commit: 1dafdc7cdfc3254fa53c50c519d9f392fdfcb2cb
Author: Devan Franchini <twitch153 <AT> gentoo <DOT> org>
AuthorDate: Thu Jul 9 15:29:51 2015 +0000
Commit: Devan Franchini <twitch153 <AT> gentoo <DOT> org>
CommitDate: Thu Jul 9 15:29:51 2015 +0000
URL: https://gitweb.gentoo.org/proj/layman.git/commit/?id=1dafdc7c
xml.py: Adds XML database handler module
layman/db_modules/__init__.py | 0
layman/db_modules/xml/__init__.py | 24 ++++++
layman/db_modules/xml/xml.py | 175 ++++++++++++++++++++++++++++++++++++++
3 files changed, 199 insertions(+)
diff --git a/layman/db_modules/__init__.py b/layman/db_modules/__init__.py
new file mode 100644
index 0000000..e69de29
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 <twitch...@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)
