(Logical change 1.186)

git-svn-id: https://svn.mcs.anl.gov/repos/bcfg/trunk/bcfg2@793 ce84e21b-d406-0410-9b95-82705330c041

1 files changed, 103 insertions, 0 deletions

diff --git a/src/lib/Server/Statistics.py b/src/lib/Server/Statistics.py
index e69de29bb..10223acfb 100644
--- a/src/lib/Server/Statistics.py
+++ b/src/lib/Server/Statistics.py
@@ -0,0 +1,103 @@
+'''This file manages the statistics collected by the BCFG2 Server'''
+__revision__ = '$Revision: $'
+
+from elementtree.ElementTree import XML, SubElement, Element
+from xml.parsers.expat import ExpatError
+from syslog import syslog, LOG_INFO, LOG_ERR
+from time import asctime, localtime, time
+
+class Statistics(object):
+    '''Manages the memory and file copy of statistics collected about client runs'''
+    __min_write_delay__ = 30
+
+    def __init__(self, filename):
+        self.filename = filename
+        self.element = Element('Dummy')
+        self.dirty = 0
+        self.lastwrite = 0
+        self.ReadFromFile()
+
+    def pretty_print(self, element, level=0):
+        '''Produce a pretty-printed text representation of element'''
+        if element.text:
+            fmt = "%s<%%s %%s>%%s</%%s>" % (level*" ")
+            data = (element.tag, (" ".join(["%s='%s'" % x for x in element.attrib.iteritems()])),
+                    element.text, element.tag)
+        if element._children:
+            fmt = "%s<%%s %%s>\n" % (level*" ",) + (len(element._children) * "%s") + "%s</%%s>\n" % (level*" ")
+            data = (element.tag, ) + (" ".join(["%s='%s'" % x for x in element.attrib.iteritems()]),)
+            data += tuple([self.pretty_print(x, level+2) for x in element._children]) + (element.tag, )
+        else:
+            fmt = "%s<%%s %%s/>\n" % (level * " ")
+            data = (element.tag, " ".join(["%s='%s'" % x for x in element.attrib.iteritems()]))
+        return fmt % data
+
+    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")
+            fout = open(self.filename, 'w')
+            fout.write(self.pretty_print(self.element))
+            fout.close()
+            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, ExpatError):
+            syslog(LOG_ERR, "Statistics: Failed to parse %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 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]
+        nl = len(nodes)
+        if nl == 0:
+            # Create an entry for this node
+            node = SubElement(self.element, 'Node', name=client)
+        elif nl == 1 and not node_dirty:
+            # Delete old instance
+            self.element.remove(nodes[0])
+            node = SubElement(self.element, 'Node', name=client)
+        elif nl == 1 and node_dirty:
+            # Delete old dirty statistics entry
+            node = nodes[0]
+            for elem in [elem for elem in node.findall('Statistics') if elem.get('state') == 'dirty']:
+                node.remove(elem)
+        else:
+            # Shouldn't be reached
+            syslog(LOG_ERR, "Statistics: 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