Why I am not able to connect to the database - python-3.x

import lot_details, car_details
import numpy as np
import sqlite3
conn = sqlite3.connect('parkingLot.db')
c = conn.cursor()
class Parking(object):
"""
Parking class which has details about parking slots
as well as operation performed on parking are present here
"""
def __init__(self):
self.slots = {}
def create_parking_lot(self, no_of_slots):
try:
c.execute('CREATE TABLE IF NOT EXISTS parkingTable(slot_no REAL, reg_no TEXT, colour TEXT, total_time TEXT,charge TEXT)')
except Exception as ex:
print("Couldn't make a table in DB")
no_of_slots = int(no_of_slots)
if len(self.slots) > 0:
print ("Parking Lot already created")
return
if no_of_slots > 0:
for i in range(1, no_of_slots+1):
temp_slot = lot_details.PSlot(slot_no=i, available=True)
self.slots[i] = temp_slot
print ("Created a parking lot with {} slots" .format(no_of_slots))
else:
print ("Number of slots provided is incorrect.")
return
Using above code I am trying to create a database(which is successful) but now I am not able to create the Table inside it using the above command.
I tried doing it separately its working there. But, I am not able to create it using above code.

Depending on how and where you are creating the Parking object I suspect this could be a scoping issue, either pass the db connection into the constructor or just create it in the constructor itself. Code modified for brevity. The following works for me.
import sqlite3
class Parking(object):
def __init__(self):
self.slots = {}
self.conn = sqlite3.connect('parkingLot.db')
def create_parking_lot(self, no_of_slots):
try:
cur = self.conn.cursor()
cur.execute('CREATE TABLE IF NOT EXISTS parkingTable(slot_no REAL, reg_no TEXT, colour TEXT, total_time TEXT,charge TEXT)')
except Exception as ex:
print("Couldn't make a table in DB")
return
parking = Parking()
parking.create_parking_lot(5)

Related

How to do validation in python?

I am making a gui for employee management system using python tkinter and sqlite3.
In this gui user can add, view, delete amd update employee info.
def save():
con = None
try:
con = connect("pro.db")
cursor = con.cursor()
sql = "insert into Employee values('%d', '%s', '%f')"
id = int(aw_ent_id.get())
name = aw_ent_name.get()
lenstring = False
while not lenstring:
if len(name) >= 2:
lenstring = True
else:
showerror("error","Enter atleast 2 letters")
break
salary = float(aw_ent_salary.get())
cursor.execute(sql%(id, name, salary))
con.commit()
showinfo("success", "record added")
aw_ent_id.delete(0, END)
aw_ent_name.delete(0, END)
aw_ent_salary.delete(0, END)
aw_ent_id.focus()
except Exception as e:
con.rollback()
showerror("issue", e)
finally:
if con is not None:
con.close()
the code is running but i am getting some errors in validating name and salary.
for name i have done validating but its not working. I am getting an error
the data is getting saved even after getting error.
What should i do to make it right?
It is better to:
validate the inputs before saving to database
raise exception if len(name) is less than 2 instead of using while loop checking (actually the while loop is meaningless)
use placeholders to avoid SQL injection
Below is updated save():
# avoid using wildcard import
import tkinter as tk
from tkinter.messagebox import showinfo, showerror
import sqlite3
...
def save():
con = None
try:
# validate inputs
# use emp_id instead of id because id is built-in function
emp_id = int(aw_ent_id.get().strip()) # raise ValueError if not a valid integer
name = aw_ent_name.get().strip()
if len(name) < 2:
raise Exception('Name too short, at least 2 letters')
salary = float(aw_ent_salary.get().strip()) # raise ValueError if not a valid float number
# validations on inputs are passed, try saving to database
sql = 'insert into Employee values (?, ?, ?)' # use placeholders to avoid SQL injection
con = sqlite3.connect('pro.db')
cursor = con.cursor()
cursor.execute(sql, (emp_id, name, salary))
con.commit()
showinfo('Success', 'Employee added')
aw_ent_id.delete(0, tk.END)
aw_ent_name.delete(0, tk.END)
aw_ent_salary.delete(0, tk.END)
aw_ent_id.focus_set()
except Exception as e:
if con:
con.rollback()
showerror("Error", e)
finally:
if con:
con.close()
...

try to print some table is sqlite3 using python

hi I am a new in python i tried to create a new class that handle with sqlite3 in my read method i try to print some var but is does not print anything can you help me?
here is the code can you fix it and tell me what the problem is
class SQLite_class() :
file_name=''
table_sql_name =''
# con = sqlite3.connect(self.c)
def creat_file_name(self):
self.file_name = input("enter the SQL fille name !")
self.file_name = self.file_name+'.sqlite'
return self.file_name
def conncection(self):
conn = sqlite3.connect(self.file_name)
return conn
def creat_cursor(self):
conn = self.conncection()
cur = conn.cursor()
return cur
def del_table(self):
cur = self.creat_cursor()
cur.execute('DROP TABLE IF EXISTS '+self.table_sql)
def creat_table(self):
cur = self.creat_cursor()
#adding a new option (name of table of more we need to add some {} and use the format function)
cur.execute( '''CREATE TABLE IF NOT EXISTS {} (data TEXT, number INTEGER)'''.format(self.table_sql_name))
self.commiting()
def insrt(self):
cur = self.creat_cursor()
cur.execute('''INSERT INTO {} (data, number) VALUES (?, ?)'''.format(self.table_sql_name) ,('Thunderstruck', 20))
def close(self):
conn = self.conncection()
conn.close()
def commiting(self):
conn = self.conncection()
conn.commit()
def read(self):
cur = self.creat_cursor()
cur.execute('''SELECT data, number FROM {}'''.format(self.table_sql_name))
for row in cur: print(row)
test = SQLite_class()
test.creat_file_name()
test.table_sql_name = 'Track'
test.creat_table()
test.insrt()
test.commiting()
test.read()
test.commiting()
test.close()
This comment # con = sqlite3.connect(self.c) indicates you know what has to be done. I suspect when that didn't work, you went down the rabbit hole of creating connections everywhere. Program should make one db connection. Every time it makes a connection, it loses what came before.
It could declare conn = '', then call conncection() once (and remove it from the other methods; they'll probably need to take conn as an argument). It'll take some try, try again, but it will get you to a better place.
And don't forget to fetch the rows once the SELECT is executed.

python sqlite3 record is not inserting into the database with a placeholder function

this code is not inserting my list(self.list2) into the database 'main.db'. I read the the following posts already and they all seem to use the idea of using join() to create # of place holders based on the length of the list.
Dynamically creating a placeholder to insert many column values for a row in SQLite table
Inserting to sqlite dynamically with Python 3
the code is running without errors.
I tested the code by printing
return (f"{', '.join('?' * len(input))}")
and it prints "?, ?, ?, ? ", so I know the function works.
the database is created properly with the following code:
self.cursor.execute('''CREATE TABLE IF NOT EXISTS main
(T_num text Primary Key NOT NULL,
Name text NOT NULL,
Item1 text,
Item2 text,
Item3 text)''')
Maybe I missed a small detail, or I don't know how the return statement/function works.
Please help me to trouble shoot this. Thank you for any assistance.
import tkinter as tk
import sqlite3
class Model():
def __init__(self):
self.list1 = [('Table #', '6'), ('Name', 'Jenn'), ('Beef
Tacos', '6'), ("Fish Tacos", "6")]
self.list2 = list(map(": ".join, self.list1))
self.conn = sqlite3.connect("4th.db")
self.cursor=self.conn.cursor()
self.place_holder(self.list2)
def place_holder(self, input):
return (f"{', '.join('?' * len(input))}")
self.cursor.execute("INSERT INTO main VALUES (place_holder(input))", self.list2)
self.conn.commit()
self.conn.close()
if __name__ == "__main__":
c = Model()
You was trying to insert into db after return in your place_holder method which is not possible because the function exit after return. Also in your sql specify in which column you want to insert into.
like this
self.cursor.execute(f"INSERT INTO main (T_num, Name, Item1, Item2) VALUES {_placeholder}", self.list2)
There is your complete program, hope this will help you.
import tkinter as tk
import sqlite3
class Model():
def __init__(self):
self.list1 = [('Table #', '6'), ('Name', 'Jenn'), ('Beef Tacos', '6'), ("Fish Tacos", "6")]
self.list2 = list(map(": ".join, self.list1))
self.conn = sqlite3.connect("4th.db")
self.cursor = self.conn.cursor()
_placeholder = self.place_holder(self.list2)
# specify here in which column you want to insert the data
self.cursor.execute(f"INSERT INTO main (T_num, Name, Item1, Item2) VALUES {_placeholder}", self.list2)
self.conn.commit()
self.conn.close()
def place_holder(self, input_list):
'''Returns the place holder (?, ?, .....) as string'''
return f"({', '.join('?' * len(input_list))})"
if __name__ == "__main__":
c = Model()

Sqlalchemy filter by calculated datetime hybrid_property

I have a model Prescription.
from datetime import timedelta
from sqlalchemy.ext.hybrid import hybrid_property
class Prescription(db.Model):
""" docstring """
ID = db.column(db.Integer, primary_key=True)
date = db.Column(db.DateTime)
duration = db.Column(db.SmallInteger)
#hybrid_property
def expiration_date(self):
# return self.date + timedelta(days=self.duration)
return self.date + timedelta(days=7)
#classmethod
def actual(cls ):
""" docstring """
today = datetime.today()
return cls.query.filter(Prescription.expiration_date>=today)
I want to get only actual prescriptions in my actual method, and when I specify
#hybrid_property
def expiration_date(self):
return self.date + timedelta(days=7)
everything works like a charm.
But every prescription has a different duration, and when I specify
#hybrid_property
def expiration_date(self):
return self.date + timedelta(days=self.duration)
I've got an error
TypeError: unsupported type for timedelta days component: InstrumentedAttribute
I tried to make a little hack like this
#property
def days(self):
return int(self.duration)
but no luck.
Can anyone tell some workaround, or creating some lazy object for duration field or maybe another way get actual prescriptions, filtering by calculated expiration_date?
You might be trying to calculate a DATEDIFF:
Calculate DATEDIFF in POSTGRES using SQLAlchemy
Here, is_expired will generate a SQL query part which calculates difference in days between the start date and utcnow(), and compares the result with self.duration
This works in PostgreSQL, but I have not tested on other RDBMS.
from datetime import datetime
import sqlalchemy as sa
class Prescription:
ID = db.column(db.Integer, primary_key=True)
date = db.Column(db.DateTime)
duration = db.Column(db.SmallInteger)
#hybrid_property
def is_expired(self):
days_since_published = sa.func.trunc((
sa.extract('epoch', datetime.utcnow()) -
sa.extract('epoch', self.date)
) / 3600 / 24)
return days_since_published >= self.duration
#classmethod
def active(cls):
return cls.query.filter(is_expired=False)
In your #classmethod annotated actual() method, you are trying to access a non-static property(expiration_date) which is raising the error.
As per my understanding of what your code is doing, I have changed the code as follow:
from datetime import datetime,timedelta
from sqlalchemy.ext.hybrid import hybrid_property
from flask_sqlalchemy import SQLAlchemy
from flask import Flask
app = Flask(__name__)
db = SQLAlchemy(app)
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = True
app.config['SQLALCHEMY_DATABASE_URI'] ='sqlite:///'
class Prescription(db.Model):
""" docstring """
def mydefault(context):
return context.get_current_parameters()['date'] + timedelta(days=context.get_current_parameters()['duration'])
ID = db.Column(db.Integer,primary_key= True)
date = db.Column(db.Date)
duration = db.Column(db.SmallInteger)
expiration_date = db.Column(db.Date,default = mydefault)
#classmethod
def actual(cls ):
""" docstring """
today = datetime.today().date()
return cls.query.filter(Prescription.expiration_date>=today).all()
def __repr__(self):
return "Id:{} , date:{}, duration:{}, expiration_date:{}".format(self.ID,self.date,self.duration,self.expiration_date)
db.create_all()
q=Prescription(ID=1,date=datetime(2019,5,26).date(),duration = 1) #Expired
r=Prescription(ID=2,date=datetime(2019,5,20).date(),duration = 3) #Expired
s=Prescription(ID=3,date=datetime(2019,5,27).date(),duration = 5) #Not Expired
t = Prescription(ID=4,date=datetime.now().date(),duration = 1) #Not Expired
db.session.add(q)
db.session.add(r)
db.session.add(s)
db.session.add(t)
db.session.commit()
list_obj = Prescription.query.all()
print("All Objects in DB:-")
for l in list_obj:
print(l)
print()
print("Valid Prescription:")
print(Prescription.actual())
Output:
One thing I can suggest to you is since the model does not need the time of expiration.
So you could change
date = db.Column(db.DateTime)
to
date = db.Column(db.Date)
and it will ease your task :)

How to modify the PostgreSQL psycopg to accept variables instead of values

I am creating a dictionary attacking tool on PostgreSQL. The tool is inspired by the work of m8r0wn - enumdb tool. Mikes tool is aimed at MySQL and MSSQL. I aim to use the same approach he used but modify the actions and output file. The script should
1) Read a CSV file that contains targets and ports, one per line 127.0.0.1,3380.
2) when provided a list of usernames and/or passwords, it will cycle through each targeted host looking for valid credentials. By default, it will use newly discovered credentials to search for sensitive information in the host's databases via keyword searches on the table or column names.
3) This information can then be extracted and reported to a JSON, .csv or .xlsx output file.
I have a semi functional code, but I suspect the PostgreSQL connection function is not working due to the logic behind passing parameters. I am interested in suggestions on how best I could present the tools results as a JSON file.
I understand that in Python, we have several modules available to connect and work with PostgreSQL which include:
Psycopg2
pg8000
py-postgresql
PyGreSQL
ocpgdb
bpgsql
SQLAlchemy
see also https://www.a2hosting.co.za/kb/developer-corner/postgresql/connecting-to-postgresql-using-python
The connection methods I have tried include:
import psycopg2
from psycopg2 import Error
conn = psycopg2.connect(host=host, dbname=db_name, user=_user, password=_pass, port=port)
import pg
conn = pg.DB(host=args.hostname, user= _user, passwd= _pass)
sudo pip install pgdb
import pgdb
conn = pgdb.connect(host=args.hostname, user= _user, passwd= _pass)
I am not sure how to pass the different _user and _pass guesses into the pyscopg2 for instance, without breaking the code.
I have imported the following libraries
import re
import psycopg2
from psycopg2 import Error
import pgdb
#import MySQLdb
import pymssql
import argparse
from time import sleep
from sys import exit, argv
from getpass import getpass
from os import path, remove
from openpyxl import Workbook
from threading import Thread, activeCount
The PgSQL block is as follows:
##########################################
# PgSQL DB Class
##########################################
class pgsql():
def connect(self, host, port, user, passwd, verbose):
try:
con = pgdb.connect(host=host, port=port, user=user, password=passwd, connect_timeout=3)
con.query_timeout = 15
print_success("[*] Connection established {}:{}#{}".format(user,passwd,host))
return con
except Exception as e:
if verbose:
print_failure("[!] Login failed {}:{}#{}\t({})".format(user,passwd,host,e))
else:
print_failure("[!] Login failed {}:{}#{}".format(user, passwd, host))
return False
def db_query(self, con, cmd):
try:
cur = con.cursor()
cur.execute(cmd)
data = cur.fetchall()
cur.close()
except:
data = ''
return data
def get_databases(self, con):
databases = []
for x in self.db_query(con, 'SHOW DATABASES;'):
databases.append(x[0])
return databases
def get_tables(self, con, database):
tables = []
self.db_query(con, "USE {}".format(database))
for x in self.db_query(con, 'SHOW TABLES;'):
tables.append(x[0])
return tables
def get_columns(self, con, database, table):
# database var not used but kept to support mssql
columns = []
for x in self.db_query(con, 'SHOW COLUMNS FROM {}'.format(table)):
columns.append(x[0])
return columns
def get_data(self, con, database, table):
# database var not used but kept to support mssql
return self.db_query(con, 'SELECT * FROM {} LIMIT {}'.format(table, SELECT_LIMIT))
The MSSQL is as follows:
# MSSQL DB Class
class mssql():
def connect(self, host, port, user, passwd, verbose):
try:
con = pymssql.connect(server=host, port=port, user=user, password=passwd, login_timeout=3, timeout=15)
print_success("[*] Connection established {}:{}#{}".format(user,passwd,host))
return con
except Exception as e:
if verbose:
print_failure("[!] Login failed {}:{}#{}\t({})".format(user,passwd,host,e))
else:
print_failure("[!] Login failed {}:{}#{}".format(user, passwd, host))
return False
def db_query(self, con, cmd):
try:
cur = con.cursor()
cur.execute(cmd)
data = cur.fetchall()
cur.close()
except:
data = ''
return data
def get_databases(self, con):
databases = []
for x in self.db_query(con, 'SELECT NAME FROM sys.Databases;'):
databases.append(x[0])
return databases
def get_tables(self, con, database):
tables = []
for x in self.db_query(con, 'SELECT NAME FROM {}.sys.tables;'.format(database)):
tables.append(x[0])
return tables
def get_columns(self, con, database, table):
columns = []
for x in self.db_query(con, 'USE {};SELECT column_name FROM information_schema.columns WHERE table_name = \'{}\';'.format(database, table)):
columns.append(x[0])
return columns
def get_data(self, con, database, table):
return self.db_query(con, 'SELECT TOP({}) * FROM {}.dbo.{};'.format(SELECT_LIMIT, database, table))
The main function block:
def main(args):
try:
for t in args.target:
x = Thread(target=enum_db().db_main, args=(args, t,))
x.daemon = True
x.start()
# Do not exceed max threads
while activeCount() > args.max_threads:
sleep(0.001)
# Exit all threads before closing
while activeCount() > 1:
sleep(0.001)
except KeyboardInterrupt:
print("\n[!] Key Event Detected...\n\n")
exit(0)
if __name__ == '__main__':
version = '1.0.7'
try:
args = argparse.ArgumentParser(description=("""
{0} (v{1})
--------------------------------------------------
Brute force Juggernaut is a PgSQL brute forcing tool.**""").format(argv[0], version), formatter_class=argparse.RawTextHelpFormatter, usage=argparse.SUPPRESS)
user = args.add_mutually_exclusive_group(required=True)
user.add_argument('-u', dest='users', type=str, action='append', help='Single username')
user.add_argument('-U', dest='users', default=False, type=lambda x: file_exists(args, x), help='Users.txt file')
passwd = args.add_mutually_exclusive_group()
passwd.add_argument('-p', dest='passwords', action='append', default=[], help='Single password')
passwd.add_argument('-P', dest='passwords', default=False, type=lambda x: file_exists(args, x), help='Password.txt file')
args.add_argument('-threads', dest='max_threads', type=int, default=3, help='Max threads (Default: 3)')
args.add_argument('-port', dest='port', type=int, default=0, help='Specify non-standard port')
args.add_argument('-r', '-report', dest='report', type=str, default=False, help='Output Report: csv, xlsx (Default: None)')
args.add_argument('-t', dest='dbtype', type=str, required=True, help='Database types currently supported: mssql, pgsql')
args.add_argument('-c', '-columns', dest="column_search", action='store_true', help="Search for key words in column names (Default: table names)")
args.add_argument('-v', dest="verbose", action='store_true', help="Show failed login notices & keyword matches with Empty data sets")
args.add_argument('-brute', dest="brute", action='store_true', help='Brute force only, do not enumerate')
args.add_argument(dest='target', nargs='+', help='Target database server(s)')
args = args.parse_args()
# Put target input into an array
args.target = list_targets(args.target[0])
# Get Password if not provided
if not args.passwords:
args.passwords = [getpass("Enter password, or continue with null-value: ")]
# Define default port based on dbtype
if args.port == 0: args.port = default_port(args.dbtype)
# Launch Main
print("\nStarting enumdb v{}\n".format(version) + "-" * 25)
main(args)
except KeyboardInterrupt:
print("\n[!] Key Event Detected...\n\n")
exit(0)
I am aware that documentation states here http://initd.org/psycopg/docs/module.html states about how connection parameters can be specified. I would like to pass password guesses into the brute class and recursively try different combinations.
PEP-8 asks that you please give classes a name
starting with a capital letter, e.g. Pgsql.
You mentioned that the pgsql connect() method is not working properly,
but didn't offer any diagnostics such as a stack trace.
You seem to be working too hard, given that the sqlalchemy layer
has already addressed the DB porting issue quite nicely.
Just assemble a connect string starting with
the name of the appropriate DB package,
and let sqlalchemy take care of the rest.
All your methods accept con as an argument.
You really want to factor that out as the object attribute self.con.
The db_query() method apparently assumes that
arguments for WHERE clauses already appear, properly quoted, in cmd.
According to Little Bobby's mother,
it makes sense to accept query args according to the API,
rather than worrying about potential for SQL injection.

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