ssh first with mysqldb in python - python

I'm trying to connect to a MySQL database on a remote server using MySQLdb in python. The problem is that first I need to SSH into the host, and then from there, I need to connect to the MySQL server. The problem I'm having, though, is that MySQLdb does not seem to have a way of establishing an SSH connection before connecting to the SQL server. I've checked the documentation but have not had any luck.
This is how I'm connecting:
conn = MySQLdb.connect(host = 'mysqlhost.domain.com:3306', user = 'user', passwd = 'password', db = 'dbname')
But what I really need is something like this:
conn = MySQLdb.connect(sshhost = 'sshhost.domain.com', sshuser = 'sshusername', sshpasswd = 'sshpasswd', host = 'mysqlhost.domain.com:3306', user = 'user', passwd = 'password', db = 'dbname')
Which is of course just made up. Can anyone make any recommendations?


I prefer keeping the tunnel within the python code, I did hate to create tunnels manually, or separately, thanks to sshtunnel library its very simple to use.
Here is some simple sample that will work for what you want.
import MySQLdb
from sshtunnel import SSHTunnelForwarder
with SSHTunnelForwarder(
('sshhost.domain.com', 22),
ssh_password="sshpasswd",
ssh_username="sshusername",
remote_bind_address=('mysqlhost.domain.com', 3306)) as server:
conn = MySQLdb.connect(host='127.0.0.1',
port=server.local_bind_port,
user='user',
passwd='password',
db='dbname')


Setup an ssh tunnel before you use MySQLdb.connect. The tunnel will make it appear as though you have the mysql running locally, set it up something like this
ssh user#host.com -L 9990:localhost:3306
here your local port 9990 will bind to 3306 on the remote host, -L stands for local, then 9990:localhost:3306 means LOCALPORT:
conn = MySQLdb.connect(host = 'mysqlhost.domain.com:9990', user = 'user', passwd = 'password', db = 'dbname')
notice the 9990.
Add your public ssh key of user to the host.com so that you dont have to type the password each time you want to setup the tunnel (use public key authentication).
If you need to do this within python there is python-to-ssh binding libraries you could call from within python to setup the tunnel for you.

Related

Issue Connecting to GCP SQL with python-mysql: don't want to use a port

`db = MySQLdb.connect(
host = '12.34.567.891',
user = 'root',
passwd = '',
db = 'testdb',
port = "something-that-works")`
Very Simple Can I somehow make it so that it connects only to the ip '12.34.567.891'. Google is forwarding the port to 80 but you can't request port 80 or it ends up in an endless loop.
port=null or port = none will cause and error.
I have no issues connecting from my cli mysql client
Thank you,
I expected to be able to connect to the server no issues if I am able to do so from my cli - I need some way to send the connecting request to the raw IP no port. It may be possible python-mysql can't do this

3306 is the default MySQL port and it seems that you are using MySQL, so that should work. https://cloud.google.com/sql/docs/mysql/connect-overview

You will have an easier time connecting with the Cloud SQL Python Connector a library built purely for connecting to Cloud SQL with Python.
Looks like this:
from google.cloud.sql.connector import Connector
# build connection
def getconn() -> pymysql.connections.Connection:
with Connector() as connector:
conn = connector.connect(
"project:region:instance", # Cloud SQL instance connection name
"pymysql",
user="my-user",
password="my-password",
db="my-db-name"
)
return conn
# create connection pool
pool = sqlalchemy.create_engine(
"mysql+pymysql://",
creator=getconn,
)
# insert statement
insert_stmt = sqlalchemy.text(
"INSERT INTO my_table (id, title) VALUES (:id, :title)",
)
# interact with Cloud SQL database using connection pool
with pool.connect() as db_conn:
# insert into database
db_conn.execute(insert_stmt, id="book1", title="Book One")
# query database
result = db_conn.execute("SELECT * from my_table").fetchall()
# Do something with the results
for row in result:
print(row)

Why doesn't it connect to the database remotely Python?

I am writing an online application. Rented hosting on TimeWeb, created a database on the hosting. I successfully connected to it using Putty, but the problem is that I need to connect using pycharm. Don't be surprised that I'm making an ssh connection here, and not in the ssh terminal of pycharm, I'm just planning to create an .exe file.I tried to specify port 3306 and utf8 encoding, but it still didn't help. So what's my mistake?
import paramiko
import pymysql
host = "x.x.x.x"
port = 22
username ="cv86943"
password = "xxxxxx"
ssh = paramiko.SSHClient()
ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
ssh.connect(host,port,username,password)
print("1") #1 writes, so the connection to the hosting is successful
conn = pymysql.connect(host = "localhost",user = "cv86943_letter", password = "12345678", db = "cv86943_letter")
print("2") #But 2 does not write anymore
ssh.close()
UPD: returns an error
pymysql.err.OperationalError: (2003, "Can't connect to MySQL server on 'localhost' ([WinError 10061]...)

Can you connect to a database on another pc?

I'm using MySQLdb for python, and I would like to connect to a database hosted on an other PC on the same network/LAN.
I tried the followings for host:
192.168.5.37
192.168.5.37:3306
http://192.168.5.37
http://192.168.5.37:3306
None of the above work, I always get the
2005, Unknown MySQL server host ... (0)
What might be the problem?
Code:
db = MySQLdb.connect(host="192.168.5.37", user = "root" passwd = "password", db = "test1")

You can use MySQL Connector/Python, a standardized database driver for Python.
You must provide username, password, host, database name.
import mysql.connector
conn = mysql.connector.connect(user=username, password=password,
host="192.168.5.37",
database=databaseName)
conn.close()
You can download it from: https://dev.mysql.com/downloads/connector/python/

The IP you posted are local IPs
Give it a try with your external IP (for example on this website)
https://www.whatismyip.com/
If it works with the external IP, then it's maybe a misconfiguration of your firewall.

Connect postgres and Python

I have a database available on a remote host. When I use putty and SSH, I am able to access it. The database itself has no password. Only, the SSH connection has a password. But, when I try to connect to it using Python, it asks for password. I'm new to postgres and paramiko.
Here's what I've tried:
import psycopg2
import paramiko
import time
t = paramiko.Transport(('xxx.com', 22))
t.connect(username="xxx", password='xxx')
c = paramiko.Channel(t)
conn = psycopg2.connect("dbname='xxx'")
curs = conn.cursor()
sql = "select * from xxx"
curs.execute(sql)
rows = curs.fetchall()
print(rows)
Other method that I tried was:
import os, psycopg2
os.system("ssh xxx#xxx.com -fNL 5432:localhost:5432 -p 22")
while True:
try:
conn = psycopg2.connect("dbname='xxx'")
curs = conn.cursor()
sql = "select * from xxx"
curs.execute(sql)
rows = curs.fetchall()
print(rows)
except:
print "I am unable to connect to the database"
This gives me a 'Could not request local forwarding' error.
Is there some other way to go about this?
I have a Windows 7 (x64) machine with Python 2.7. Please help me. Thanks.

You should connect to the remote server and make port forwarding of remote PostgreSQL to a local port.
Without paramiko, it's something like this:
# start port forwarding
$ ssh -L PGSQL_LOCAL_PORT:localhost:PGSQL_REMOTE_PORT user#xxx.com
# in python
psycopg.connect("dbname='xxx' host='localhost' port='PGSQL_LOCAL_PORT'")
Here is an example of doing this with paramiko
https://code.ros.org/trac/wg-ros-pkg/browser/pkg/trunk/paramiko/demos/forward.py?rev=30
Note: Port forwarding is blocking operation. So, you have to start port forwarding in separate thread/process.

PyMySQL can't connect to MySQL on localhost

I'm trying to connect to MySQL on localhost using PyMySQL:
import pymysql
conn = pymysql.connect(db='base', user='root', passwd='pwd', host='localhost')
but (both on Python 2.7 and Python 3.2) I get the error:
socket.error: [Errno 111] Connection refused
pymysql.err.OperationalError: (2003, "Can't connect to MySQL server on 'localhost' (111)")
I'm sure mysqld is running because I can connect using mysql command or phpMyAdmin. Moreover, I can connect using MySQLdb on Python 2 with nearly the same code:
import MySQLdb
conn = MySQLdb.connect(db='base', user='root', passwd='pwd', host='localhost')
It seems that the problem is on PyMySQL side rather than MySQL but I have no idea how to solve it.

Two guesses:
Run mysqladmin variables | grep socket to get where the socket is located, and try setting up a connection like so:
pymysql.connect(db='base', user='root', passwd='pwd', unix_socket="/tmp/mysql.sock")
Run mysqladmin variables | grep port and verify that the port is 3306. If not, you can set the port manually like so:
pymysql.connect(db='base', user='root', passwd='pwd', host='localhost', port=XXXX)

Seems like changing localhost to 127.0.0.1 fixes the error, at least in my configuration.
If it doesn't, I would look for errors in tcp sockets connection and, of course, post it as a bug in pymysql bugtrack.

I solved the issue by replacing localhost with 127.0.0.1 and changing the password to my MYSQL database password as shown below;
conn = pymysql.connect(
host = '127.0.0.1',
port = 3306,
user = 'root',
passwd = 'XXXXXXXXX',
db = 'mysql'
)

I met the same question and my solution is as follows:
Run ssh -fN -L 3307:mysql_host:3306 ssh_user#ssh_host in my terminal.
Then input your ssh password
conn = pymysql.connect(db='base', user='root', passwd='pwd', host='localhost')
This error occurs because database does not support link directly.

I asked why socket worked but not TCP and the answer was that bind-address in /etc/my.cnf was not set correctly. This could be your problem too since the socket methods works just fine but the TCP one does not.

Those who are strugging to connect localhost MySQL from dockerised flask-sqlalchemy or using pymysql, pls look into this thread, very usefull How to connect locally hosted MySQL database with the docker container

This worked for me:
import pymysql
db = pymysql.connect(host="localhost",port=8889,user="root",passwd="root")
cursor=db.cursor()
cursor.execute("SHOW DATABASES")
results=cursor.fetchall()
for result in results:
print (result)
if you want to find the port # go to mysql in terminal, and type:
SHOW VARIABLES WHERE Variable_name = 'hostname';
SHOW VARIABLES WHERE Variable_name = 'port';

I had this same problem on AWS - and turns out that my security group was blocking the connection. I temporarily opened up all connections and voila! It connected!
Do you have any type of FW or host-based FW that could be blocking the connection? I thought it was my code and all was fine. Also check the port you are connecting on.

If you are using Docker, you might need to use host.docker.internal instead of localhost.

I managed to solve my issue by using the port without any quotation like so:
port = 3306,

You need to add the port to the connection as well. Try this and it works fine.
pymysql(Module Name).connect(host="localhost", user="root", passwd="root", port=8889, db="db_name")

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