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Want to run mysql from Docker and connect with springboot

I continuously face the error:
Caused by: com.mysql.cj.exceptions.CJCommunicationsException: Communications link failure
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server
Caused by: java.net.UnknownHostException: No such host is known (mysql-standalone)
At first I create database from docker with the code:
docker run --name mysql-standalone -e MYSQL_ROOT_PASSWORD=password -e MYSQL_DATABASE=digitalprofile -e MYSQL_USER=sa -e MYSQL_PASSWORD=password mysql:5.6
After running it container is up
docker container ls
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
80584bfdf76c mysql:5.6 "docker-entrypoint.s…" 23 minutes ago Up 23 minutes 3306/tcp mysql-standalone
In appilcation.properties in eclipse
spring.jpa.hibernate.ddl-auto=update
spring.datasource.url=jdbc:mysql://mysql-standalone:3306/digitalprofile
spring.datasource.username=sa
spring.datasource.password=password
server.port=9090

spring.datasource.url=jdbc:mysql://localhost or ip address?:3306/digitalprofile

Running Spring Boot docker instance with Postgres docker instance

I'm attempting to run a Spring Boot app that connects a Postgres DB using:
docker-compose.yml (for Postgres) :
version: '3'
services:
postgres-db:
container_name: postgres-db
image: postgres:latest
restart: always
ports:
- "5432:5432"
environment:
POSTGRES_USER: my_user
POSTGRES_PASSWORD: my_password
POSTGRES_DB: shorten-db
To run the Postgres DB:
docker-compose up
.Dockerfile (for the Spring Boot app) :
FROM openjdk:12-jdk-alpine
RUN addgroup -S spring && adduser -S spring -G spring
USER spring:spring
ARG JAR_FILE=target/*.jar
COPY ${JAR_FILE} app.jar
ENTRYPOINT ["java","-jar","/app.jar"]
In order to run the Spring app using Docker I use:
mvn package
docker build -t url-shorten/url-shorten-docker .
docker run -p 8080:8080 url-shorten/url-shorten-docker
But I receive the error when starting when running above docker command:
Caused by: org.postgresql.util.PSQLException: Connection to localhost:5432 refused. Check that the hostname and port are correct and that the postmaster is accepting TCP/IP connections.
In Spring application.properties I connect to the DB using:
spring.datasource.url=jdbc:postgresql://localhost:5432/shorten-db
I think this error is due to the Spring Boot app is running in a different container to DB so it cannot find the DB on localhost. Is there an idiomatic way of connecting the Spring Book docker container to the DB container. Or do I have do access the IP address of my machine and use this address to connect to the Postgres DB running on Docker?

Yes, you can't use localhost in this situation
spring.datasource.url=jdbc:postgresql://postgres-db:5432/shorten-db

In Spring application.properties, try to change DB config to:
spring.datasource.url=jdbc:postgresql://postgres-db:5432/shorten-db
In container networks, You need to use the container name as a host.

You can add both DB and app containers to one Docker network and change PostgreSQL host in datasource URL to postgres-db. Then Spring app will work with your DB.

Cannot access docker postgres image via intellij and quarkus?

I run a docker postgres container via command line:
docker run --name some-postgres -p 5432:5432 -e POSTGRES_PASSWORD=passme -d postgres
But in IntelliJ I can't access this container
The following error message occurs:
[08001] Connection to localhost:5432 refused. Check that the hostname and port are correct and that the postmaster is accepting TCP/IP connections.
java.net.ConnectException: Connection refused: connect.
Do you know any problem, maybe with the port?

Connection refused: accessing a spring boot application running in docker container

I have my spring boot application and mysql database running in separate docker containers. I am able to access server database from my host.
My application.properties for Spring boot application looks like below:
spring.datasource.url=jdbc:mysql://benefitsmysql:3308/benefitsmysql
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.jpa.show-sql=true
spring.jpa.properties.hibernate.dialect = org.hibernate.dialect.MySQL5Dialect
# ====================================================================================
# = SSL Configuration
# ====================================================================================
#security.basic.enabled=false
server.port=8443
server.ssl.key-store=keystore.jks
server.ssl.key-store-password=*******
server.ssl.keyStoreType=jks
server.ssl.keyAlias=tomcatselfsigned
I am building a docker container image by using maven plugin for docker. My Dockerfile looks like below:
FROM java:8
VOLUME /tmp
ADD Benefits.jar Benefits.jar
EXPOSE 8443
RUN bash -c 'touch /Benefits.jar'
ENTRYPOINT ["java","-Djava.security.egd=file:/dev/./urandom","-jar","/Benefits.jar"]
I am starting docker container for spring boot application like below:
docker run -p 8443:8443 --name benefits --link benefitsmysql:mysql -d c794a4d0c634
and if I do docker ps -a, I get following output
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
8070c575b6dd c794a4d0c634 "java -Djava.secur..." 2 minutes ago Up 2 minutes 0.0.0.0:8443->8443/tcp benefits
aa417df08b94 mysql:5.6 "docker-entrypoint..." 2 days ago Up 2 days 0.0.0.0:3308->3306/tcp benefitsmysql
f55a2a7ac487 hello-world "/hello" 2 days ago Exited (0) 2 days ago gifted_lalande
Now when I access my spring boot application running inside docker container from my windows machine like https://192.168.99.103:8443/home, I get connection refused error ERR_CONNECTION_REFUSED.
What am I missing in this configuration?

yogsma
I read your blog, and apply your solve, but docker-machine ip didn't solve my problem.
Then I realize docker containers can't communicate with 127.0.0.1 and I use their container ip
docker inspect <container_id>
then find IpAddress.
This ip address is solves my problem.I dont need to use docker-machine ip

Connecting to postgres from a docker container

I'm a little lost as to why my java application can't connect to my postgres database. I'm aiming to connect to a postgres database through jdbc. The application is to run inside a docker container.
this.connection = `DriverManager.getConnection("jdbc:postgresql://<myip>:5432/databasename", "usr", "password");`
I'm getting the exception:
Connection refused. Check that the hostname and port are correct and that the postmaster is accepting TCP/IP connections.
When I run the application from my desktop, it connects as expected. When I run it from within the docker container, it fails.
I've just installed docker this afternoon and ran through the getting started for windows, so my setup state is just after running that. Here's the contents of my Dockerfile:
FROM java:8
ADD VaultServer /
EXPOSE 3971
EXPOSE 3972
ENTRYPOINT ["java", "-jar", "VaultServer.jar"]

Inside the data folder there is a file called pg_hba.conf you have to configure it to accept the connections. So your pg_hba.conf file should have a line like this
host all all YourDockerip/24 md5.
After that configure the postgresql.conf file. You have to update the listen_addresses to all and make sure to uncomment that line by removing the # mark. So your listen_addresses should look like this listen_addresses = '*'.