I have a python script which I use docker to run by creating a docker image inside a docker container. This is my docker file:
FROM python:3.6
RUN pip install tweepy
RUN pip install pymongo
RUN pip install asyncio
EXPOSE 32771
ADD hash_cat.txt /
ADD tweepy_twitter_stream_v0.6.py /
CMD [ "python", "./tweepy_twitter_stream_v0.6.py" ]
The script reads from hash_cat.txt text file and execute some stuff based on its content.
I want to access hash_cat.txt regularly and change its content.
The problem is:
when I run the image to access its bash and edit the hash_cat.txt and save it , it creates a new container for the image with the hash_cat.txt file without saving the changes I had made to hash_cat.txt.
This is how I run the image shell to edit hash_cat.txt content:
docker run -it python_script bin/bash
Where python_script is the image name.
Then I run
apt-get update
apt-get install vim
to use vim to edit hash_cat.txt content.
After I edited the file and typed :wq to save and exit.
I run the image again using
docker run python_script
My question is: Is it possible to run the image and access it regularly and change hash_cat.txt content without creating a new container every time.
Hope you understood my problem. Any help would be appreciated.
Every time you use docker run there will be a new container, use docker exec -it container_name /bin/bash to visit already existed container please.
Or you had to use volume, and put this file in volume.
So here is a very cool Docker file.
To run it, I do:
wget https://cran.r-project.org/src/contrib/FastRCS_0.0.7.tar.gz
tar -xvzf FastRCS_0.0.7.tar.gz
docker run --rm -ti -v $(pwd):/mnt rocker/r-devel-ubsan-clang check.r --setwd /mnt -a --install-deps FastRCS_0.0.7.tar.gz
But now suppose I want to save this DockerFile and run the saved version from the current directory (i.e. not just the one on github).
How can I do this?
The idea is that I need to customize this DockerFile a bit and run the customized version.
Sounds like you want to download the raw file from https://raw.githubusercontent.com/rocker-org/r-devel-san-clang/master/Dockerfile
and save it into a file named Dockerfile
Then you could edit the file to make your changes, and then just build your image with docker build . when you are in the Dockerfile directory
This is a basic Docker usage question--look into docker commit.
You may want to study one of the many fine Docker tutorials out there.
I've been reading through the Docker documentation and can't seem to work out if its possible to create a custom command/directive. Basically I need to make an HTTP request to external service to retrieve some assets that need to be included within my container. Rather than referencing them using Volumes I want to effectively inject them into the container during the build process, a bit like dependancy injection.
Assuming you are referring to download some files using http (HTTP GET) as one of the example in the question. You can try this.
RUN wget https://wordpress.org/plugins/about/readme.txt
or
RUN curl https://wordpress.org/plugins/about/readme.txt
The example Dockerfile with download shell script
PROJ-DIR
- files
- test.sh
- Dockerfile
files/test.sh
#!/bin/sh
wget https://wordpress.org/plugins/about/readme.txt
Dockerfile
FROM centos:latest
COPY files/test.sh /opt/
RUN chmod u+x /opt/test.sh
RUN rpm --import /etc/pki/rpm-gpg/RPM-GPG-KEY*
RUN yes | yum install wget
RUN /opt/test.sh
RUN rm /opt/test.sh
Build the image
docker build -t test_img .
I use boot2docker and want to build a simple docker image with the Dockerfile:
# Pull base image.
FROM elasticsearch
# Install Marvel plugin
RUN \
&& export ES_HOME=/usr/share/elasticsearch \
&& cd $ES_HOME \
&& bin/plugin -u file:///c/Users/buliov1/dev/elastic/plugins/marvel-latest.zip -i elasticsearch/marvel/latest
The path /c/Users/buliov1/dev/elastic/plugins/marvel-latest.zip is present and accessible on the machine where I build the dockerfile .
The problem is that inside the build i get
Failed: FileNotFoundException[/c/Users/buliov1/dev/elastic/plugins/marvel-latest.zip (No such file or directory)].
I searched through the documentation and the only solution I see is to use ADD/COPY and copy first the file inside the image and then run the command that uses the file.
I don't know how exactly docker build works but , is there a way to build it without copying the file first?
A docker build process is running inside Docker containers and has no access to the host filesystem. The only way to get files into the build environment is through the use of the ADD or COPY mechanism (or by fetching them over the network using, e.g., curl or wget or something).
I am using windows and have boot2docker installed. I've downloaded images from docker hub and run basic commands. BUT
How do I take an existing application sitting on my local machine (lets just say it has one file index.php, for simplicity). How do I take that and put it into a docker image and run it?
Imagine you have the following existing python2 application "hello.py" with the following content:
print "hello"
You have to do the following things to dockerize this application:
Create a folder where you'd like to store your Dockerfile in.
Create a file named "Dockerfile"
The Dockerfile consists of several parts which you have to define as described below:
Like a VM, an image has an operating system. In this example, I use ubuntu 16.04. Thus, the first part of the Dockerfile is:
FROM ubuntu:16.04
Imagine you have a fresh Ubuntu - VM, now you have to install some things to get your application working, right? This is done by the next part of the Dockerfile:
RUN apt-get update && \
apt-get upgrade -y && \
apt-get install -y python
For Docker, you have to create a working directory now in the image. The commands that you want to execute later on to start your application will search for files (like in our case the python file) in this directory. Thus, the next part of the Dockerfile creates a directory and defines this as the working directory:
RUN mkdir -p /usr/src/app
WORKDIR /usr/src/app
As a next step, you copy the content of the folder where the Dockerfile is stored in to the image. In our example, the hello.py file is copied to the directory we created in the step above.
COPY . /usr/src/app
Finally, the following line executes the command "python hello.py" in your image:
CMD [ "python", "hello.py" ]
The complete Dockerfile looks like this:
FROM ubuntu:16.04
RUN apt-get update && \
apt-get upgrade -y && \
apt-get install -y python
RUN mkdir -p /usr/src/app
WORKDIR /usr/src/app
COPY . /usr/src/app
CMD [ "python", "hello.py" ]
Save the file and build the image by typing in the terminal:
$ docker build -t hello .
This will take some time. Afterwards, check if the image "hello" how we called it in the last line has been built successfully:
$ docker images
Run the image:
docker run hello
The output shout be "hello" in the terminal.
This is a first start. When you use Docker for web applications, you have to configure ports etc.
Your index.php is not really an application. The application is your Apache or nginx or even PHP's own server.
Because Docker uses features not available in the Windows core, you are running it inside an actual virtual machine. The only purpose for that would be training or preparing images for your real server environment.
There are two main concepts you need to understand for Docker: Images and Containers.
An image is a template composed of layers. Each layer contains only the differences between the previous layer and some offline system information. Each layer is fact an image. You should always make your image from an existing base, using the FROM directive in the Dockerfile (Reference docs at time of edit. Jan Vladimir Mostert's link is now a 404).
A container is an instance of an image, that has run or is currently running. When creating a container (a.k.a. running an image), you can map an internal directory from it to the outside. If there are files in both locations, the external directory override the one inside the image, but those files are not lost. To recover them you can commit a container to an image (preferably after stopping it), then launch a new container from the new image, without mapping that directory.
You'll need to build a docker image first, using a dockerFile, you'd probably setup apache on it, tell the dockerFile to copy your index.php file into your apache and expose a port.
See http://docs.docker.com/reference/builder/
See my other question for an example of a docker file:
Switching users inside Docker image to a non-root user (this is for copying over a .war file into tomcat, similar to copying a .php file into apache)
First off, you need to choose a platform to run your application (for instance, Ubuntu). Then install all the system tools/libraries necessary to run your application. This can be achieved by Dockerfile. Then, push Dockerfile and app to git or Bitbucket. Later, you can auto-build in the docker hub from github or Bitbucket. The later part of this tutorial here has more on that. If you know the basics just fast forward it to 50:00.