Can't dockerize spring micro-services multi module app

Question

I'm building a application with JAVA 11, maven, spring. It has a root pom to organize all child modules as seen on: https://github.com/erickmob/spring-petclinic-microservices

Here's the project structure:

I've tried to create on the root project this docker-compose.yml:

  version: '2'
    services:
      config-server:
        build:
          context: ./config-server
          dockerfile: Dockerfile
        image: config-server
        container_name: config-server
        mem_limit: 512M
        ports:
          - 8888:8888

And in the config-server this dockerfile:

FROM maven:3.6.3-adoptopenjdk-11 as build

WORKDIR /usr/src/config-server/
COPY . /usr/src/config-server/

RUN mvn clean package

FROM adoptopenjdk/openjdk11:alpine-jre

RUN addgroup -S spring && adduser -S spring -G spring

RUN mkdir -p /files &&  \
    chown -R spring:spring /files

USER spring:spring


VOLUME /files

WORKDIR /app

COPY --from=build /usr/src/config-server/target/config-server-0.0.1-SNAPSHOT.jar /app/app.jar

EXPOSE 8888

ENTRYPOINT ["java", "-jar", "app.jar"]

But it keeps given me this output error:

Building config-server
Step 1/13 : FROM maven:3.6.3-adoptopenjdk-11 as build
 ---> 739e519745cd
Step 2/13 : WORKDIR /usr/src/config-server/
 ---> Using cache
 ---> da21e56bb1f0
Step 3/13 : COPY . /usr/src/config-server/
 ---> Using cache
 ---> 08a5585f625f
Step 4/13 : RUN mvn clean package
 ---> Running in ed76a0ae6b41
[INFO] Scanning for projects...
[ERROR] [ERROR] Some problems were encountered while processing the POMs:
[FATAL] Non-resolvable parent POM for com.erickmob.petclinic:config-server:1.0.0-SNAPSHOT: Could not find artifact com.erickmob.pet-clinic:pet-clinic:pom:1.0-SNAPSHOT and 'parent.relativePath' points at wrong local POM @ line 5, column 13
 @ 
[ERROR] The build could not read 1 project -> [Help 1]
[ERROR]   
[ERROR]   The project com.erickmob.petclinic:config-server:1.0.0-SNAPSHOT (/usr/src/config-server/pom.xml) has 1 error
[ERROR]     Non-resolvable parent POM for com.erickmob.petclinic:config-server:1.0.0-SNAPSHOT: Could not find artifact com.erickmob.pet-clinic:pet-clinic:pom:1.0-SNAPSHOT and 'parent.relativePath' points at wrong local POM @ line 5, column 13 -> [Help 2]
[ERROR] 
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR] 
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/ProjectBuildingException
[ERROR] [Help 2] http://cwiki.apache.org/confluence/display/MAVEN/UnresolvableModelException
ERROR: Service 'config-server' failed to build: The command '/bin/sh -c mvn clean package' returned a non-zero code: 1

If I make a mvn clean install on root folder or config-server folder, everything is ok, but when I try to run docker-compose build it gives me error saying that cannot found the parent pom.

Answer 1

IIUC,

docker-compose.yml

version: "2"
services:
  config-server:
    build:
      context: ./
      dockerfile: Dockerfile
    image: config-server
    container_name: config-server
    mem_limit: 512M
    ports:
      - 8888:8888

Dockerfile

FROM maven:3.6.3-adoptopenjdk-11 as build

COPY . /usr/src/

WORKDIR /usr/src/


RUN mvn clean package

FROM adoptopenjdk/openjdk11:alpine-jre

RUN addgroup -S spring && adduser -S spring -G spring

RUN mkdir -p /files &&  \
        chown -R spring:spring /files

USER spring:spring


VOLUME /files

WORKDIR /app

COPY --from=build /usr/src/config-server/target/config-server-0.0.1-SNAPSHOT.jar /app/app.jar

EXPOSE 8888

ENTRYPOINT ["java", "-jar", "app.jar"]

run the following command docker-compose up -d logs:

root@ubuntu:/home/sathya/Desktop/stackoverflo/docker/spring-boot/spring-petclinic-microservices# docker-compose up -d
Building config-server
Step 1/13 : FROM maven:3.6.3-adoptopenjdk-11 as build
 ---> a4579cf3debf
Step 2/13 : COPY . /usr/src/
 ---> 9841e6033a86
Step 3/13 : WORKDIR /usr/src/
 ---> Running in aa2526d60d42
Removing intermediate container aa2526d60d42
 ---> 6e3b35f66218
Step 4/13 : RUN mvn clean package
 ---> Running in 5b2bac4dcef4
[INFO] Scanning for projects...
Downloading from central: https://repo.maven.apache.org/maven2/org/springframework/boot/spring-boot-starter-parent/2.3.2.RELEASE/spring-boot-starter-parent-2.3.2.RELEASE.pom
Downloaded from central: https://repo.maven.apache.org/maven2/org/springframework/boot/spring-boot-starter-parent/2.3.2.RELEASE/spring-boot-starter-parent-2.3.2.RELEASE.pom (8.6 kB at 2.2 kB/s)
Downloading from central: https://repo.maven.apache.org/maven2/org/springframework/boot/spring-boot-dependencies/2.3.2.RELEASE/spring-boot-dependencies-2.3.2.RELEASE.pom
Downloaded from central: https://repo.maven.apache.org/maven2/org/springframework/boot/spring-boot-dependencies/2.3.2.RELEASE/spring-boot-dependencies-2.3.2.RELEASE.pom (122 kB at 25 kB/s)
Downloading from central: https://repo.maven.apache.org/maven2/com/datastax/oss/java-driver-bom/4.6.1/java-driver-bom-4.6.1.pom
Downloaded from central: https://repo.maven.apache.org/maven2/com/datastax/oss/java-driver-bom/4.6.1/java-driver-bom-4.6.1.pom (3.8 kB at 3.1 kB/s)
Downloading from central: https://repo.maven.apache.org/maven2/io/dropwizard/metrics/metrics-bom/4.1.11/metrics-bom-4.1.11.pom

Answer 2

This is not really Docker, but Maven.

You are building your config-server/ project only (and here is when Docker is in the middle) but the "context" sent to Docker is just what's inside config-server/ and not the entire project. To build config-server/ you need the entire project because you are referring/using a parent POM.