shinyapps.io publish error, .NET mono not installed on server?

[bnmoore]

I was trying to publish a shiny app on shinyapps.io that uses the "rawrr" package (from Bioconductor). This package uses .NET to access mass spec raw data files. The error message is below. Any suggestions on how to get around this? I suspect this just might not be possible.

Error: package or namespace load failed for ‘rawrr’:
.onLoad failed in loadNamespace() for 'rawrr', details:
call: fun(libname, pkgname)
error: The cross platform, open source .NET framework (mono) is not available.
Consider to install 'apt-get install mono-runtime' on Linux
or download/install from https://www.mono-project.com/.

[jimbrig2011]

You will need a way to install .NET onto the server as an external system requirement. Can be accomplished by:

1. Creating a package with the proper sysreqs to install alongside your package and try to install the package on the server.

2. Use docker (easy way), but not sure if compatible with shinyapps.io or not.

Otherwise only other option is to separate the .NET dependencies with rawrr into a separate API to call outside the scope of the shinyapps.io server as a sidecar/microservice.

[jimbrig2011]

Also, you can try adding the package to the system-requirements repo on GitHub: rstudio/shinyapps-package-dependencies

---

Source: https://docs.posit.co/shinyapps.io/appendix.html#default-system-packages:

When you make a new deployment to shinyapps.io, system software from Ubuntu 22.04 (Jammy) is added to the environment where your application runs. This is true for all new deployments, including to applications with existing deployments that run on older versions of Ubuntu.

The following are the default system packages that are present before any additional R packages are installed. Note, the version of R will differ based upon what you are using locally. If your application happens to use an R package that requires a system library that is not included on this list, please let us know by filing an issue, or a pull request, at shinyapps-package-dependencies.

See: 10.2 Default System Packages (posit.co)

View Head of Currently Supported System Package Dependencies

$ dpkg-query --list
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name                                   Version                                    Architecture Description
+++-======================================-==========================================-============-================================================================================================
ii  adduser                                3.118ubuntu5                               all          add and remove users and groups
ii  adwaita-icon-theme                     41.0-1ubuntu1                              all          default icon theme of GNOME (small subset)
ii  apt                                    2.4.10                                     amd64        commandline package manager
ii  asymptote                              2.78+ds-2                                  amd64        script-based vector graphics language inspired by MetaPost

..... limited due to character restrictions
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