Using httpgd
to display R plots in a Docker container (Linux container) may be easier than the traditional and common method; linking the X11 window system.
See the vignette("a00_installation")
for details on how to install httpgd
on Linux.
You can create a Docker image with httpgd
installed by create a Dockerfile like below.
FROM r-base:latest
# Install httpgd and dependent packages.
RUN apt-get update \
&& apt-get install -y --no-install-recommends \
libfontconfig1-dev \
&& apt-get autoremove -y && apt-get clean -y && rm -rf /var/lib/apt/lists/* \
&& install2.r --error --skipinstalled --ncpu -1 \
httpgd \ && rm -rf /tmp/downloaded_packages
Run the docker build
command from your shell to build a Docker image.
docker build . -f Dockerfile -t httpgd:test
When creating a container with the docker run
command, bind the port to be used by httpgd
with the -p
(--publish
) option.
If you run R in a container with a command like the following, the 8888 port of the container will be bound to the 8888 port of the Docker host.
docker run --rm -it -p 8888:8888 httpgd:test R
Running the following command in the R console will initialize the graphics device and start the server.
::hgd(host = "0.0.0.0", port = 8888) httpgd
Then, copy the displayed link in your browser.
If you want to display the link again, execute the hgd_url()
function as follows.
The hostname can be replaced with any value (e.g. localhost).
::hgd_url(host = "localhost") httpgd
By setting options httpgd.host
and httpgd.port
in the Rprofile, you can omit setting the arguments when starting the httpgd server by hgd()
.
For example, if you create a Dockerfile with the following contents, you can build an image with these options already set in the Rprofile.
FROM r-base:latest
# Install httpgd and dependent packages.
RUN apt-get update \
&& apt-get install -y --no-install-recommends \
libfontconfig1-dev \
&& apt-get autoremove -y && apt-get clean -y && rm -rf /var/lib/apt/lists/* \
&& install2.r --error --skipinstalled --ncpu -1 \
httpgd \
&& rm -rf /tmp/downloaded_packages
# Set default values used in the httpgd::hgd() function.
RUN echo 'options(httpgd.host = "0.0.0.0", httpgd.port = 8888)' >> /etc/R/Rprofile.site
EXPOSE 8888