Spring Boot with MongoDB on Docker

Question

In these days, I am trying to deploy my Spring Boot OAuth2 project. It has 3 different modules.(Authentication Server, Resource Server and Front-end) Authentication and Resource servers have own *.yml file for configurations such as mongodb name-port, server profile-ip etc. What I am trying to do exactly? I want to deploy spring boot application on docker but i dont want to put my database(mongodb) on docker as a container. I am not sure this structure is possible or not ? Because When i run my mongodb on my local(localhost:27017) after that try to deploy spring boot application on local docker as a container, i am getting Timeout exception for MongoDB. The application couldnt connect to external mongoDB(non docker container).

What should I do? Should I run mongodb on docker? I tried it also, Mongo runs successfully but still spring container couldnt run and connect to mongo. I tried to run another spring boot app without mongodb, it is working successfully and i made request from browser by ip&port, i got response from application as i expected.

*** MONGO URL ****
mongodb://127.0.0.1:27017/db-localhost

**** Authentication server .yml file   ****
server:
    port: 9080
    contextPath: /auth-service
    tomcat:
          access_log_enabled: true
          basedir: target/tomcat
security:
    basic:
        enabled: false
spring:
    profiles:
        active: development
    thymeleaf:
        cache: false
mongo:
    db:
      server: 127.0.0.1
      port: 27017
logging:
 level:
  org.springframework.security: DEBUG

---

spring:
  profiles: development
  data:
    mongodb:
      database: db-localhost

---

spring:
  profiles: production
  data:
    mongodb:
      database: db-prod

---


***** DOCKER FILE *******
FROM java:8
VOLUME /tmp
ADD auth-server-1.0-SNAPSHOT.jar app.jar
EXPOSE 9080
RUN bash -c 'touch /app.jar'
ENTRYPOINT ["java","-Djava.security.egd=file:/dev/./urandom","-jar","/app.jar"]


**** DOCKER COMMAND *******
docker run -it -P --name authserver authserver

Answer 1

Question: What should I do?

At least for developing purposes I would recommend to also use docker for your mongodb instance. I had a similar setup with RabbitMQ in addition and it solved a lot of problems when I used docker for those as well. Using docker-compose to set everything up makes it even easier. Later you can still specify which mongodb instance you want to use through your spring properties.

Problem: I tried it also, Mongo runs successfully but still spring container couldnt run and connect to mongo

The problem is probably because you have not set up any networks or hostnames for you services. Your spring application can not resolve the hostname of your mongo server, since you specified 127.0.0.1 for your mongodb server in your properties.

I would recommend using docker for your mongodb and use a docker-compose.yml file like this to set everything up:

version: '3.7'
services:
  resource-server:
    image: demo/resource-server:latest
    container_name: resource-server
    depends_on:
      - mongodb-example
    networks:
      - your-network
    ports:
      - 8080:8080

  auth-server:
    image: demo/auth-server:latest
    container_name: auth-server
    depends_on:
      - mongodb-example
    networks:
      - your-network
    ports:
      - 8081:8080

  mongodb-example:
    image: mongo:latest
    container_name: mongo-example
    hostname: mongo-example
    networks:
      - your-network
    ports:
      - 27017:27017

networks:
  your-network:
    name: network-name

Of course you then need to adapt your property file or specify environment variables through your docker-compose.yml file.

Answer 2

The issue with your configuration is referencing the mongodb from inside of the authservice on 127.0.0.1 which is the loopback adapter inside of the authservice container. So you tell your spring application that mongodb is running in the same container as the authservice spring application, which is not the case.

Either you are running your database as an own container (which requires to handle the data volumes correctly) and referencing it using the container name as hostname (via link) or you need to reference the externally running mongodb instance with the correct address. This would be the ip address of the machine running the docker daemon (I assume for your local environment something like 192.168.0.xxx).