using webshot inside a docker container - r

Question

I try to use webshot (and phantomjs) inside a docker container
please have a look to this minimal Dockerfile
FROM rocker/geospatial
RUN R -e 'webshot::install_phantomjs()'
RUN apt-get update -qq && apt-get install -qy \
ca-certificates \
bzip2 \
curl \
libfontconfig \
--no-install-recommends \
&& curl -SL https://bitbucket.org/ariya/phantomjs/downloads/phantomjs-2.1.1-linux-x86_64.tar.bz2 > phantom.tar.bz2 \
&& bzip2 -d ./phantom.tar.bz2 \
&& tar -xvf ./phantom.tar -C /usr/local/ --strip-components=1 \
&& rm phantom.tar \
&& apt-get -qy remove bzip2 curl \
&& rm -rf /var/lib/apt/lists/*
then
docker build . -t test
docker run -it test bash
and inside R
webshot:::find_phantom() #"/usr/local/bin/phantomjs"
system("ping www.r-project.org") # ok
webshot::webshot("https://www.r-project.org/", "r.png") # nothing happend
Any idea why?
thanks

Answer 1

This is probably because by default, you are at the root of the distribution and you can not write on it.
If I try this:
~$ docker run -it rocker/geospatial bash
~$ R
> webshot::install_phantomjs()
> webshot:::find_phantom()
[1] "/root/bin/phantomjs"
> list.files() # At the root /
> setwd("/home/rstudio/kitematic/") # Go to allowed directory
> webshot::webshot("https://www.r-project.org/", "r.png")
> list.files()
[1] "r.png"