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I am following this tutorial: https://docs.docker.com/get-started/02_our_app/
When I updated my app.js file as mentioned in the tutorial (it’s just a label change) then rebuilt and ran my image, Docker successfully runs the app but when I access localhost:3000 it gives me an error. The app was working fine before but now even if I download a fresh copy of the sample project and load it and follow the instruction from the start, accessing localhost:3000 is not showing me the app.
The error I get is this:
This page isn’t working
localhost didn’t send any data.
ERR_EMPTY_RESPONSE
Any hints here on what went wrong? And how can I fix it?
Additional information:
I am using macOS with an m1 chip.
Here is my Docker file code:
# syntax=docker/dockerfile:1
FROM node:12-alpine
RUN apk add --no-cache python g++ make
WORKDIR /app
COPY . .
RUN yarn install --production
CMD ["node", "src/index.js"]
here is the command I run to build and run my Docker:
docker build -t getting-started .
docker run -p 3000:3000 getting-started
This is the log of Docker App when I click on the running container:
/docker-entrypoint.sh: /docker-entrypoint.d/ is not empty, will attempt to perform configuration
/docker-entrypoint.sh: Looking for shell scripts in /docker-entrypoint.d/
/docker-entrypoint.sh: Launching /docker-entrypoint.d/10-listen-on-ipv6-by-default.sh
10-listen-on-ipv6-by-default.sh: info: Getting the checksum of /etc/nginx/conf.d/default.conf
10-listen-on-ipv6-by-default.sh: info: Enabled listen on IPv6 in /etc/nginx/conf.d/default.conf
/docker-entrypoint.sh: Launching /docker-entrypoint.d/20-envsubst-on-templates.sh
/docker-entrypoint.sh: Launching /docker-entrypoint.d/30-tune-worker-processes.sh
/docker-entrypoint.sh: Configuration complete; ready for start up
2021/08/13 09:26:50 [notice] 1#1: using the "epoll" event method
2021/08/13 09:26:50 [notice] 1#1: nginx/1.21.1
2021/08/13 09:26:50 [notice] 1#1: built by gcc 10.3.1 20210424 (Alpine 10.3.1_git20210424)
2021/08/13 09:26:50 [notice] 1#1: OS: Linux 5.10.25-linuxkit
2021/08/13 09:26:50 [notice] 1#1: getrlimit(RLIMIT_NOFILE): 1048576:1048576
2021/08/13 09:26:50 [notice] 1#1: start worker processes
2021/08/13 09:26:50 [notice] 1#1: start worker process 33
2021/08/13 09:26:50 [notice] 1#1: start worker process 34
2021/08/13 09:26:50 [notice] 1#1: start worker process 35
2021/08/13 09:26:50 [notice] 1#1: start worker process 36
Everything seems to be working except the localhost which was working fine until I modified the text and rebuilt the image and run it.
I have also placed the dockerfile in the correct location and have not modified any other file.
3
Answers
You can check few things to get started again with :
run command : docker ps -a
This will give you all the containers running/stopped on the system. It will also list out ports being used , make sure only container uses the port you mapped while in running state or else it will give error.
stop the containers by command : docker stop
Container SHA value will be hex code diplayed in the first column when you run docker ps -a.
Check the location of docker file as they have explicitly asked to put the file in app folder and also one more docker file is already present in getting started project folder so make sure you have not overwritten that file.
I checked and performed the task it runs perfectly fine for me.
I got the same issue, I fixed it by putting the dockerfile in the
/appfolderThe github repo I cloned had it on the upper level and caused the issue.
I had the same issue. You can check your docker app and see if you can click on the 3000:3000 Port if the container is running. For some reaseon I have to click that to see the page.
If not you mightve opened up the wrong app folder in vs code. In my case I had opened vs code to the outer unzipped app folder that contained the other app folder. To fix it I opened the inner /app folder.