#encoding:utf-8
#name:mod_db.py
'''''
使用方法：1.在主程序中先實例化DB Mysql數(shù)據(jù)庫操作類。
   2.使用方法:db=database() db.fetch_all("sql")
'''
import MySQLdb
import MySQLdb.cursors
import mod_config
import mod_logger
DB = "database"
LOGPATH = mod_config.getConfig('path', 'logpath') + 'database.log'
DBNAME = mod_config.getConfig(DB, 'dbname')
DBHOST = mod_config.getConfig(DB, 'dbhost')
DBUSER = mod_config.getConfig(DB, 'dbuser')
DBPWD = mod_config.getConfig(DB, 'dbpassword')
DBCHARSET = mod_config.getConfig(DB, 'dbcharset')
DBPORT = mod_config.getConfig(DB, "dbport")
logger = mod_logger.logger(LOGPATH)
#數(shù)據(jù)庫操作類
class database:
#注，python的self等于其它語言的this
  def __init__(self, dbname=None, dbhost=None):
    self._logger = logger
    #這里的None相當(dāng)于其它語言的NULL
    if dbname is None:
      self._dbname = DBNAME
    else:
      self._dbname = dbname
    if dbhost is None:
      self._dbhost = DBHOST
    else:
      self._dbhost = dbhost
    self._dbuser = DBUSER
    self._dbpassword = DBPWD
    self._dbcharset = DBCHARSET
    self._dbport = int(DBPORT)
    self._conn = self.connectMySQL()
    if(self._conn):
      self._cursor = self._conn.cursor()
  #數(shù)據(jù)庫連接
  def connectMySQL(self):
    conn = False
    try:
      conn = MySQLdb.connect(host=self._dbhost,
          user=self._dbuser,
          passwd=self._dbpassword,
          db=self._dbname,
          port=self._dbport,
          cursorclass=MySQLdb.cursors.DictCursor,
          charset=self._dbcharset,
          )
    except Exception,data:
      self._logger.error("connect database failed, %s" % data)
      conn = False
    return conn
  #獲取查詢結(jié)果集
  def fetch_all(self, sql):
    res = ''
    if(self._conn):
      try:
        self._cursor.execute(sql)
        res = self._cursor.fetchall()
      except Exception, data:
        res = False
        self._logger.warn("query database exception, %s" % data)
    return res
  def update(self, sql):
    flag = False
    if(self._conn):
      try:
        self._cursor.execute(sql)
        self._conn.commit()
        flag = True
      except Exception, data:
        flag = False
        self._logger.warn("update database exception, %s" % data)
    return flag
  #關(guān)閉數(shù)據(jù)庫連接
  def close(self):
    if(self._conn):
      try:
        if(type(self._cursor)=='object'):
          self._cursor.close()
        if(type(self._conn)=='object'):
          self._conn.close()
      except Exception, data:
        self._logger.warn("close database exception, %s,%s,%s" % (data, type(self._cursor), type(self._conn)))