remove most of the resolver boilerplate, keep the interesting functions
Signed-off-by: Nico Schottelius <nico@brief.schottelius.org>
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					 1 changed files with 17 additions and 104 deletions
				
			
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					@ -213,78 +213,6 @@ class CdistObject(object):
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    def satisfied_requirements(self):
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					    def satisfied_requirements(self):
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# -*- coding: utf-8 -*-
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#
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# 2011 Steven Armstrong (steven-cdist at armstrong.cc)
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#
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# This file is part of cdist.
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#
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# cdist is free software: you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# the Free Software Foundation, either version 3 of the License, or
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# (at your option) any later version.
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#
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# cdist is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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# GNU General Public License for more details.
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#
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# You should have received a copy of the GNU General Public License
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# along with cdist. If not, see <http://www.gnu.org/licenses/>.
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#
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#
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import logging
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import os
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import itertools
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import fnmatch
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import cdist
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log = logging.getLogger(__name__)
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class CircularReferenceError(cdist.Error):
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    def __init__(self, cdist_object, required_object):
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        self.cdist_object = cdist_object
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        self.required_object = required_object
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    def __str__(self):
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        return 'Circular reference detected: %s -> %s' % (self.cdist_object.name, self.required_object.name)
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class RequirementNotFoundError(cdist.Error):
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    def __init__(self, requirement):
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        self.requirement = requirement
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    def __str__(self):
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        return 'Requirement could not be found: %s' % self.requirement
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class DependencyResolver(object):
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    """Cdist's dependency resolver.
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    Usage:
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    >> resolver = DependencyResolver(list_of_objects)
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    # Easy access to the objects we are working with
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    >> resolver.objects['__some_type/object_id']
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    <CdistObject __some_type/object_id>
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    # Easy access to a specific objects dependencies
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    >> resolver.dependencies['__some_type/object_id']
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    [<CdistObject __other_type/dependency>, <CdistObject __some_type/object_id>]
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    # Pretty print the dependency graph
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    >> from pprint import pprint
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    >> pprint(resolver.dependencies)
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    # Iterate over all existing objects in the correct order
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    >> for cdist_object in resolver:
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    >>     do_something_with(cdist_object)
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    """
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    def __init__(self, objects, logger=None):
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        self.objects = dict((o.name, o) for o in objects)
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        self._dependencies = None
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        self.log = logger or log
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    @property
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					    @property
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    def dependencies(self):
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					    def dependencies(self):
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        """Build the dependency graph.
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					        """Build the dependency graph.
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					@ -348,37 +276,22 @@ class DependencyResolver(object):
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                # preprocessed again if someone would call us multiple times.
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					                # preprocessed again if someone would call us multiple times.
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                cdist_object.autorequire = []
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					                cdist_object.autorequire = []
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    def _resolve_object_dependencies(self, cdist_object, resolved, unresolved):
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        """Resolve all dependencies for the given cdist_object and store them
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        in the list which is passed as the 'resolved' arguments.
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        e.g.
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					class CircularReferenceError(cdist.Error):
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        resolved = []
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					    def __init__(self, cdist_object, required_object):
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        unresolved = []
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					        self.cdist_object = cdist_object
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        resolve_object_dependencies(some_object, resolved, unresolved)
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					        self.required_object = required_object
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        print("Dependencies for %s: %s" % (some_object, resolved))
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        """
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					    def __str__(self):
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        self.log.debug('Resolving dependencies for: %s' % cdist_object.name)
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					        return 'Circular reference detected: %s -> %s' % (self.cdist_object.name, self.required_object.name)
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        try:
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            unresolved.append(cdist_object)
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            for required_object in self.find_requirements_by_name(cdist_object.requirements):
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					class RequirementNotFoundError(cdist.Error):
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                self.log.debug("Object %s requires %s", cdist_object, required_object)
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					    def __init__(self, requirement):
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                if required_object not in resolved:
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					        self.requirement = requirement
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                    if required_object in unresolved:
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                        raise CircularReferenceError(cdist_object, required_object)
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					    def __str__(self):
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                    self._resolve_object_dependencies(required_object, resolved, unresolved)
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					        return 'Requirement could not be found: %s' % self.requirement
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            resolved.append(cdist_object)
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            unresolved.remove(cdist_object)
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        except RequirementNotFoundError as e:
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            raise cdist.CdistObjectError(cdist_object, "requires non-existing " + e.requirement)
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    def __iter__(self):
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        """Iterate over all unique objects and yield them in the correct order.
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        """
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        iterable = itertools.chain(*self.dependencies.values())
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        # Keep record of objects that have already been seen
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        seen = set()
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        seen_add = seen.add
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        for cdist_object in itertools.filterfalse(seen.__contains__, iterable):
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            seen_add(cdist_object)
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            yield cdist_object
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