= Requirements =
[[TracNav]]
* python 2.4 or later
* rrdTool
* MySQL
* other python modules:
      a) matplotlib

      b) pyrrdTool

      c) numpy

      d) pysnmp
      
      e) pysqlite

= Modules =

Currently, existing python scripts are:

* '''storeCons.py :''' this scrip has as a function to get the values of power consumption of the data center's machines in real-time via SNMP  (Simple Network Management Protocol) and to store them in the database . 
        NB: A cron job for this script is lunched every 5 minutes  

* '''getLoadFromRRD.py : ''' this is the python script for moving average load values from rrd databases to the PowerMon SQL database 
        NB: A cron job for this script is lunched every hour  

* ''' updateDb.py :''' update the database^1^ with the two configuration files: f_config_machines.cfg and f_config_pdus.cfg : 

     performs adding new pdu or a new machine to the database, and modifying their characteristics. 

     NB: The table 'PDU' must be modified before the table 'machine' because of foreign keys raisons

* ''' viewCons.py ''' The vizualisation script, that generates different plots via python plotting library `MatplotLib`,representing the power consumption and the average load of a machine during a certan period of time. This vizualisation tool is not finished yet 
{{{
1: PowerMon project supports all types of databases that are tolerated by sqlAlchemy (sqlite,mysql,posgresql,oracle...) 
     Therefore, we can specify which database we want to connect to , in the default section of f_config_pdus.cfg 
}}}
= Classes =

'''1. DbConn Objects: ''' A DbConn object is responsible of database connection management and all the interactions with it, DbConn class is 

implemented in module '''''dbConn.py'''''

Constructor: 

- **class** DbConn(dbName,dbType,username,password,host,port):
          `dbName,dbType,username,password,host,port` are string arguments specified in the configuration file : f_config_pdu.cfg on section //default//
           
          In PowerMon V1, "dbType" is either 'sqlite' or 'mysql' : other types may also be supported provided that they are supported by sqlAlchemy and that this constructor is appropriately modified 

All class methods: 

* `create_tables() :` Have to be called once, to create Powermon tables corresponding to the the following database schema : 
[[Image(https://trac.lal.in2p3.fr/PowerMon/browser/trunk/powermon_db_schema.png)]]

* `updatePDUtable(fConfigPDU):` Collects changes(add or modify existing pdu) from config file f_config_pdus.cfg and updates the table "PDU"

* `updateMachineTable(fConfigMachines):` Does the same job as `updatePDUtable()` for table "machine"

* `getIdOutlet(nomPDU,numOutlet):` Returns outlet ID of the outlet number `numOutlet`  belonging to pdu `nomPDU`

* `viewDb():` Prints the contents of tables : Outlet, machine and PDU

* `storeCons(nomMachine,cons,date):` Inserts a new line in the table powerCons  

* `viewTableMachine():` Display only the table : machine 

* `viewMachineCons(nomMachine):` Prints the power consumption values of the machine "nomMachine" whith the corresponding dates

* `getPDUs():` Returns a list of python dictionaries , representing the PDUs registred in the database 

* `getNomMachine(numOutlet,IdPDU):` Get the machine pluged-in on the outlet number "numOutlet" of the PDU whose Id is "IdPDU"

* `getMachines_Names():` Returns a list of all machines' names registred in the database 

* `getPduMachines(pduName):` Returns a set of machines' names correspondint to the connected machines to PDU "pduName"

* `getCons(nomMachine,start_date,end_date):` Returns a set of machine "nomMachine"'s  power consumption values from "start_date" to "end_date" and

    another set of the corresponding dates

* `getIdMachine(machineName):` Returns the Id of the machine named "machineName"

* `getLastLoadDate(IdMachine):` Returns the most recent date in table "cpu_charge" where the machine Id is "IdMachine"

* `storeLoad(IdMachine,dateList,avg1mn_list,avg5mn_list,avg15mn_list):` Inserts a new line to the table cpu_charge whith the given entry values

* `viewMachineLoad(nomMachine):` Prints the load values of the machine "nomMachine" whith the corresponding dates

'''2. PDU Objects: '''  A PDU object allows connexion to a supervisable pdu and extraction of machines' power consumption data , pdu class is 

implemented in module '''''pdu_snmp.py'''''

Constructor: 

- **class** PDU(nom,hostName,rootOID,nbOutlets,port,community,snmpVersion) :
            
            `nom,hostName,rootOID,nbOutlets,port,community,snmpVersion` are arguments collected from the table PDU , which can be modified by the file: //f_config_pdu.cfg// . 

All class methods: 

* `getData(no_outlet):` Performs asynchronous snmp Get and returns real time consumption value on outlet number "no_outlet"

* `getSetOfData():` Performs snmp walk and returns a set of real time consumption values on the PDU; and an integer representing the correponding timestamp.