My container of play/scala application starts at [info] p.c.s.AkkaHttpServer - Listening for HTTP on /0.0.0.0:9000. But I am unable to connect to it from the browser. I am running the container on my windows machine after having build the image using Docker for Windows
The Dockerfile is
FROM openjdk:8
WORKDIR deploy
COPY target/universal/myapp-1.0.zip .
COPY conf/logback_dev.xml ./logback.xml
COPY conf/application_dev.conf ./application.conf
RUN unzip myapp-1.0.zip
RUN chmod +x myapp-1.0/bin/myapp
EXPOSE 9000
ENTRYPOINT myapp-1.0/bin/myapp -Dplay.http.secret.key=changemeplease -Dlogger.file=/deploy/logback.xml -Dconfig.file=/deploy/application.conf
I am starting the container as docker run myApp -p 9000:9000 -network="host" and also tried docker run myApp -p 9000:9000 -network="host"
UPDATE
this is interesting. If I specify image name before port then the application isn't reachable
docker run myApp -p 9000:9000
In docker container ps -a, I see (no mapping of localhost:9000 to 9000)
C:\Users\manuc>docker container ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
4d16547cd96d myApp "/bin/sh -c 'myApp…" 10 seconds ago Up 9 seconds 9000/tcp, 9042/tcp ecstatic_bell
but if I specify port before image name, then the application is reachable
docker run -p 9000:9000 myApp
In docker container ps -a, I see mapping of localhost:9000 -> 9000
C:\Users\manuc>docker container ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
24b571cc0057 myApp "/bin/sh -c 'MyApp…" 39 seconds ago Up 38 seconds 0.0.0.0:9000->9000/tcp, 9042/tcp silly_yalow
Things to do when your container is not behaving like you want:
Check if your application is running in your computer.
After you run your container, check if it is healthy with docker ps. If it is not healthy, the problem is usually in your application.
Ensure it is running without errors, check logs with docker logs <container-id>. If logs are ok, problem is usually in the container network configuration.
Ensure you can access your application with docker exec -it <container-id> bash. And try to access port with curl or wget. If it is not reachable problem can be in iptables, firewall, or your application.
If you can ensure all the steps above working as expected. The problem is in docker network configuration.
Docker network host only works in linux, not mac and windows. You can run container with docker run -p 9000:9000 myapp. Checkout documentation: https://docs.docker.com/network/host/#:~:text=The%20host%20networking%20driver%20only,the%20docker%20service%20create%20command.
General form of the docker run command is docker run [OPTIONS] IMAGE[:TAG|@DIGEST] [COMMAND] [ARG...] as you can see in documentation. You need to specify port options before image name.