PCP<->CIM bridge prototype v3

- contents properly built/packaged into openlmi-pcp subrpm
- a cron.daily job conditionally (rarely) rebuilds the MOF/REG files
  based upon current PCP state
- /usr/bin/openlmi-pcp-generate able to be run by hand, cron.daily job minimal
- more run-time PCP error tolerance

6 files changed, 334 insertions, 0 deletions

diff --git a/src/pcp/README b/src/pcp/README
new file mode 100644
index 0000000..1f5e225
--- /dev/null
+++ b/src/pcp/README
@@ -0,0 +1,52 @@
+CIM <-> PCP (http://oss.sgi.com/projects/pcp) bridge
+<fche@redhat.com>
+
+The idea of the bridge is to create a suite of CIM classes (derived from
+CIM_StatisticsData), each of which represents one PCP metric.  There are
+hundreds of these.  (Since PCP metrics can come and go, the MOF and REG
+files may be regenerated by a simple shell script at any with an enclosed
+shell script.)
+
+Install PCP and start the pmcd service to start.  We assume you're
+already running OpenLMI / Pegasus with a client like YAWN and are far
+more familiar with this WBEM business than the author.  Install the
+CIM <-> PCP bridge thusly:
+
+        vi PCP_pmns2mofreg.sh # to fix the path to pcp-metric.py 
+        sh PCP_pmns2mofreg.sh mof > PCP_Metric_PMNS.mof
+        sh PCP_pmns2mofreg.sh reg > PCP_Metric_PMNS.reg
+        openlmi-mof-register register *.mof *.reg
+
+For example, whereas PCP command line tools may show these sorts of results:
+
+        % pminfo -dTf hinv.machine
+
+        hinv.machine
+            Data Type: string  InDom: PM_INDOM_NULL 0xffffffff
+            Semantics: discrete  Units: none
+        Help:
+        machine name, IP35 if SGI SNIA, else simply linux
+            value "linux"
+
+        % pminfo -dTf network.interface.total.bytes
+        network.interface.total.bytes
+            Data Type: 64-bit unsigned int  InDom: 60.3 0xf000003
+            Semantics: counter  Units: byte
+        Help:
+        network total (in+out) bytes from /proc/net/dev per network interface
+            inst [0 or "eth0"] value 585236365
+            inst [1 or "lo"] value 85894766
+
+These same metrics would show up in the CIM namespace as classes
+
+        PCP_Metric_hinv__machine
+and     PCP_Metric_network__interface__total__bytes
+
+with instances with InstanceIDs such as
+
+        PCP:hinv.machine
+        PCP:network.interface.total.bytes:lo
+        PCP:network.interface.total.bytes:eth0
+
+These currently supply a string-formatted value of the respective
+metric measurement, an accurate StatisticTime, and other metadata.
diff --git a/src/pcp/lmi/pcp/__init__.py b/src/pcp/lmi/pcp/__init__.py
new file mode 100644
index 0000000..81de2e5
--- /dev/null
+++ b/src/pcp/lmi/pcp/__init__.py
@@ -0,0 +1,25 @@
+# PCP bridge Providers
+#
+# Copyright (C) 2013 Red Hat, Inc.  All rights reserved.
+#
+# This library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2.1 of the License, or (at your option) any later version.
+#
+# This library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this library; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+#
+# Authors: Frank Ch. Eigler <fche@redhat.com>
+#
+
+"""
+CIM providers for PCP metrics.
+Part of OpenLMI project.
+"""
diff --git a/src/pcp/lmi/pcp/metric.py b/src/pcp/lmi/pcp/metric.py
new file mode 100644
index 0000000..454f54a
--- /dev/null
+++ b/src/pcp/lmi/pcp/metric.py
@@ -0,0 +1,167 @@
+"""Python Provider for PCP_Metric_*
+Instruments the CIM class family PCP_Metric_*
+"""
+
+from pywbem.cim_provider2 import CIMProvider2
+import pywbem
+from pcp import pmapi
+import cpmapi as c_api
+import datetime
+
+context = None  # persistent pcp context
+
+
+# Since we serve a whole slew of PCP_Metric_** subclasses, we can't
+# use a straight classname->provider-class dictionary.
+#
+#def get_providers(env): 
+#    return {'PCP_Metric_****': PCP_MetricProvider} 
+#
+# Instead, we implement the one-hop-higher proxy-level function calls,
+# namely the IM_* functions at the bottom.
+
+
+# Undo mangling done by PCP_pmns2mofreg.sh
+def MOFname_to_PCPmetric (op):
+    assert (op.namespace == 'root/cimv2')
+    assert (op.classname[0:11] == 'PCP_Metric_')
+    return op.classname[11:].replace('__', '.')
+
+
+# Search the given PM_ResultSet for a given instance number (if any);
+# return formatted CIM of the value (or CIM None)
+def PCP_CIMValueString (context, result, desc, inst):
+    for i in range (0,result.contents.get_numval(0)):
+        value = result.contents.get_vlist(0,i)
+        iv = value.inst
+        if (inst is not None and inst != iv):
+            continue
+        atom = context.pmExtractValue (result.contents.get_valfmt(0),
+                                       value,
+                                       desc.contents.type,
+                                       desc.contents.type)
+        atomValue = atom.dref(desc.contents.type) # nb: atomValue could be numeric etc.
+        return pywbem.CIMProperty(name='ValueString',
+                                  value=str(atomValue), # stringify it here
+                                  type='string')
+
+    return pywbem.CIMProperty(name='ValueString',
+                              value=None,
+                              type='string')
+
+
+def PCP_CIMStatisticTime (result):
+    dt = datetime.datetime.fromtimestamp(float(str(result.contents.timestamp)))
+    return pywbem.CIMDateTime(dt)
+
+
+# generic payload generator, used for
+# - iterating across instance domains (keys_only=1)
+# - fetching metric values
+# - fetching metric metadata (for those model/filter fields set)
+def get_instance (env, op, model, keys_only):
+    metric = MOFname_to_PCPmetric (op)
+    global context
+
+    try:
+        if (context == None):
+            context = pmapi.pmContext() # localhost or equivalent
+        context.pmReconnectContext() # in case it was nuked recently
+    except pmapi.pmErr, e:
+        context = None
+        raise pywbem.CIMError(pywbem.CIM_ERR_FAILED, "Unable to connect to local PMCD:" + str(e))
+        
+    pmids = context.pmLookupName(metric)
+    pmid = pmids[0]
+    desc = context.pmLookupDesc(pmid)
+
+    if ('InstanceID' in model):
+        selected_instanceid = model['InstanceID']
+    else:
+        selected_instanceid = None
+    
+    model.path.update({'InstanceID':None})
+
+    if (not keys_only):
+        model['PMID'] = pywbem.Uint32(pmid)
+        model['ElementName'] = metric
+        # must not fail, or else we have no metric value data worth sharing
+        try:
+            results = context.pmFetch(pmids)
+        except pmapi.pmErr, e:
+            # fatal
+            raise pywbem.CIMError(pywbem.CIM_ERR_FAILED, "PCP pmFetch failed:" + str(e))
+        # cannot fail
+        model['Units'] = context.pmUnitsStr(desc.contents.units)
+        model['Type'] = context.pmTypeStr(desc.contents.type)
+        # these may fail, but not fatally
+        try:
+            model['Caption'] = context.pmLookupText(pmid)
+        except pmapi.pmErr:
+            pass
+        try:
+            model['Description'] = context.pmLookupText(pmid, c_api.PM_TEXT_HELP)
+        except pmapi.pmErr:
+            pass
+
+    try:
+        instL, nameL = context.pmGetInDom(desc)
+        for iL, nL in zip(instL, nameL):
+            new_instanceid = 'PCP:'+metric+':'+nL
+            if (selected_instanceid is None or
+                new_instanceid == selected_instanceid):
+                model['InstanceNumber'] = pywbem.Uint32(iL)
+                model['InstanceName'] = nL
+                model['InstanceID'] = new_instanceid
+                if (not keys_only):
+                    model['StatisticTime'] = PCP_CIMStatisticTime (results)
+                    model['ValueString'] = PCP_CIMValueString (context, results, desc, iL)
+                yield model
+    except pmapi.pmErr: # pmGetInDom is expected to fail for non-instance (PM_INDOM_NULL) metrics 
+        new_instanceid = 'PCP:'+metric
+        if (selected_instanceid is None or
+            new_instanceid == selected_instanceid):
+            model['InstanceNumber'] = pywbem.CIMProperty(name='InstanceNumber',
+                                                         value=None,type='uint32')
+            model['InstanceName'] = pywbem.CIMProperty(name='InstanceName',
+                                                       value=None,type='string')
+            model['InstanceID'] = new_instanceid
+            if (not keys_only):
+                model['StatisticTime'] = PCP_CIMStatisticTime (results)
+                model['ValueString'] = PCP_CIMValueString (context, results, desc, None)
+            yield model
+        
+# hooks for impersonating CIMProvider2 functions
+
+    
+def MI_enumInstanceNames (env, op):
+    model = pywbem.CIMInstance(classname = op.classname, path=op)
+    for x in get_instance (env, op, model, True):
+        yield x.path
+
+def MI_enumInstances (env, op, plist):
+    model = pywbem.CIMInstance(classname = op.classname, path=op)
+    return get_instance (env, op, model, False)
+
+def MI_getInstance (env, op, plist):
+    proplist = None
+    if plist is not None:
+        proplist = [s.lower() for s in propertyList]
+        proplist+= [s.lower() for s in op.keybindings.keys()]
+    model = pywbem.CIMInstance(classname=op.classname, path=op,
+                               property_list=proplist)
+    model.update(model.path.keybindings)
+    for x in get_instance (env, op, model, False):
+        return x # XXX: first one
+
+def MI_createInstance (env, pinst):
+    raise pywbem.CIMError(pywbem.CIM_ERR_NOT_SUPPORTED)
+
+def MI_modifyInstance (env, pinst, plist):
+    raise pywbem.CIMError(pywbem.CIM_ERR_NOT_SUPPORTED)
+
+def MI_deleteInstance (env, piname):
+    raise pywbem.CIMError(pywbem.CIM_ERR_NOT_SUPPORTED)
+
+# See also extra MI_* functions for associations, etc.;
+# cmpi-bindings.git swig/python/cmpi_pywbem_bindings.py
diff --git a/src/pcp/openlmi-pcp-generate b/src/pcp/openlmi-pcp-generate
new file mode 100644
index 0000000..8c53512
--- /dev/null
+++ b/src/pcp/openlmi-pcp-generate
@@ -0,0 +1,68 @@
+#! /bin/sh
+
+# This script refreshes WBEM/CIM MOF & REG files from the current PCP PMNS,
+# if necessary, and reloads the new MOF/REGs into the CIMMON.
+#
+# The PCP PMNS changes infrequently (when the sysadmin manuall installs or
+# removes pcp PMDA (agent) modules in /var/lib/pcp/pmdas/*).
+#
+# This script encodes the PCP->CIM metric name-mapping convention of replacing
+# dots with double-underscores, which lmi/pcp/metric.py will dutifully undo.
+
+_LOCALSTATEDIR=/var
+_DATADIR=/usr/share
+NAME=openlmi-providers
+PYTHON2_SITELIB=/usr/lib/python2.7/site-packages
+
+PCP_PMNS=$_LOCALSTATEDIR/lib/pcp/pmns/root
+PCP_HOST=${1-localhost} # or local:// for pcp 3.9+
+BASEMOFFILE=$_DATADIR/$NAME/60_LMI_PCP.mof
+MOFREGDIR=$_LOCALSTATEDIR/lib/$NAME
+STAMPFILE=$MOFREGDIR/stamp
+MOFFILE=$MOFREGDIR/60_LMI_PCP_PMNS.mof
+REGFILE=$MOFREGDIR/60_LMI_PCP_PMNS.reg
+PROVIDER=$PYTHON2_SITELIB/lmi/pcp/metric.py
+
+if [ ! -f $PROVIDER ]; then
+    echo "Cannot find $PROVIDER" 1>&2
+    exit 1
+fi
+
+set -e
+
+echo Refreshing PCP_Metric CIMMON classes from current PCP PMNS
+
+# quick liveness test
+pcp -h $PCP_HOST
+
+if [ -s $PCP_PMNS -a $PCP_PMNS -nt $STAMPFILE ]; then
+    if [ -f $MOFFILE -a -f $REGFILE ]; then
+        echo Unregistering $BASEMOFFILE
+        echo Unregistering previous $MOFFILE
+        echo Unregistering previous $REGFILE
+        openlmi-mof-register unregister $BASEMOFFILE $MOFFILE $REGFILE || :
+    fi
+
+    echo Generating $MOFFILE
+    pminfo -h $PCP_HOST | sed -e 's,\.,__,g'  | 
+    awk '{print "class PCP_Metric_" $1 " : PCP_MetricValue { } ;" }' > $MOFFILE
+
+    echo Generating $REGFILE
+    pminfo -h $PCP_HOST | sed -e 's,\.,__,g'  |
+    awk '{print "[PCP_Metric_" $1 "]"
+         print "  provider: '$PROVIDER'"
+         print "  location: pyCmpiProvider"
+         print "  type: instance"
+         print "  namespace: root/cimv2"
+         print "  group: pcp"
+         print ""}' > $REGFILE
+
+    echo Registering $BASEMOFFILE
+    echo Registering new $MOFFILE
+    echo Registering new $REGFILE
+    openlmi-mof-register register $BASEMOFFILE $MOFFILE $REGFILE 2>&1 | # filter out two noise diagnostics
+    egrep -v 'Warning: the instance already exists.|In this implementation, that means it cannot be changed.' || :
+    touch $STAMPFILE
+else
+    echo Doing nothing, $PCP_PMNS older than $STAMPFILE
+fi
diff --git a/src/pcp/openlmi-pcp.cron b/src/pcp/openlmi-pcp.cron
new file mode 100644
index 0000000..a9691f0
--- /dev/null
+++ b/src/pcp/openlmi-pcp.cron
@@ -0,0 +1,3 @@
+#! /bin/sh
+
+openlmi-pcp-generate localhost >/dev/null 2>&1
diff --git a/src/pcp/setup.py b/src/pcp/setup.py
new file mode 100644
index 0000000..9ffa320
--- /dev/null
+++ b/src/pcp/setup.py
@@ -0,0 +1,19 @@
+from setuptools import setup
+setup(
+    name='lmi-pcp',
+    description='PCP metric providers',
+    author='Frank Ch. Eigler',
+    author_email='fche@redhat.com',
+    url='https://fedorahosted.org/openlmi/',
+    version='0.1',
+    namespace_packages=['lmi'],
+    packages=[
+        'lmi.pcp'],
+    install_requires=['lmi', 'pcp'],
+    license="LGPLv2+",
+    classifiers=[
+        'License :: OSI Approved :: GNU Lesser General Public License v2 or later (LGPLv2+)',
+        'Operating System :: POSIX :: Linux',
+        'Topic :: System :: Systems Administration',
+        ]
+    )