diff options
| -rw-r--r-- | layman/db_modules/__init__.py | 0 | ||||
| -rw-r--r-- | layman/db_modules/xml/__init__.py | 24 | ||||
| -rw-r--r-- | layman/db_modules/xml/xml.py | 175 |
3 files changed, 199 insertions, 0 deletions
diff --git a/layman/db_modules/__init__.py b/layman/db_modules/__init__.py new file mode 100644 index 0000000..e69de29 --- /dev/null +++ b/layman/db_modules/__init__.py diff --git a/layman/db_modules/xml/__init__.py b/layman/db_modules/xml/__init__.py new file mode 100644 index 0000000..96861d7 --- /dev/null +++ b/layman/db_modules/xml/__init__.py @@ -0,0 +1,24 @@ +# Copyright 2015 Gentoo Foundation +# Distributed under the terms of the GNU General Public License v2 + +''' +XML database plug-in module for layman. +''' + +module_spec = { + 'name': 'xml', + 'description': __doc__, + 'provides':{ + 'xml-module': { + 'name': 'xml', + 'class': 'DBHandler', + 'description': __doc__, + 'functions': ['add_new', 'read_db', 'write'], + 'func_desc': { + 'add_new': 'Adds new overlay(s) to database', + 'read_db': 'Reads the list of registered overlays from config', + 'write' : 'Writes the list of registered overlay to config', + }, + } + } +} diff --git a/layman/db_modules/xml/xml.py b/layman/db_modules/xml/xml.py new file mode 100644 index 0000000..189e868 --- /dev/null +++ b/layman/db_modules/xml/xml.py @@ -0,0 +1,175 @@ +#!/usr/bin/python +# -*- coding: utf-8 -*- +################################################################################# +# LAYMAN XML DB +################################################################################# +# File: xml.py +# +# Access XML overlay database(s). +# +# Copyright: +# (c) 2015 Devan Franchini +# Distributed under the terms of the GNU General Public License v2 +# +# Author(s): +# Devan Franchini <twitch153@gentoo.org> +# +'''Handler for xml overlay databases.''' + +from __future__ import unicode_literals + +__version__ = "$Id: xml.py 273 2015-07-07 10:30:30Z twitch153 $" + +#=============================================================================== +# +# Dependencies +# +#------------------------------------------------------------------------------- + +import sys +import xml +import xml.etree.ElementTree as ET # Python 2.5 + +from layman.utils import indent +from layman.compatibility import fileopen +from layman.overlays.overlay import Overlay + + +#py3.2+ +if sys.hexversion >= 0x30200f0: + _UNICODE = 'unicode' +else: + _UNICODE = 'UTF-8' + + +#=============================================================================== +# +# Class BrokenOverlayCatalog +# +#------------------------------------------------------------------------------- + +class BrokenOverlayCatalog(ValueError): + def __init__(self, origin, expat_error, hint=None): + if hint == None: + hint = '' + else: + hint = '\nHint: %s' % hint + + super(BrokenOverlayCatalog, self).__init__( + 'XML parsing failed for "%(origin)s" (line %(line)d, column'\ + '%(column)d)%(hint)s' % {'line': expat_error.lineno, + 'column':expat_error.offset + 1, + 'origin':origin, 'hint':hint}) + + +#=============================================================================== +# +# Class DbBase +# +#------------------------------------------------------------------------------- + +class DBHandler(object): + ''' + Handle a xml overlay database. + ''' + + def __init__(self, config, overlays, paths=None, ignore=0, + ignore_init_read_errors=False): + + self.config = config + self.ignore = ignore + self.overlays = overlays + self.paths = paths + self.output = config['output'] + self.ignore_init_read_errors = ignore_init_read_errors + + self.output.debug('Initializing XML overlay list handler', 8) + + + def __eq__(self, other): + for key in set(self.overlays.keys()) | set(other.overlays.keys()): + if self.overlays[key] != other.overlays[key]: + return False + return True + + + def __ne__(self, other): + return not self.__eq__(other) + + + def _broken_catalog_hint(self): + this_function_name = sys._getframe().f_code.co_name + + msg = 'Method "%(name)s.%(func)s" not implemented'\ + % {'name': self.__class__.__name__, + 'func': this_function_name} + + raise NotImplementedError(msg) + + + def read_db(self, path): + ''' + Read the overlay definition file. + ''' + try: + with fileopen(path, 'r') as df: + document = df.read() + except Exception as error: + if not self.ignore_init_read_errors: + msg = 'XML DBHandler - Failed to read the overlay list at'\ + '("%(path)s")' % {'path': path} + self.output.error(msg) + raise error + + self.read(document, origin=path) + + + def read(self, text, origin): + ''' + Read an xml list of overlays (adding to and potentially overwriting + existing entries) + ''' + try: + document = ET.fromstring(text) + except xml.parsers.expat.ExpatError as err: + raise BrokenOverlayCatalog(origin, err, self._broken_catalog_hint()) + + overlays = document.findall('overlay') + document.findall('repo') + + for overlay in overlays: + msg = 'XML DBHandler - Parsing overlay: %(ovl)s' % {'ovl': overlay} + self.output.debug(msg, 9) + ovl = Overlay(config=self.config, xml=overlay, ignore=self.ignore) + self.overlays[ovl.name] = ovl + + + def add_new(self, xml=None, origin=None): + ''' + Reads xml text and dictionary definitions and adds + them to the db. + ''' + if not xml: + msg = 'XML DBHandler - add_new() failed: XML text cannot be none' + self.output.warn(msg) + return False + + self.read(xml, origin) + return True + + + def write(self, path): + ''' + Write the list of overlays to a file. + ''' + tree = ET.Element('repositories', version="1.0", encoding=_UNICODE) + tree[:] = [e.to_xml() for e in self.overlays.values()] + indent(tree) + tree = ET.ElementTree(tree) + try: + with fileopen(path, 'w') as f: + tree.write(f, encoding=_UNICODE) + + except Exception as err: + msg = 'Failed to write to local overlays file: %(path)s\nError was'\ + ':\n%(err)s' % {'path': path, 'err': err} + raise Exception(msg) |