About application

Simple backend applicaction that counts number of visits happened to be done by an user. Redis stores the data of the visits made.

ERROR DESCRIPTION

春天电梯应用虽然显示再电,但无法与再电服务器连接,并且其应用也在同一cker网。

error @http://localhost:8080/ -

White label Error  (type=Internal Server Error, status=500).

Error in sprinboot-app container:

Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception 
[Request processing failed: 
org.springframework.data.redis.RedisConnectionFailureException: Unable to connect to Redis] with root cause

Dockerfile:

FROM openjdk:17
WORKDIR /app
COPY target/visitsapplication-0.0.1-SNAPSHOT.jar app.jar
EXPOSE 8080
CMD ["java", "-jar", "app.jar"]

DockerCompose.yml

version:  3 
services:
    redis-server:
    image:  redis 
    ports:
        - "6379:6379"
    springboot-app:
    build: .
    ports:
        - "8080:8080"  

application.properties

server.port=8080
spring.redis.host=redis-server
spring.redis.port=6379

VisitController.java

package com.visitapplication.controller;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.core.ValueOperations;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
@RequestMapping("/")
public class VisitsController {
        @Autowired
        private RedisTemplate<String, String> redisTemplate;

        @GetMapping
        public String getVisits() {
            ValueOperations<String, String> ops = redisTemplate.opsForValue();
            String visits = ops.get("visits");

            if (visits == null) {
                visits = "0";
            }

            ops.set("visits", String.valueOf(Integer.parseInt(visits) + 1));

            return "Number of visits is " + visits;
        }
}

Commands run to check the issues

Command:

 docker-compose logs springboot-app

Output :

java.net.ConnectException: Connection refused.

Command:

docker network inspect visitsapplication_default

Output:

[
    {
        "Name": "visitsapplication_default",
        "Id": "671f39cacd25f8f2c694eebed7515c16dfae3efedc86ae57c567e8ab0567fed2",
        "Created": "2023-12-14T06:06:20.465060571Z",
        "Scope": "local",
        "Driver": "bridge",
        "EnableIPv6": false,
        "IPAM": {
            "Driver": "default",
            "Options": null,
            "Config": [
                {
                    "Subnet": "172.20.0.0/16",
                    "Gateway": "172.20.0.1"
                }
            ]
        },
        "Internal": false,
        "Attachable": false,
        "Ingress": false,
        "ConfigFrom": {
            "Network": ""
        },
        "ConfigOnly": false,
        "Containers": {
            "7437823988de4a68b31f72b423d75bd7172be555b7c77879a5f76eb3cb248d1d": {
                "Name": "visitsapplication-redis-server-1",
                "EndpointID": "c138d3fa863efed0accf193acc4992a382245e160840337554fc76f74e3f914e",
                "MacAddress": "02:42:ac:14:00:03",
                "IPv4Address": "172.20.0.3/16",
                "IPv6Address": ""
            },
            "be2ef8d7f9ed05fb7b98e21473948b7f005fa0fb3b268f03105a98ee5ae79eeb": {
                "Name": "visitsapplication-springboot-app-1",
                "EndpointID": "fa1ee3bccb4097dbe8cfb5388eb471c9836e2a84b21e94fc266d3542e0e81e5a",
                "MacAddress": "02:42:ac:14:00:02",
                "IPv4Address": "172.20.0.2/16",
                "IPv6Address": ""
            }
        },
        "Options": {},
        "Labels": {
            "com.docker.compose.network": "default",
            "com.docker.compose.project": "visitsapplication",
            "com.docker.compose.version": "2.17.3"
        }
    }
]

The Docker network inspection confirms that both visitsapplication-redis-server-1 and visitsapplication-springboot-app-1 containers are on the same Docker network named visitsapplication_default. Therefore, they should be able to communicate with each other using their service names (redis-server and springboot-app, respectively).But that is not the case