"""
This is the sample code for TDengine python2 client.
"""
import taos
import sys
import datetime
import random

def exitProgram(conn):
 conn.close()
 sys.exit()

if __name__ == '__main__':
 start_time = datetime.datetime(2019, 7, 1)
 time_interval = datetime.timedelta(seconds=60)

 # Connect to TDengine server.
 # 
 # parameters:
 # @host : TDengine server IP address 
 # @user : Username used to connect to TDengine server
 # @password : Password 
 # @database : Database to use when connecting to TDengine server
 # @config : Configuration directory
 if len(sys.argv)>1:
 hostname=sys.argv[1]
 conn = taos.connect(host=hostname, user="root", password="taosdata", config="/etc/taos")
 else:
 conn = taos.connect(host="127.0.0.1", user="root", password="taosdata", config="/etc/taos")
 
 # Generate a cursor object to run SQL commands
 c1 = conn.cursor()
 # Create a database named db
 try:
 c1.execute('create database if not exists db ')
 except Exception as err:
 conn.close()
 raise(err)
 
 # use database
 try:
 c1.execute('use db')
 except Exception as err:
 conn.close()
 raise(err)


 # create table
 try:
 c1.execute('create table if not exists t (ts timestamp, a int, b float, c binary(20))')
 except Exception as err:
 conn.close()
 raise(err)

 # insert data 
 for i in range(10):
 try:
 value = c1.execute("insert into t values ('%s', %d, %f, '%s')" % (start_time, random.randint(1,10), random.randint(1,10)/10.0, 'hello'))
 #if insert, value is the affected rows
 print(value)
 except Exception as err:
 conn.close()
 raise(err)
 start_time += time_interval

 # query data and return data in the form of list
 try:
 c1.execute('select * from db.t')
 except Exception as err:
 conn.close()
 raise(err)

 # Column names are in c1.description list
 cols = c1.description
 # Use fetchall to fetch data in a list
 data = c1.fetchall()

 for col in data:
 print(col)

 print('Another query method ')

 try:
 c1.execute('select * from db.t')
 except Exception as err:
 conn.close()
 raise(err)

 # Use iterator to go through the retreived data
 for col in c1:
 print(col)

 conn.close()