move xml statistics over to new typed-plugin system (enables direct-to-django statistics plugin)

git-svn-id: https://svn.mcs.anl.gov/repos/bcfg/trunk/bcfg2@4817 ce84e21b-d406-0410-9b95-82705330c041

1 files changed, 120 insertions, 0 deletions

diff --git a/src/lib/Server/Plugins/Statistics.py b/src/lib/Server/Plugins/Statistics.py
new file mode 100644
index 000000000..bc6e648bf
--- /dev/null
+++ b/src/lib/Server/Plugins/Statistics.py
@@ -0,0 +1,120 @@
+'''This file manages the statistics collected by the BCFG2 Server'''
+__revision__ = '$Revision$'
+
+from lxml.etree import XML, SubElement, Element, XMLSyntaxError
+from time import asctime, localtime, time, strptime, mktime
+
+import logging, lxml.etree, os
+
+import Bcfg2.Server.Plugin
+
+class StatisticsStore(object):
+    '''Manages the memory and file copy of statistics collected about client runs'''
+    __min_write_delay__ = 0
+
+    def __init__(self, filename):
+        self.filename = filename
+        self.element = Element('Dummy')
+        self.dirty = 0
+        self.lastwrite = 0
+        self.logger = logging.getLogger('Bcfg2.Server.Statistics')
+        self.ReadFromFile()
+
+    def WriteBack(self, force=0):
+        '''Write statistics changes back to persistent store'''
+        if (self.dirty and (self.lastwrite + self.__min_write_delay__ <= time()) ) \
+                or force:
+            #syslog(LOG_INFO, "Statistics: Updated statistics.xml")
+            try:
+                fout = open(self.filename + '.new', 'w')
+            except IOError, ioerr:
+                self.logger.error("Failed to open %s for writing: %s" % (self.filename + '.new', ioerr))
+            else:
+                fout.write(lxml.etree.tostring(self.element, encoding='UTF-8', xml_declaration=True))
+                fout.close()
+                os.rename(self.filename + '.new', self.filename)
+                self.dirty = 0
+                self.lastwrite = time()
+
+    def ReadFromFile(self):
+        '''Reads current state regarding statistics'''
+        try:
+            fin = open(self.filename, 'r')
+            data = fin.read()
+            fin.close()
+            self.element = XML(data)
+            self.dirty = 0
+            #syslog(LOG_INFO, "Statistics: Read in statistics.xml")
+        except (IOError, XMLSyntaxError):
+            self.logger.error("Creating new statistics file %s"%(self.filename))
+            self.element = Element('ConfigStatistics')
+            self.WriteBack()
+            self.dirty = 0
+
+    def updateStats(self, xml, client):
+        '''Updates the statistics of a current node with new data'''
+
+        # Current policy: 
+        # - Keep anything less than 24 hours old
+        #   - Keep latest clean run for clean nodes
+        #   - Keep latest clean and dirty run for dirty nodes
+        newstat =  xml.find('Statistics')
+
+        if newstat.get('state') == 'clean':
+            node_dirty = 0
+        else:
+            node_dirty = 1
+
+        # Find correct node entry in stats data
+        # The following list comprehension should be guarenteed to return at
+        # most one result
+        nodes = [elem for elem in self.element.findall('Node') if elem.get('name') == client]
+        nummatch = len(nodes)
+        if nummatch == 0:
+            # Create an entry for this node
+            node = SubElement(self.element, 'Node', name=client)
+        elif nummatch == 1 and not node_dirty:
+            # Delete old instance
+            node = nodes[0]
+            [node.remove(elem) for elem in node.findall('Statistics') if self.isOlderThan24h(elem.get('time'))]
+        elif nummatch == 1 and node_dirty:
+            # Delete old dirty statistics entry
+            node = nodes[0]
+            [node.remove(elem) for elem in node.findall('Statistics') if (elem.get('state') == 'dirty' and self.isOlderThan24h(elem.get('time')))]
+        else:
+            # Shouldn't be reached
+            self.logger.error("Duplicate node entry for %s"%(client))
+
+        # Set current time for stats
+        newstat.set('time', asctime(localtime()))
+
+        # Add statistic
+        node.append(newstat)
+
+        # Set dirty
+        self.dirty = 1
+        self.WriteBack()
+
+
+    def isOlderThan24h(self, testTime):
+        '''Helper function to determine if <time> string is older than 24 hours'''
+        now = time()
+        utime = mktime(strptime(testTime))
+        secondsPerDay = 60*60*24
+
+        return (now-utime) > secondsPerDay
+
+class Statistics(Bcfg2.Server.Plugin.StatisticsPlugin):
+    __name__ = 'Statistics'
+    __version__ = '$Id$'
+
+    def __init__(self, _, datastore):
+        fpath = "%s/etc/statistics.xml" % datastore
+        self.data = StatisticsStore(fpath)
+
+    def StoreStatistics(self, client, xdata):
+        self.data.updateStats(xdata, client.hostname)
+
+    def WriteBack(self):
+        self.data.WriteBack()
+