I have a container that uses a volume in its entrypoint. for example
CMD bash /some/volume/bash_script.sh
I moved this to compose but it only works if my compose points to a Dockerfile in the build section if I try to write the same line in the command section is not acting as I expect and throws file not found error.
I also tried to use docker-compose run <specific service> bash /some/volume/bash_script.sh which gave me the same error.
The question is - Why dont I have this volume at the time that the docker-compose 'command' is executed? Is there anyway to make this work/ override the CMD in my dockerfile?
EDIT:
I'll show specifically how I do this in my files:
docker-compose:
version: '3'
services:
base:
build:
context: ..
dockerfile: BaseDockerfile
volumes:
code:/volumes/code/
my_service:
volumes:
code:/volumes/code/
container_name: my_service
image: my_service_image
ports:
- 1337:1337
build:
context: ..
dockerfile: Dockerfile
volumes:
code:
BaseDockerfile:
FROM python:3.6-slim
WORKDIR /volumes/code/
COPY code.py code.py
CMD tail -f /dev/null
Dockerfile:
FROM python:3.6-slim
RUN apt-get update && apt-get install -y redis-server \
alien \
unixodbc
WORKDIR /volumes/code/
CMD python code.py;
This works.
But if I try to add to docker-compose.yml this line:
command: python code.py
Then this file doesnt exist at the command time. I was expecting this to behave the same as the CMD command
Hmm, nice point!
command: python code.py is not exactly the same as CMD python code.py;!
Since the first one is interpreted as a shell-form command, where the latter is interpreted as an exec-form command.
The problem is about the differences in these two types of CMDs. (i.e. CMD ["something"] vs CMD "something").
For more info about these two, see here.
But, you may still be thinking of what's wrong with your example?
In your case, based on the specification of YAML format, python code.py in the command: python code.py will be interpreted as a single string value, not an array!
On the other hand, as you've probably guessed, python code.py; in the above-mentioned Dockerfile is interpreted as an array, which provides an exec-form command.
The (partial) answer is that the error that was thrown was not at all what the problem was.
Running the following command: bash -c 'python code.py' worked fine. I still cant explain why there was a difference between CMD in Dockerfile and docker-compose "command" oprtion. but this solved it for me
I found out this will work:
command: python ./code.py
Related
I have script: docker run -it -p 4000:4000 bitgosdk/express:latest --disablessl -e test
how to put this command to dockerfile with arguments?
FROM bitgosdk/express:latest
EXPOSE 4000
???
Gone through your Dockerfile contents.
The command running inside container is:
/ # ps -ef | more
PID USER TIME COMMAND
1 root 0:00 /sbin/tini -- /usr/local/bin/node /var/bitgo-express/bin/bitgo-express --disablessl -e test
The command is so because the entrypoint set in the Dockerfile is ENTRYPOINT ["/sbin/tini", "--", "/usr/local/bin/node", "/var/bitgo-express/bin/bitgo-express"] and the arguments --disablessl -e test are the one provided while running docker run command.
The --disablessl -e test arguments can be set inside your Dockerfile using CMD:
CMD ["--disablessl", "-e","test"]
New Dockerfile:
FROM bitgosdk/express:latest
EXPOSE 4000
CMD ["--disablessl", "-e","test"]
Refer this to know the difference between entrypoint and cmd.
You don't.
This is what docker-compose is used for.
i.e. create a docker-compose.yml with contents like this:
version: "3.8"
services:
test:
image: bitgodsdk/express:latest
command: --disablessl -e test
ports:
- "4000:4000"
and then execute the following in a terminal to access the interactive terminal for the service named test.
docker-compose run test
Even if #mchawre's answer seems to directly answer OP's question "syntactically speaking" (as a Dockerfile was asked), a docker-compose.yml is definitely the way to go to make a docker run command, as custom as it might be, reproducible in a declarative way (YAML file).
Just to complement #ChrisBecke's answer, note that the writing of this YAML file can be automated. See e.g., the FOSS (under MIT license) https://github.com/magicmark/composerize
FTR, the snippet below was automatically generated from the following docker run command, using the accompanying webapp https://composerize.com/:
docker run -it -p 4000:4000 bitgosdk/express:latest
version: '3.3'
services:
express:
ports:
- '4000:4000'
image: 'bitgosdk/express:latest'
I omitted the CMD arguments --disablessl -e test on-purpose, as composerize does not seem to support these extra arguments. This may sound like a bug (and FTR a related issue is opened), but meanwhile it might just be viewed as a feature, in line of #DavidMaze's comment…
I found the following guideline to set up a Jupyter notebook locally:
version: "3"
services:
datascience-notebook:
image: jupyter/datascience-notebook
volumes:
- /Absolute/Path/To/Where/Your/Notebook/Files/Will/Be/Saved:/home/jovyan/work
ports:
- 8888:8888
container_name: datascience-notebook-container
Now I want to add one more library to this image. The command is conda install -c conda-forge fbprophet It's explained here how to achieve it with a .Dockerfile. However, how can I achieve that using compose?
You can override entrypoint in docker compose file, as this will override the entrypoint command in any ancestor of the docker file, you need to make sure you also call that entry point command.
The entrypoint of jupyter/base-notebook (root of docker image you are using) is
ENTRYPOINT ["tini", "-g", "--"]
Adding following line in the compose file may do what you wanted to do (I haven't tried it)
entrypoint: [ "conda", "install", "-c", "conda-forge", "fbprophet", "&&", "tini", "-g", "--"]
But downside of it is that this command will run every time container is started slowing down container start up time. So recommended way is the solution you mentioned in you question
I am trying to learn how to containerize my flask api with docker. I am very new to docker, but from my understanding, I was able to build/update it. When I navigate to my route I get site can't be reached.
Any help would be greatly appreciated. Thank you.
Here is my yml file:
version: "3.6"
services:
users:
build:
context: ./services/users
dockerfile: Dockerfile-dev
volumes:
- "./services/users:/usr/src/app"
ports:
- 5001:5000
environment:
- FLASK_APP=project/__init__.py
- FLASK_ENV=development
- APP_SETTINGS=project.config.DevelopmentConfig
here is my dockerfile:
FROM python:3.6.5-alpine
WORKDIR /usr/src/app
COPY ./requirements.txt /usr/src/app/requirements.txt
RUN pip install -r requirements.txt
COPY . /usr/src/app
CMD python manage.py -h 0.0.0.0
and here is my powershell command and output:
docker-compose -f docker-compose-dev.yml up -d --build
upon further diagnosis I found this from the ps command
I however cannot find in docker documentation what state of exit 2 means. Unless that is bash for misuse of shell builtin: http://www.tldp.org/LDP/abs/html/exitcodes.html. In that case I really don't know my problem and would appreciate any help!
Edit 3:
upon reading some github threads removing the -d flag from my command showed more information but it is still cryptic if anyone has an explanation for it:
I guess new flask versions doesn't support -h anymore, try with --host -
Change CMD statement in Dockerfile to -
CMD python manage.py runserver --host 0.0.0.0
Ref - https://flask-script.readthedocs.io/en/latest/
I have the following entryfile
FROM <image-of-nodejs>
COPY docker/node/entry.sh /var/entries/entry.sh
RUN apt-get update
RUN apt-get install ant -y
CMD ["/var/entries/entry.sh"]
the image is used by a docker-compose file:
version: "3.3"
services:
my_node:
build:
context: ./
dockerfile: docker/node/Dockerfile-build-dev
volumes:
- type: bind
source: ./
target: /var/proj
and the entry.sh file is the following:
#!/bin/bash
export QNAMAKER_SUB_KEY=b13615t
If I then start the image and I enter the docker, I won't find my env variable set:
docker-compose up --force-recreate -d
docker-compose run my_node bash
root#9c081bedde65:/# echo ${QNAMAKER_SUB_KEY}
<empty>
I would prefer to set my variables throug my script in place of the ENV Dockerfile command. What's wrong?
There are a couple of things going on here.
First, docker-compose run doesn't run a command inside the container you started with docker-compose up. It starts a new container to run a one-off command. You probably want docker-compose exec.
The reason you don't see the variable when using docker-compose run is that you are overriding your CMD by providing a new command (bash) on the docker-compose run command line.
You could consider:
Using ENV statements in your Dockerfile.
Using the environment key in your docker-compose.yml
The former will embed the information into your image, while the latter would mean that the variable would be unset if you didn't explicitly set it in your docker-compose.yaml file (or using -e on the docker run command line).
You may be able to accomplish your goal using an ENTRYPOINT script and setting the value there, but that won't impact the environment visible to you when using docker exec (or docker-compose exec).
I have just started learning Docker, and run into this issue which don't know how to go abound.
My Dockerfile looks like this:
FROM node:7.0.0
WORKDIR /app
COPY app /app
COPY hermes-entry /usr/local/bin
RUN chmod +x /usr/local/bin/hermes-entry
COPY entry.d /entry.d
RUN npm install
RUN npm install -g gulp
RUN npm install gulp
RUN gulp
My docker-compose.yml looks like this:
version: '2'
services:
hermes:
build: .
container_name: hermes
volumes:
- ./app:/app
ports:
- "4000:4000"
entrypoint: /bin/bash
links:
- postgres
depends_on:
- postgres
tty: true
postgres:
image: postgres
container_name: postgres
volumes:
- ~/.docker-volumes/hermes/postgresql/data:/var/lib/postgresql/data
environment:
POSTGRES_PASSWORD: password
ports:
- "2345:5432"
After starting the containers up with:
docker-compose up -d
I tried running a simple bash cmd:
docker-compose run hermes ls
And I got this error:
/bin/ls cannot execute binary file
Any idea on what I am doing wrong?
The entrypoint to your container is bash. By default bash expects a shell script as its first argument, but /bin/ls is a binary, as the error says. If you want to run /bin/ls you need to use -c /bin/ls as your command. -c tells bash that the rest of the arguments are a command line rather than the path of a script, and the command line happens to be a request to run /bin/ls.
You can't run Gulp and Node at the same time in one container. Containers should always have one process each.
If you just want node to serve files, remove your entrypoint from the hermes service.
You can add another service to run gulp, if you are having it run tests, you'd have to map the same volume and add a command: ["gulp"]
And you'd need to remove RUN gulp from your dockerfile (unless you are using it to build your node files)
then run docker-compose up