update to new plugin API

2005/09/06 22:31:57-05:00 anl.gov!desai
Rename: src/lib/Server/Generators/TCheetah.py -> src/lib/Server/Plugins/TCheetah.py

(Logical change 1.300)


git-svn-id: https://svn.mcs.anl.gov/repos/bcfg/trunk/bcfg2@1224 ce84e21b-d406-0410-9b95-82705330c041

1 files changed, 110 insertions, 0 deletions

diff --git a/src/lib/Server/Plugins/TCheetah.py b/src/lib/Server/Plugins/TCheetah.py
index e69de29bb..528af2019 100644
--- a/src/lib/Server/Plugins/TCheetah.py
+++ b/src/lib/Server/Plugins/TCheetah.py
@@ -0,0 +1,110 @@
+'''This module implements a templating generator based on Cheetah'''
+__revision__ = '$Revision$'
+
+from posixpath import isdir
+from syslog import syslog, LOG_ERR
+from Bcfg2.Server.Plugin import Plugin, PluginExecutionError, FileBacked, SingleXMLFileBacked
+from elementtree.ElementTree import XML
+from xml.parsers.expat import ExpatError
+from Cheetah.Template import Template
+
+class TemplateFile(FileBacked):
+    '''Template file creates Cheetah template structures for the loaded file'''
+    def __init__(self, name, properties):
+        FileBacked.__init__(self, name)
+        self.properties = properties
+    
+    def Index(self):
+        '''Create the template data structures'''
+        self.template = Template(self.data, searchList=[self.properties])
+        self.template.properties = self.properties.properties
+        # put in owner permission detection
+
+    def BuildFile(self, entry, metadata):
+        '''Build literal file information'''
+        self.metadata = metadata
+        try:
+            entry.text = str(self.template)
+        except:
+            syslog(LOG_ERR, "TCheetah: Failed to template %s" % entry.get('name'))
+            raise PluginExecutionError
+        entry.attrib.update({'owner':'root', 'group':'root', 'perms':'0644'})
+
+
+class CheetahProperties(SingleXMLFileBacked):
+    '''Class for Cheetah properties'''
+    def Index(self):
+        '''Build data into an elementtree object for templating usage'''
+        try:
+            self.properties = XML(self.data)
+            del self.data
+        except ExpatError:
+            syslog(LOG_ERR, "TCheetah: Failed to parse properties")
+
+class TCheetah(Plugin):
+    '''The TCheetah generator implements a templating mechanism for configuration files'''
+    __name__ = 'TCheetah'
+    __version__ = '$Id$'
+    __author__ = 'bcfg-dev@mcs.anl.gov'
+
+    def __init__(self, core, datastore):
+        Plugin.__init__(self, core, datastore)
+        if self.data[-1] == '/':
+            self.data = self.data[:-1]
+        self.Entries['ConfigFile'] = {}
+        self.entries = {}
+        self.handles = {}
+        self.AddDirectoryMonitor('')
+        self.properties = CheetahProperties('%s/../etc/properties.xml' % self.data, self.core.fam)
+
+    def BuildEntry(self, entry, metadata):
+        '''Dispatch fetch calls to the correct object'''
+        self.entries[entry.get('name')].BuildFile(entry, metadata)
+
+    def MapName(self, name):
+        '''MapName finds the object corresponding to a particular file
+        the DirShadow MapName method maps filenames literally'''
+        return name        
+
+    def HandleEvent(self, event):
+        '''Unified FAM event handler for DirShadow'''
+        #print "got event %s %s %s" % ( event.code2str(), event.filename, event.requestID)
+        action = event.code2str()
+        if event.filename[0] == '/':
+            return
+        epath = "".join([self.data, self.handles[event.requestID], event.filename])
+        identifier = self.MapName(epath[len(self.data):])
+        if action in ['exists', 'created']:
+            if isdir(epath):
+                self.AddDirectoryMonitor(epath[len(self.data):])
+            else:
+                if self.entries.has_key(identifier):
+                    pass
+                else:
+                    #try:
+                    self.entries[identifier] = TemplateFile(epath, self.properties)
+                    self.entries[identifier].HandleEvent(event)
+                    self.Entries['ConfigFile'][identifier] = self.BuildEntry
+                    #except:
+                    #   syslog(LOG_ERR, "TCheetah: bad format for file %s" % identifier)
+        elif action == 'changed':
+            if self.entries.has_key(identifier):
+                self.entries[identifier].HandleEvent(event)
+        elif action == 'deleted':
+            if self.entries.has_key[identifier]:
+                del self.entries[identifier]
+                del self.Entries['ConfigFile'][identifier]
+                                 
+    def AddDirectoryMonitor(self, relative):
+        '''Add new directory to FAM structures'''
+        if not relative:
+            relative = '/'
+        if relative[-1] != '/':
+            relative += '/'
+        name = self.data + relative
+        if relative not in self.handles.values():
+            if not isdir(name):
+                print "Cheetah: Failed to open directory %s" % (name)
+                return
+            reqid = self.core.fam.AddMonitor(name, self)
+            self.handles[reqid] = relative