I am trying to access MySQL on GCE VM instance through Google Colaboratory though, unfortunately, it does not work properly but does work in the local VSCode environment.
While executing TestExec.py, it shows SSH Connected so it seems that ssh connection is successfully done though, however, it seems to be stuck on MySQL connection.
Output on Google Colab:
Please help with the solutions/tips?
sqlList = []
sqlList.append("select * from table name;")
HOST = 'ComputeEngine PublicIP'
PORT = 22
USER = 'username'
DBUSER = 'username for db'
KEY_FILE = 'private key file path'
DBNAME = 'dbname'
DBPORT = 3306
SSH_BASTION_ADDRESS = HOST
SSH_PORT = PORT
SSH_USER = USER
SSH_PKEY_PATH = KEY_FILE
MYSQL_HOST = HOST
MYSQL_PORT = 3306
MYSQL_USER = DBUSER
MYSQL_PASS = 'MySQL Login PW'
MYSQL_DB = DBNAME
with SSHTunnelForwarder(
(SSH_BASTION_ADDRESS, SSH_PORT),
ssh_pkey=SSH_PKEY_PATH,
ssh_username=SSH_USER,
# ssh_password=PASSPHRASE,
remote_bind_address=('localhost', MYSQL_PORT),
local_bind_address=('localhost', MYSQL_PORT)
) as ssh:
print("SSH Connected")
print(ssh.local_bind_port)
try:
connection = mysql.connector.connect(
host='localhost',
port = ssh.local_bind_port,
user=MYSQL_USER,
passwd=MYSQL_PASS,
db=MYSQL_DB,
charset='utf8'
)
print(connection.is_connected())
print("DB Connected")
cur = connection.cursor()
sql = "use dbname"
cur.execute(sql)
# rows = cur.fetchall()
# for row in rows:
# print(row)
for i in range(len(sqlList)):
print(sqlList[i])
sql = str(sqlList[i])
# sql = 'create table test (id int, content varchar(32))'
cur.execute(sql)
rows = cur.fetchall()
for row in rows:
print(row)
except mysql.connector.Error as err:
print("Something went wrong: {}".format(err))
connection.rollback()
raise err
finally:
cur.close()
connection.commit()
connection.close()
It seemed the error occurred because of the connection. I have changed the method of connection.
import pymysql.cursors
connection = pymysql.connect(
host='localhost',
user='user',
password='password!',
db='dbname',
charset='utf8mb4',
cursorclass=pymysql.cursors.DictCursor
)
Related
I'm trying to create a table in mySQL server running on pythonAnywhere from my local machine.
I followed the getting started guide, https://help.pythonanywhere.com/pages/AccessingMySQLFromOutsidePythonAnywhere, but I'm running into a OperationalError: (2013, 'Lost connection to MySQL server during query').
Here is my code:
import MySQLdb
import sshtunnel
sshtunnel.SSH_TIMEOUT = 10
sshtunnel.TUNNEL_TIMEOUT = 10
with sshtunnel.SSHTunnelForwarder(
('ssh.pythonanywhere.com'),
ssh_username='MyUSERNAME', ssh_password='***',
remote_bind_address=('MyUSERNAME.mysql.pythonanywhere-services.com', 3306)
) as tunnel:
connection = MySQLdb.connect(
user='MyUSERNAME',
passwd='***',
host='127.0.0.1', port=tunnel.local_bind_port,
db='MyUSERNAME$liveSports',
)
cur = connection.cursor()
with connection:
cur.execute("CREATE TABLE table_one (date TEXT, start_time TEXT)")
I'm not sure why I'm getting this error, or how to resolve it.
Similar errors, Lost connection to MySQL server during query , suggest that either I'm sending an incorrect query to my server, but as far as I know this is a valid query, or that my packet is too large, which I don't believe an empty table would be.
I'm new to SQL, but I can't seem to find an answer to this question.
You must leave the tunnel open. This is the easy way:
import MySQLdb
import sshtunnel
sshtunnel.SSH_TIMEOUT = 10
sshtunnel.TUNNEL_TIMEOUT = 10
tunnel = sshtunnel.SSHTunnelForwarder(
('ssh.pythonanywhere.com'),
ssh_username='MyUSERNAME', ssh_password='***',
remote_bind_address=('MyUSERNAME.mysql.pythonanywhere-services.com', 3306)
)
connection = MySQLdb.connect(
user='MyUSERNAME',
passwd='***',
host='127.0.0.1', port=tunnel.local_bind_port,
db='MyUSERNAME$liveSports',
)
cur = connection.cursor()
cur.execute("CREATE TABLE table_one (date TEXT, start_time TEXT)")
You could put all of your database stuff in a function and use
with sshtunnel.SSHTunnelForwarder(
('ssh.pythonanywhere.com'),
ssh_username='MyUSERNAME', ssh_password='***',
remote_bind_address=('MyUSERNAME.mysql.pythonanywhere-services.com', 3306)
) as tunnel:
do_all_processing()
def do_all_processing():
connection = MySQLdb.connect(
user='MyUSERNAME',
passwd='***',
host='127.0.0.1', port=tunnel.local_bind_port,
db='MyUSERNAME$liveSports',
)
...etc...
I prepared two VM instance with Compute Engine on GCP.
ServerA: Data processing and read/write to SQL(mysql) on ServerB.
ServerB: SQL Server (f1-micro* This is not Cloud SQL, but normal VM instance.)
Trying to access SSH from A to B in order to read/write DB on ServerB with the code below.
error code
error: ERROR | Problem setting SSH Forwarder up: Couldn't open tunnel localhost:3306 <> localhost:3306 might be in use or destination not reachable
sshtunnel.HandlerSSHTunnelForwarderError: An error occurred while opening tunnels.
#SSH connection
with SSHTunnelForwarder(
('PublicIP of ServerA', 22),
ssh_pkey=SSH_PKEY_PATH,
ssh_username=SSH_USER,
remote_bind_address=('localhost', 3306),
local_bind_address=('localhost', 3306)
) as ssh:
try:
#DB connection
connection = mysql.connector.connect(
host='localhost',
port = 3306,
user=MYSQL_USER,
passwd=MYSQL_PASS,
db=MYSQL_DB,
charset='utf8'
)
# print(connection.is_connected())
# Get Cur
cur = connection.cursor()
sql = "use dbname"
cur.execute(sql)
for i in range(len(sqlList)):
print("DB Access：" + str(sqlList[i]))
sql = str(sqlList[i])
# sql = 'create table test (id int, content varchar(32))'
cur.execute(sql)
sqlOUTPUT = cur.fetchall()
# rows = cur.fetchall()
# for row in rows:
# print(row)
except mysql.connector.Error as err:
print("Something went wrong: {}".format(err))
connection.rollback()
raise err
finally:
#Cur close
cur.close()
# Commit
connection.commit()
#DB Connection close
connection.close()
return sqlOUTPUT
But after "local_bind_address=(localhost, MYSQL_PORT)", an error occurs despite it goes through with the same code and same private key on the shell of B or on VSCode local environment.
I don't understand why it goes through with same code using shell and VSCode although it doesn't work on GCE.
Any help?
You might be able to debug this further and discard any issues with sshtunnel if you try to create the tunnel outside of the script from the client VM, with:
$ gcloud compute ssh server-a --zone=your-zone --ssh-flag='-NL 3306:127.0.0.1:3306' &
Then attempt a connection with:
$ mysql -h 127.0.0.1
I am trying to delete some record from mysql database using pymysql but i couldn't able to do.The same command if i execute in mysql its working.
logger = logging.getLogger()
logger.setLevel(logging.INFO)
# Connect to the MYSQL database
logger.info("Connecting to MySQL database")
try:
conn = pymysql.connect(host=rds_host, user=name, passwd=password, database=db_name, cursorclass=pymysql.cursors.DictCursor)
cur = conn.cursor()
except:
logger.error("ERROR: Unexpected error: Could not connect to MySql instance.")
sys.exit()
logger.info("SUCCESS: Connection to MySQL database succeeded")
def _clean_general_logs():
cur.execute(
"DELETE FROM desker.general_log WHERE event_time <= '2019-08-12 04:36:42.457536' ORDER BY event_time DESC limit 10")
conn.commit()
cur.close()
conn.close()
return {"result": True}
The problem is that I can't connect to localhost database (5432 port), I'm really green on this Postgresql and I still don't understand these databases and how they do work. My code for connection :
import psycopg2
try:
connection = psycopg2.connect(user = "sysadmin",
password = "pynative##29",
host = "127.0.0.1",
port = "5432",
database = "postgres_db")
cursor = connection.cursor()
# Print PostgreSQL Connection properties
print ( connection.get_dsn_parameters(),"\n")
# Print PostgreSQL version
cursor.execute("SELECT version();")
record = cursor.fetchone()
print("You are connected to - ", record,"\n")
except (Exception, psycopg2.Error) as error :
print ("Error while connecting to PostgreSQL", error)
finally:
#closing database connection.
if(connection):
cursor.close()
connection.close()
print("PostgreSQL connection is closed")
Also I did some port forwarding on my localhost rooter.
Port Forwarding photo
And I used the 'nmap' software for ports that are running as i understand? The results I got are here NMAP
I am having a weird issue with my python script. My script has to connect to MySQL DB. This is the code:
try:
conn = MySQLdb.connect( user='root', host = 'localhost')
cursor = conn.cursor()
databases = cursor.fetchall()
cursor.close()
except Exception as e:
print e
when I run this script I have and error like:
(1045, "Access denied for user 'root'#'localhost' (using password: NO")
in the other hand, I can connect to MySQL just by entering MySQL (without password).
Why am I having this error with my python script when there is no password to root user?
Provide empty password
try this
conn = MySQLdb.connect( user='root', host = 'localhost', passwd='')
This should be the syntax. You should have the MySql connector for Python
import mysql.connector
cnx = mysql.connector.connect(user='root', password='',
host='127.0.0.1',
database='database_name')
cnx.close()
try this (inside the bloc try except)
import mysql.connector
conn = mysql.connector.connect(user='root', password='',host='localhost',
database='your_database_name')
conn.close()