Singularity container with stringr fails only locally with 'libicui18n.so.66: cannot open shared object file: No such file or directory'

Question

I enjoy using the Singularity container software, as well as the R package 'stringr' to work with strings.

What I fail to understand is why a Singularity container fails locally (i.e. on my Ubuntu 20.04 computer), yet passes remotely (i.e. on GitHub Actions), when both containers are built at approximately the same time.

Here I run a simple script ([1], see below) that uses stringr:

singularity run --bind $PWD/scripts/ stringr.sif scripts/demo_container.R

(I can remove --bind $PWD/scripts/, but I want to have exactly the same call here as on GitHub Actions)

The error I get is:

'stringr.sif' running with arguments 'scripts/demo_container.R'
Error: package or namespace load failed for ‘stringr’ in dyn.load(file, DLLpath = DLLpath, ...):
 unable to load shared object '/home/richel/R/x86_64-pc-linux-gnu-library/4.1/stringi/libs/stringi.so':
  libicui18n.so.66: cannot open shared object file: No such file or directory
Execution halted

On GitHub Actions, however, this exact call passes without problems (from this GitHub Actions log):

'stringr.sif' running with arguments 'scripts/demo_container.R'
Hello world

The Singularity script is very simple, it only installs and updates apt, then installs the stringr package ([2], see below).

I understand that this is a shared objects problem, there are some workaround that fail in this context:

• sudo apt install libicu-dev: ICU is the library that stringr uses
• uninstall stringr and install it again, forcing a recompilation of the shared object, from this GitHub Issue comment

How can it be my Singularity container fails locally, yet passes on GitHub Actions? How can I fix this, so that the container works in both environments?

A non-fix is to use rocker/tidyverse as a base, which I can get to work successfully, as the question is more about why this stringr setup fails.

Thanks and cheers, Richel Bilderbeek

[1] demo_container.R

library(stringr)
message(stringr::str_trim("   Hello world   "))

[2] Singularity

Bootstrap: docker
From: r-base

%post
    sed -i 's/$/ universe/' /etc/apt/sources.list
    apt-get update
    apt-get clean
    Rscript -e 'install.packages("stringr")'

%runscript
echo "'stringr.sif' running with arguments '$@'"
Rscript "$@"

Answer 1

If you look at the error message, you'll see that the library that cannot be loaded is in your HOME on the host OS: /home/richel/R/x86_64-pc-linux-gnu-library/4.1/stringi/libs/stringi.so

This suggests that the R being used is one you have locally installed on the host and not the one installed in the image. Since singularity processes inherit the full host environment by default, I'd guess you've modified your $PATH and that's clobbering the value set inside the container. Since the environment on the CI / actions server is clean, it is able to run successfully.

I strongly recommend always using the -e/--cleanenv parameters to ensure that the environment inside the singularity container is the same anywhere it is run.