debian-koji/kojihub/kojixmlrpc.py

# kojixmlrpc - an XMLRPC interface for koji.
# Copyright (c) 2005-2014 Red Hat, Inc.
#
#    Koji is free software; you can redistribute it and/or
#    modify it under the terms of the GNU Lesser General Public
#    License as published by the Free Software Foundation;
#    version 2.1 of the License.
#
#    This software 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 this software; if not, write to the Free Software
#    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
#
# Authors:
#       Mike McLean <mikem@redhat.com>

import datetime
import inspect
import logging
import os
import pprint
import resource
import sys
import threading
import time
import traceback
import re

import koji
import koji.plugin
import koji.policy
import koji.util
import kojihub
from koji.context import context
# import xmlrpclib functions from koji to use tweaked Marshaller
from koji.server import ServerError, BadRequest, RequestTimeout
from koji.xmlrpcplus import ExtendedMarshaller, Fault, dumps, getparser
from . import auth
from . import db
from . import scheduler
from . import repos


# HTTP headers included in every request
GLOBAL_HEADERS = [
    ('Koji-Version', koji.__version__),
]


class Marshaller(ExtendedMarshaller):

    dispatch = ExtendedMarshaller.dispatch.copy()

    def dump_datetime(self, value, write):
        # For backwards compatibility, we return datetime objects as strings
        value = value.isoformat(' ')
        self.dump_unicode(value, write)
    dispatch[datetime.datetime] = dump_datetime


class HandlerRegistry(object):
    """Track handlers for RPC calls"""

    def __init__(self):
        self.funcs = {}
        # introspection functions
        self.register_function(self.list_api, name="_listapi")
        self.register_function(self.system_listMethods, name="system.listMethods")
        self.register_function(self.system_methodSignature, name="system.methodSignature")
        self.register_function(self.system_methodHelp, name="system.methodHelp")
        self.argspec_cache = {}

    def register_function(self, function, name=None):
        if name is None:
            name = function.__name__
        self.funcs[name] = function

    def register_module(self, instance, prefix=None):
        """Register all the public functions in an instance with prefix prepended

        For example
            h.register_module(exports,"pub.sys")
        will register the methods of exports with names like
            pub.sys.method1
            pub.sys.method2
            ...etc
        """
        for name in dir(instance):
            if name.startswith('_'):
                continue
            function = getattr(instance, name)
            if not callable(function):
                continue
            if prefix is not None:
                name = "%s.%s" % (prefix, name)
            self.register_function(function, name=name)

    def register_instance(self, instance):
        self.register_module(instance)

    def register_plugin(self, plugin):
        """Scan a given plugin for handlers

        Handlers are functions marked with one of the decorators defined in koji.plugin
        """
        for v in vars(plugin).values():
            if isinstance(v, type):
                # skip classes
                continue
            if callable(v):
                if getattr(v, 'exported', False):
                    if hasattr(v, 'export_alias'):
                        name = getattr(v, 'export_alias')
                    else:
                        name = v.__name__
                    self.register_function(v, name=name)
                if getattr(v, 'callbacks', None):
                    for cbtype in v.callbacks:
                        koji.plugin.register_callback(cbtype, v)

    def getargspec(self, func):
        ret = self.argspec_cache.get(func)
        if ret:
            return ret
        ret = tuple(inspect.getfullargspec(func))
        if inspect.ismethod(func) and func.__self__:
            # bound method, remove first arg
            args, varargs, varkw, defaults, kwonlyargs, kwonlydefaults, ann = ret
            if args:
                aname = args[0]  # generally "self"
                del args[0]
                if defaults and aname in defaults:
                    # shouldn't happen, but...
                    del defaults[aname]
        self.argspec_cache[func] = ret
        return ret

    def list_api(self):
        """List available API calls"""
        funcs = []
        for name, func in self.funcs.items():
            # the keys in self.funcs determine the name of the method as seen over xmlrpc
            # func.__name__ might differ (e.g. for dotted method names)
            sig = inspect.signature(func)
            args = []
            argdesc = []
            for pname, param in sig.parameters.items():
                if param.default != param.empty:
                    args.append([pname, param.default])
                else:
                    args.append(pname)
            argdesc = '(%s)' % ', '.join([str(x) for x in sig.parameters.values()])
            argspec = self.getargspec(func)
            funcs.append({'name': name,
                          'doc': func.__doc__,
                          'argspec': argspec,
                          'argdesc': argdesc,
                          'args': args})
        return funcs

    def system_listMethods(self):
        return list(self.funcs.keys())

    def system_methodSignature(self, method):
        # it is not possible to autogenerate this data
        return 'signatures not supported'

    def system_methodHelp(self, method):
        func = self.funcs.get(method)
        if func is None:
            return ""
        sig = inspect.signature(func)
        args = ', '.join([str(x) for x in sig.parameters.values()])
        ret = f'{method}({args})'
        if func.__doc__:
            ret += f'\ndescription: {func.__doc__}'
        return ret

    def get(self, name):
        func = self.funcs.get(name, None)
        if func is None:
            raise koji.GenericError("Invalid method: %s" % name)
        return func


class HandlerAccess(object):
    """This class is used to grant access to the rpc handlers"""

    def __init__(self, registry):
        self.__reg = registry

    def call(self, __name, *args, **kwargs):
        return self.__reg.get(__name)(*args, **kwargs)

    def get(self, name):
        return self.__reg.get(name)


class ModXMLRPCRequestHandler(object):
    """Simple XML-RPC handler for mod_wsgi environment"""

    def __init__(self, handlers):
        self.traceback = False
        self.handlers = handlers  # expecting HandlerRegistry instance
        self.logger = logging.getLogger('koji.xmlrpc')

    def _get_handler(self, name):
        # just a wrapper so we can handle multicall ourselves
        # we don't register multicall since the registry will outlive our instance
        if name in ('multiCall', 'system.multicall'):
            return self.multiCall
        else:
            return self.handlers.get(name)

    def _read_request(self, stream):
        parser, unmarshaller = getparser()
        rlen = 0
        maxlen = opts.get('MaxRequestLength', None)
        while True:
            try:
                chunk = stream.read(8192)
            except OSError as e:
                str_e = str(e)
                if 'timeout' in str_e:
                    self.logger.exception("Timed out reading input stream. Content-Length: "
                                          f"{context.environ.get('CONTENT_LENGTH')}")
                    raise RequestTimeout(str_e)
                else:
                    self.logger.exception("Error reading input stream. Content-Length: "
                                          f"{context.environ.get('CONTENT_LENGTH')}")
                    raise BadRequest(str_e)
            if not chunk:
                break
            rlen += len(chunk)
            if maxlen and rlen > maxlen:
                raise koji.GenericError('Request too long')
            parser.feed(chunk)
        parser.close()
        return unmarshaller.close(), unmarshaller.getmethodname()

    def _log_exception(self):
        e_class, e = sys.exc_info()[:2]
        faultCode = getattr(e_class, 'faultCode', 1)
        tb_type = context.opts.get('KojiTraceback', None)
        tb_str = ''.join(traceback.format_exception(*sys.exc_info()))
        if issubclass(e_class, koji.GenericError):
            if context.opts.get('KojiDebug'):
                if tb_type == "extended":
                    faultString = koji.format_exc_plus()
                else:
                    faultString = tb_str
            else:
                faultString = str(e)
        else:
            if tb_type == "normal":
                faultString = tb_str
            elif tb_type == "extended":
                faultString = koji.format_exc_plus()
            else:
                faultString = "%s: %s" % (e_class, e)
        self.logger.warning(tb_str)
        return faultCode, faultString

    def _wrap_handler(self, handler, environ):
        """Catch exceptions and encode response of handler"""

        # generate response
        try:
            response = handler(environ)
            # wrap response in a singleton tuple
            response = (response,)
            response = dumps(response, methodresponse=1, marshaller=Marshaller)
        except ServerError:
            raise
            # these are handled higher up
        except Fault as fault:
            self.traceback = True
            response = dumps(fault, marshaller=Marshaller)
        except Exception:
            self.traceback = True
            # report exception back to server
            faultCode, faultString = self._log_exception()
            response = dumps(Fault(faultCode, faultString), marshaller=Marshaller)

        return response

    def handle_upload(self, environ):
        # uploads can't be in a multicall
        context.method = None
        self.check_session()
        self.enforce_lockout()
        return kojihub.handle_upload(environ)

    def handle_rpc(self, environ):
        params, method = self._read_request(environ['wsgi.input'])
        return self._dispatch(method, params)

    def check_session(self):
        if not hasattr(context, "session"):
            # we may be called again by one of our meta-calls (like multiCall)
            # so we should only create a session if one does not already exist
            context.session = auth.Session()
            try:
                context.session.validate()
            except koji.AuthLockError:
                # might be ok, depending on method
                if context.method not in ('exclusiveSession', 'login', 'logout'):
                    raise

    def enforce_lockout(self):
        if context.opts.get('LockOut') and \
                context.method not in ('login', 'sslLogin', 'logout') and \
                not context.session.hasPerm('admin'):
            raise koji.ServerOffline("Server disabled for maintenance")

    def _dispatch(self, method, params):
        func = self._get_handler(method)
        context.method = method
        context.params = params
        self.check_session()
        self.enforce_lockout()
        # handle named parameters
        params, opts = koji.decode_args(*params)

        if self.logger.isEnabledFor(logging.INFO):
            self.logger.info("Handling method %s for session %s (#%s)",
                             method, context.session.id, context.session.callnum)
            if method != 'uploadFile' and self.logger.isEnabledFor(logging.DEBUG):
                self.logger.debug("Params: %s", pprint.pformat(params))
                self.logger.debug("Opts: %s", pprint.pformat(opts))
            start = time.time()

        ret = koji.util.call_with_argcheck(func, params, opts)

        if self.logger.isEnabledFor(logging.INFO):
            rusage = resource.getrusage(resource.RUSAGE_SELF)
            self.logger.info(
                "Completed method %s for session %s (#%s): %f seconds, rss %s, stime %f",
                method, context.session.id, context.session.callnum,
                time.time() - start,
                rusage.ru_maxrss, rusage.ru_stime)

        return ret

    def multiCall(self, calls):
        """Execute a multicall.  Execute each method call in the calls list, collecting
        results and errors, and return those as a list."""
        results = []
        for call in calls:
            savepoint = db.Savepoint('multiCall_loop')
            try:
                result = self._dispatch(call['methodName'], call['params'])
            except Fault as fault:
                savepoint.rollback()
                results.append({'faultCode': fault.faultCode, 'faultString': fault.faultString})
            except Exception:
                savepoint.rollback()
                # transform unknown exceptions into XML-RPC Faults
                # don't create a reference to full traceback since this creates
                # a circular reference.
                exc_type, exc_value = sys.exc_info()[:2]
                faultCode = getattr(exc_type, 'faultCode', 1)
                faultString = ', '.join([str(arg) for arg in exc_value.args])
                trace = traceback.format_exception(*sys.exc_info())
                # traceback is not part of the multicall spec,
                # but we include it for debugging purposes
                results.append({'faultCode': faultCode,
                                'faultString': faultString,
                                'traceback': trace})
                self._log_exception()
            else:
                results.append([result])

            # subsequent calls should not recycle event ids
            if hasattr(context, 'event_id'):
                del context.event_id

        return results

    def handle_request(self, req):
        """Handle a single XML-RPC request"""

        pass
        # XXX no longer used


def offline_reply(start_response, msg=None):
    """Send a ServerOffline reply"""
    faultCode = koji.ServerOffline.faultCode
    if msg is None:
        faultString = "server is offline"
    else:
        faultString = msg
    response = dumps(Fault(faultCode, faultString)).encode()
    headers = GLOBAL_HEADERS + [
        ('Content-Length', str(len(response))),
        ('Content-Type', "text/xml"),
    ]
    start_response('200 OK', headers)
    return [response]


def error_reply(start_response, status, response, extra_headers=None):
    response = response.encode()
    headers = GLOBAL_HEADERS + [
        ('Content-Length', str(len(response))),
        ('Content-Type', "text/plain"),
    ]
    if extra_headers:
        headers.extend(extra_headers)
    start_response(status, headers)
    return [response]


def load_config(environ):
    """Load configuration options

    Options are read from a config file. The config file location is
    controlled by the koji.hub.ConfigFile environment variable
    in the httpd config. To override this (for example):

      SetEnv koji.hub.ConfigFile /home/developer/koji/hub/hub.conf

    Backwards compatibility:
        - if ConfigFile is not set, opts are loaded from http config
        - if ConfigFile is set, then the http config must not provide Koji options
        - In a future version we will load the default hub config regardless
        - all PythonOptions (except ConfigFile) are now deprecated and support for them
          will disappear in a future version of Koji
    """
    # get our config file(s)
    cf = environ.get('koji.hub.ConfigFile', '/etc/koji-hub/hub.conf')
    cfdir = environ.get('koji.hub.ConfigDir', '/etc/koji-hub/hub.conf.d')
    config = koji.read_config_files([cfdir, (cf, True)], raw=True)

    cfgmap = [
        # option, type, default
        ['DBName', 'string', None],
        ['DBUser', 'string', None],
        ['DBHost', 'string', None],
        ['DBhost', 'string', None],   # alias for backwards compatibility
        ['DBPort', 'integer', None],
        ['DBPass', 'string', None],
        ['DBConnectionString', 'string', None],
        ['KojiDir', 'string', None],

        ['ProxyPrincipals', 'string', ''],
        ['HostPrincipalFormat', 'string', None],
        ['AllowedKrbRealms', 'string', '*'],
        # TODO:  this option should be turned True in 1.34
        ['DisableURLSessions', 'boolean', False],

        ['DNUsernameComponent', 'string', 'CN'],
        ['ProxyDNs', 'string', ''],

        ['CheckClientIP', 'boolean', True],

        ['LoginCreatesUser', 'boolean', True],
        ['AllowProxyAuthType', 'boolean', False],
        ['KojiWebURL', 'string', 'http://localhost.localdomain/koji'],
        ['EmailDomain', 'string', None],
        ['NotifyOnSuccess', 'boolean', True],
        ['DisableNotifications', 'boolean', False],

        ['Plugins', 'string', ''],
        ['PluginPath', 'string', '/usr/lib/koji-hub-plugins'],

        ['KojiDebug', 'boolean', False],
        ['KojiTraceback', 'string', None],
        ['VerbosePolicy', 'boolean', False],

        ['LogLevel', 'string', 'WARNING'],
        ['LogFormat', 'string',
         '%(asctime)s [%(levelname)s] m=%(method)s u=%(user_name)s p=%(process)s r=%(remoteaddr)s '
         '%(name)s: %(message)s'],

        ['MissingPolicyOk', 'boolean', True],
        ['EnableMaven', 'boolean', False],
        ['EnableWin', 'boolean', False],

        ['RLIMIT_AS', 'string', None],
        ['RLIMIT_CORE', 'string', None],
        ['RLIMIT_CPU', 'string', None],
        ['RLIMIT_DATA', 'string', None],
        ['RLIMIT_FSIZE', 'string', None],
        ['RLIMIT_MEMLOCK', 'string', None],
        ['RLIMIT_NOFILE', 'string', None],
        ['RLIMIT_NPROC', 'string', None],
        ['RLIMIT_OFILE', 'string', None],  # alias for RLIMIT_NOFILE
        ['RLIMIT_RSS', 'string', None],
        ['RLIMIT_STACK', 'string', None],

        ['MemoryWarnThreshold', 'integer', 5000],
        ['MaxRequestLength', 'integer', 4194304],

        ['LockOut', 'boolean', False],
        ['ServerOffline', 'boolean', False],
        ['OfflineMessage', 'string', None],

        ['MaxNameLengthInternal', 'integer', 256],
        ['RegexNameInternal', 'string', r'^[A-Za-z0-9/_.+-]+$'],
        ['RegexUserName', 'string', r'^[A-Za-z0-9/_.@-]+$'],

        ['RPMDefaultChecksums', 'string', 'md5 sha256'],

        ['SessionRenewalTimeout', 'integer', 1440],

        # scheduler options
        ['MaxJobs', 'integer', 15],
        ['CapacityOvercommit', 'integer', 5],
        ['ReadyTimeout', 'integer', 180],
        ['AssignTimeout', 'integer', 300],
        ['SoftRefusalTimeout', 'integer', 900],
        ['HostTimeout', 'integer', 900],
        ['RunInterval', 'integer', 60],

        # repo options
        ['MaxRepoTasks', 'integer', 10],
        ['MaxRepoTasksMaven', 'integer', 2],
        ['RepoRetries', 'integer', 3],
        ['RequestCleanTime', 'integer', 60 * 24],  # in minutes
        ['AllowNewRepo', 'bool', True],
        ['RepoLag', 'int', 3600],
        ['RepoAutoLag', 'int', 7200],
        ['RepoLagWindow', 'int', 600],
        ['RepoQueueUser', 'str', 'kojira'],
        ['DebuginfoTags', 'str', ''],
        ['SourceTags', 'str', ''],
        ['SeparateSourceTags', 'str', ''],
    ]
    opts = {}
    for name, dtype, default in cfgmap:
        key = ('hub', name)
        if config and config.has_option(*key):
            if dtype == 'integer':
                opts[name] = config.getint(*key)
            elif dtype == 'boolean':
                opts[name] = config.getboolean(*key)
            else:
                opts[name] = config.get(*key)
            continue
        opts[name] = default
    if opts['DBHost'] is None:
        opts['DBHost'] = opts['DBhost']
    if opts['RLIMIT_NOFILE'] is None:
        opts['RLIMIT_NOFILE'] = opts['RLIMIT_OFILE']
    # load policies
    # (only from config file)
    if config and config.has_section('policy'):
        # for the moment, we simply transfer the policy conf to opts
        opts['policy'] = dict(config.items('policy'))
    else:
        opts['policy'] = {}
    for pname, text in _default_policies.items():
        opts['policy'].setdefault(pname, text)
    # use configured KojiDir
    if opts.get('KojiDir') is not None:
        koji.BASEDIR = opts['KojiDir']
        koji.pathinfo.topdir = opts['KojiDir']
    if opts['RegexNameInternal'] != '':
        opts['RegexNameInternal.compiled'] = re.compile(opts['RegexNameInternal'])
    if opts['RegexUserName'] != '':
        opts['RegexUserName.compiled'] = re.compile(opts['RegexUserName'])

    return opts


def load_plugins(opts):
    """Load plugins specified by our configuration"""
    if not opts['Plugins']:
        return
    logger = logging.getLogger('koji.plugins')
    tracker = koji.plugin.PluginTracker(path=opts['PluginPath'].split(':'))
    for name in opts['Plugins'].split():
        logger.info('Loading plugin: %s', name)
        try:
            tracker.load(name)
        except Exception:
            logger.error(''.join(traceback.format_exception(*sys.exc_info())))
            # make this non-fatal, but set ServerOffline
            opts['ServerOffline'] = True
            opts['OfflineMessage'] = 'configuration error'
    return tracker


_default_policies = {
    'build_rpm': '''
            all :: allow
            ''',
    'build_from_srpm': '''
            has_perm admin :: allow
            all :: deny Only admin can do this via default policy
            ''',
    'build_from_repo_id': '''
            has_perm admin :: allow
            all :: deny Only admin can do this via default policy
            ''',
    'build_from_scm': '''
            has_perm admin :: allow
            # match scm_type CVS CVS+SSH && match scm_host scm.example.com && match scm_repository /cvs/example :: allow
            # match scm_type GIT GIT+SSH && match scm_host git.example.org && match scm_repository /example :: allow
            # match scm_type SVN SVN+SSH && match scm_host svn.example.org && match scm_repository /users/* :: allow
            all :: deny Only admin can do this via default policy
            ''',  # noqa: E501
    'package_list': '''
            has_perm admin :: allow
            has_perm tag :: allow
            all :: deny Only admin/tag can do this via default policy
            ''',
    'channel': '''
            has req_channel :: req
            is_child_task :: parent
            all :: use default
            ''',
    'vm': '''
            has_perm admin win-admin :: allow
            all :: deny Only admin/win-admin can do this via default policy
           ''',
    'cg_import': '''
            all :: allow
            ''',
    'volume': '''
            all :: DEFAULT
            ''',
    'priority': '''
            all :: stay
            ''',
    'draft_promotion': '''
            has_perm draft-promoter :: allow
            is_build_owner :: allow
            all :: deny Only draft-promoter and build owner can do this via default policy
            '''
}


def get_policy(opts, plugins):
    if not opts.get('policy'):
        return
    # first find available policy tests
    alltests = [koji.policy.findSimpleTests([vars(kojihub), vars(koji.policy)])]
    # we delay merging these to allow a test to be overridden for a specific policy
    for plugin_name in opts.get('Plugins', '').split():
        plugin = plugins.get(plugin_name)
        if not plugin:
            continue
        alltests.append(koji.policy.findSimpleTests(vars(plugin)))
    policy = {}
    for pname, text in opts['policy'].items():
        # filter/merge tests
        merged = {}
        for tests in alltests:
            # tests can be limited to certain policies by setting a class variable
            for name, test in tests.items():
                if hasattr(test, 'policy'):
                    if isinstance(test.policy, str):
                        if pname != test.policy:
                            continue
                    elif pname not in test.policy:
                        continue
                # in case of name overlap, last one wins
                # hence plugins can override builtin tests
                merged[name] = test
        policy[pname] = koji.policy.SimpleRuleSet(text.splitlines(), merged)
    return policy


class HubFormatter(logging.Formatter):
    """Support some koji specific fields in the format string"""

    def format(self, record):
        record.method = getattr(context, 'method', None)
        if hasattr(context, 'environ'):
            record.remoteaddr = "%s:%s" % (
                context.environ.get('REMOTE_ADDR', '?'),
                context.environ.get('REMOTE_PORT', '?'))
        else:
            record.remoteaddr = "?:?"
        if hasattr(context, 'session'):
            record.user_id = context.session.user_id
            record.session_id = context.session.id
            record.callnum = context.session.callnum
            record.user_name = context.session.user_data.get('name')
        else:
            record.user_id = None
            record.session_id = None
            record.callnum = None
            record.user_name = None
        return logging.Formatter.format(self, record)


def setup_logging1():
    """Set up basic logging, before options are loaded"""
    global log_handler
    logger = logging.getLogger("koji")
    logger.setLevel(logging.WARNING)
    # stderr logging (stderr goes to httpd logs)
    log_handler = logging.StreamHandler()
    log_format = '%(asctime)s [%(levelname)s] SETUP p=%(process)s %(name)s: %(message)s'
    log_handler.setFormatter(HubFormatter(log_format))
    log_handler.setLevel(logging.DEBUG)
    logger.addHandler(log_handler)


def setup_logging2(opts):
    global log_handler
    """Adjust logging based on configuration options"""
    # determine log level
    level = opts['LogLevel']
    valid_levels = ('DEBUG', 'INFO', 'WARNING', 'ERROR', 'CRITICAL')
    # the config value can be a single level name or a series of
    # logger:level names pairs. processed in order found
    default = None
    for part in level.split():
        pair = part.split(':', 1)
        if len(pair) == 2:
            name, level = pair
        else:
            name = 'koji'
            level = part
            default = level
        if level not in valid_levels:
            raise koji.GenericError("Invalid log level: %s" % level)
        # all our loggers start with koji
        if name == '':
            name = 'koji'
            default = level
        elif name.startswith('.'):
            name = 'koji' + name
        elif not name.startswith('koji'):
            name = 'koji.' + name
        level_code = logging.getLevelName(level)
        logging.getLogger(name).setLevel(level_code)
    logger = logging.getLogger("koji")
    # if KojiDebug is set, force main log level to DEBUG
    if opts.get('KojiDebug'):
        logger.setLevel(logging.DEBUG)
    elif default is None:
        # LogLevel did not configure a default level
        logger.setLevel(logging.WARNING)
    # log_handler defined in setup_logging1
    log_handler.setFormatter(HubFormatter(opts['LogFormat']))


def get_memory_usage():
    pagesize = resource.getpagesize()
    statm = [pagesize * int(y) // 1024
             for y in "".join(open("/proc/self/statm").readlines()).strip().split()]
    size, res, shr, text, lib, data, dirty = statm
    return res - shr


def server_setup(environ):
    global opts, plugins, registry, policy
    logger = logging.getLogger('koji')
    try:
        setup_logging1()
        opts = load_config(environ)
        setup_logging2(opts)
        koji.util.setup_rlimits(opts)
        plugins = load_plugins(opts)
        registry = get_registry(opts, plugins)
        policy = get_policy(opts, plugins)
        if opts.get('DBConnectionString'):
            db.provideDBopts(dsn=opts['DBConnectionString'])
        else:
            db.provideDBopts(database=opts["DBName"],
                             user=opts["DBUser"],
                             password=opts.get("DBPass", None),
                             host=opts.get("DBHost", None),
                             port=opts.get("DBPort", None))
    except Exception:
        tb_str = ''.join(traceback.format_exception(*sys.exc_info()))
        logger.error(tb_str)
        opts = {
            'ServerOffline': True,
            'OfflineMessage': 'server startup error',
        }


#
# wsgi handler
#

firstcall = True
firstcall_lock = threading.Lock()


def application(environ, start_response):
    global firstcall
    if firstcall:
        with firstcall_lock:
            # check again, another thread may be ahead of us
            if firstcall:
                server_setup(environ)
                firstcall = False
    # XMLRPC uses POST only. Reject anything else
    if environ['REQUEST_METHOD'] != 'POST':
        extra_headers = [
            ('Allow', 'POST'),
        ]
        response = "Method Not Allowed\n" \
                   "This is an XML-RPC server. Only POST requests are accepted.\n"
        return error_reply(start_response, '405 Method Not Allowed', response, extra_headers)
    if opts.get('ServerOffline'):
        return offline_reply(start_response, msg=opts.get("OfflineMessage", None))
    # XXX check request length
    # XXX most of this should be moved elsewhere
    if 1:
        try:
            start = time.time()
            memory_usage_at_start = get_memory_usage()

            context._threadclear()
            context.commit_pending = False
            context.opts = opts
            context.handlers = HandlerAccess(registry)
            context.environ = environ
            context.policy = policy
            try:
                context.cnx = db.connect()
            except Exception:
                return offline_reply(start_response, msg="database outage")
            h = ModXMLRPCRequestHandler(registry)
            try:
                if environ.get('CONTENT_TYPE') == 'application/octet-stream':
                    response = h._wrap_handler(h.handle_upload, environ)
                else:
                    response = h._wrap_handler(h.handle_rpc, environ)
            except BadRequest as e:
                return error_reply(start_response, '400 Bad Request', str(e) + '\n')
            except RequestTimeout as e:
                return error_reply(start_response, '408 Request Timeout', str(e) + '\n')
            response = response.encode()
            headers = GLOBAL_HEADERS + [
                ('Content-Length', str(len(response))),
                ('Content-Type', "text/xml"),
            ]
            start_response('200 OK', headers)
            if h.traceback:
                # rollback
                context.cnx.rollback()
            elif context.commit_pending:
                # Currently there is not much data we can provide to the
                # pre/postCommit callbacks. The handler can access context at
                # least
                koji.plugin.run_callbacks('preCommit')
                context.cnx.commit()
                koji.plugin.run_callbacks('postCommit')
            memory_usage_at_end = get_memory_usage()
            if memory_usage_at_end - memory_usage_at_start > opts['MemoryWarnThreshold']:
                paramstr = repr(getattr(context, 'params', 'UNKNOWN'))
                if len(paramstr) > 120:
                    paramstr = paramstr[:117] + "..."
                h.logger.warning(
                    "Memory usage of process %d grew from %d KiB to %d KiB (+%d KiB) processing "
                    "request %s with args %s" %
                    (os.getpid(), memory_usage_at_start, memory_usage_at_end,
                     memory_usage_at_end - memory_usage_at_start, context.method, paramstr))
            h.logger.debug("Returning %d bytes after %f seconds", len(response),
                           time.time() - start)
        finally:
            # make sure context gets cleaned up
            if hasattr(context, 'cnx'):
                try:
                    context.cnx.close()
                except Exception:
                    pass
            context._threadclear()
        return [response]  # XXX


def get_registry(opts, plugins):
    # Create and populate handler registry
    registry = HandlerRegistry()
    functions = kojihub.RootExports()
    hostFunctions = kojihub.HostExports()
    schedulerFunctions = scheduler.SchedulerExports()
    repoFunctions = repos.RepoExports()
    registry.register_instance(functions)
    registry.register_module(hostFunctions, "host")
    registry.register_module(schedulerFunctions, "scheduler")
    registry.register_module(repoFunctions, "repo")
    registry.register_function(auth.login)
    registry.register_function(auth.sslLogin)
    registry.register_function(auth.logout)
    registry.register_function(auth.subsession)
    registry.register_function(auth.logoutChild)
    registry.register_function(auth.exclusiveSession)
    registry.register_function(auth.sharedSession)
    for name in opts.get('Plugins', '').split():
        plugin = plugins.get(name)
        if not plugin:
            continue
        registry.register_plugin(plugin)
    return registry