Unable to read mysql through Jyputer in docker containers (error: DatabaseError: 2005 (HY000): Unknown MySQL server host 'localhost:3306' (22)) - mysql

Question

My code is as follows:
import mysql.connector
mydb = mysql.connector.connect(host="localhost:3306",user="root",password="example")
print("Connected")
Docker compose for mysql and jyputer files:
# Use root/example as user/password credentials
version: '3.1'
services:
db:
image: mysql
command: --default-authentication-plugin=mysql_native_password
restart: always
environment:
MYSQL_ROOT_PASSWORD: example
AWS_ACCESS_KEY_ID: "A"
AWS_SECRET_ACCESS_KEY: "k"
adminer:
image: adminer
restart: always
ports:
- 8080:8080
jyputer:
version: "3"
services:
pyspark:
image: "jupyter/all-spark-notebook"
volumes:
- c:/code/pyspark-data:/home/jovyan
ports:
- 8888:8888
environment:
AWS_ACCESS_KEY_ID: "5H"
AWS_SECRET_ACCESS_KEY: "0oRBJk"
I have also created a network and kept all containers under one network, by using this command
docker network connect mynetwork 929cd60b08df
Error Received while execuitng in jyputer network:
DatabaseError: 2005 (HY000): Unknown MySQL server host 'localhost:3306' (22)
What have I tried:
mysql error 2005 - Unknown MySQL server host 'localhost'(11001)
127.0.0.1 localhost
this netry is already there in etc/hosts folder. Dont know what to do now

Answer 1

When you created a network you need to connect both containers
docker network create mynetwork
docker network connect mynetwork db_container_id
docker network connect mynetwork pyspark_container_id
Then get its config
docker network inspect mynetwork
It gives an IP addresses of this bridge network
[
{
"Name": "t11",
"Id": "bb203079ab3e48badacb3bb53181dd6871b2f60f22b4079729bc069e1739bbe0",
"Created": "2021-05-21T04:46:48.591105541Z",
"Scope": "local",
"Driver": "bridge",
"EnableIPv6": false,
"IPAM": {
"Driver": "default",
"Options": {},
"Config": [
{
"Subnet": "172.28.0.0/16",
"Gateway": "172.28.0.1"
}
]
},
"Internal": false,
"Attachable": false,
"Ingress": false,
"ConfigFrom": {
"Network": ""
},
"ConfigOnly": false,
"Containers": {
"3ff678e8ddeb600b1af38a06dda053c8bf6544b136bfca91363379df1d40c69a": {
"Name": "t1_db_1",
"EndpointID": "deefd7c8a187b9513fd074f9632f961312a3bdaa8aa568be6223f3d301389808",
"MacAddress": "02:42:ac:1c:00:03",
"IPv4Address": "172.28.0.3/16",
"IPv6Address": ""
},
"9c95f68416586d3f1a87376a4a669df834d7b25eb22e3b3f33afb0ce1918d6cc": {
"Name": "t2_pyspark_1",
"EndpointID": "0fcbf15530f5b0a526c2036d26890e087f3becdd6eae1896e58a6a67efe2f676",
"MacAddress": "02:42:ac:1c:00:02",
"IPv4Address": "172.28.0.2/16",
"IPv6Address": ""
}
},
"Options": {},
"Labels": {}
}
]
you need IP of db container, in this example it's 172.28.0.3
go with it
mydb = mysql.connector.connect(port="3306", host="172.28.0.3", user="root", password="example")
print("Connected")
cursor = mydb.cursor()
query = ("select 1;")
cursor.execute(query)
for r in cursor:
print(r)
cursor.close()