param bool strip: Optionally strip the common prefix from the key + names in the returned dict + :return dict: A (possibly empty) dict of key-value mappings + """ + self.cursor.execute("select key, data from kv where key like ?", + ['%s%%' % key_prefix]) result = self.cursor.fetchall() if not result: - return None + return {} if not strip: key_prefix = '' return dict([ (k[len(key_prefix):], json.loads(v)) for k, v in result]) def update(self, mapping, prefix=""): + """ + Set the values of multiple keys at once. + + :param dict mapping: Mapping of keys to values + :param str prefix: Optional prefix to apply to all keys in `mapping` + before setting + """ for k, v in mapping.items(): self.set("%s%s" % (prefix, k), v) def unset(self, key): + """ + Remove a key from the database entirely. + """ self.cursor.execute('delete from kv where key=?', [key]) if self.revision and self.cursor.rowcount: self.cursor.execute( 'insert into kv_revisions values (?, ?, ?)', [key, self.revision, json.dumps('DELETED')]) + def unsetrange(self, keys=None, prefix=""): + """ + Remove a range of keys starting with a common prefix, from the database + entirely. + + :param list keys: List of keys to remove. + :param str prefix: Optional prefix to apply to all keys in ``keys`` + before removing. + """ + if keys is not None: + keys = ['%s%s' % (prefix, key) for key in keys] + self.cursor.execute('delete from kv where key in (%s)' % ','.join(['?'] * len(keys)), keys) + if self.revision and self.cursor.rowcount: + self.cursor.execute( + 'insert into kv_revisions values %s' % ','.join(['(?, ?, ?)'] * len(keys)), + list(itertools.chain.from_iterable((key, self.revision, json.dumps('DELETED')) for key in keys))) + else: + self.cursor.execute('delete from kv where key like ?', + ['%s%%' % prefix]) + if self.revision and self.cursor.rowcount: + self.cursor.execute( + 'insert into kv_revisions values (?, ?, ?)', + ['%s%%' % prefix, self.revision, json.dumps('DELETED')]) + def set(self, key, value): + """ + Set a value in the database. + + :param str key: Key to set the value for + :param value: Any JSON-serializable value to be set + """ serialized = json.dumps(value) - self.cursor.execute( - 'select data from kv where key=?', [key]) + self.cursor.execute('select data from kv where key=?', [key]) exists = self.cursor.fetchone() # Skip mutations to the same value