How to connect external Mysql from docker build

Docker Engine General
1

mysql and docker both are installed on the same machine.

But while connecting to the databse through docker image (db configurations are configured in the docker image; spring boot application)
| … 58 common frames omitted
apigateway_1 | Caused by: java.net.ConnectException: Connection refused (Connection refused)
apigateway_1 | at java.net.PlainSocketImpl.socketConnect(Native Method) ~[na:1.8.0_302]

2

Good evening,

while you connect from a non-dockerized application to the database running on the same computer using localhost or 127.0.0.1 this will not work if you try to connect from within a docker-container to a database running outside of the same docker-container.
But you can connect to 172.17.0.1 (the host-computer’s IP-address in Docker’s default network on a linux-machine) or host.docker.internal (the same for Docker on Windows) from within a Docker-container to connect to a service running on your host-computer.

Keep in mind that you may
…need to adjust firewall-rules on your host-computer
…have to configure your database to not only listen to 127.0.0.1 but on other interfaces, too
…check that the rights granted to your database-user are also valid to connect from other hosts than 127.0.0.1 or localhost as you are really connecting from a different source-ip-address.

3

@sbaindia integration/failsafe tests are typicaly done using an in-memory h2 database.
if h2 is not an option take a look at https://www.testcontainers.org, which can be embeded in unit tests.