Dockerfile-kitchen-sink

# A Dockerfile with everything
# From https://gist.github.com/junjaytan/cf40492b726699f62ac7
FROM <image>:<tag>

MAINTAINER <name>

# RUN executes any commands in a new layer on top of the current image and 
# commits the results. The resulting committed image will be used for the 
# next step in the Dockerfile
# 2 forms:
#   RUN <command> (shell form if /bin/sh exists)
#   RUN ["executable", "param1", "param2"] (exec form)
RUN /bin/bash -c 'source $HOME/.bashrc ;\
RUN ["/bin/bash", "-c", "echo hello"]

# CMD provides defaults for an executing container
# 3 forms:
#   CMD ["executable","param1","param2"] (exec form, preferred)
#   CMD ["param1","param2"]
#   CMD command param1 param2 (shell form)
CMD echo "This is a test." | wc -

# LABEL instruction adds metadata to an image
# form: LABEL <key>=<value> <key>=<value> <key>=<value> ...
LABEL "com.example.vendor"="ACME Incorporated"
LABEL com.example.label-with-value="foo"
LABEL version="1.0"
LABEL description="This text illustrates \
that label-values can span multiple lines."

# EXPOSE instruction informs Docker that the container listens on the specified network ports at runtime. 
# EXPOSE does not make the ports of the container accessible to the host. To do that, 
# you must use either the -p flag to publish a range of ports or the -P flag to publish all of the exposed ports
EXPOSE <port> [<port>...]

# ENV instruction sets the environment variable <key> to the value <value>. This value will be 
# in the environment of all “descendent” Dockerfile commands and can be replaced inline in many as well
# forms:  ENV <key> <value>
#         ENV <key>=<value> ...
ENV myName="John Doe" myDog=Rex\ The\ Dog \
    myCat=fluffy
    
# ADD instruction copies new files, directories or remote file URLs from <src> and adds them to the 
# filesystem of the container at the path <dest>
# forms:
#     ADD <src>... <dest>
#     ADD ["<src>",... "<dest>"] (required for paths containing whitespace)
ADD hom* /mydir/        # adds all files starting with "hom"
ADD hom?.txt /mydir/    # ? is replaced with any single character, e.g., "home.txt"

# COPY instruction copies new files or directories from <src> and adds them 
# to the filesystem of the container at the path <dest>.
COPY hom* /mydir/        # adds all files starting with "hom"
COPY hom?.txt /mydir/    # ? is replaced with any single character, e.g., "home.txt"

# ENTRYPOINT allows you to configure a container that will run as an executable.
# 2 forms
#     ENTRYPOINT ["executable", "param1", "param2"] (exec form, preferred)
#     ENTRYPOINT command param1 param2 (shell form)
ENTRYPOINT ["executable", "param1", "param2"]

# VOLUME instruction creates a mount point with the specified name and marks it as 
# holding externally mounted volumes from native host or other containers. The 
# value can be a JSON array, VOLUME ["/var/log/"], or a plain string with multiple arguments, 
# such as VOLUME /var/log or VOLUME /var/log /var/db
VOLUME /myvol

# USER instruction sets the user name or UID to use when running the image and 
# for any RUN, CMD and ENTRYPOINT instructions that follow it in the Dockerfile
USER daemon

# WORKDIR instruction sets the working directory for any RUN, CMD, ENTRYPOINT, COPY and ADD 
# instructions that follow it in the Dockerfile. It can be used multiple times in the one Dockerfile
WORKDIR /a
WORKDIR b
WORKDIR c