Warning: Error in : pandoc version 2.0.5 or higher is required and was not found (see the help page ?rmarkdown::pandoc_available). [No stack trace available]

[zhanhaopeh]

Hi all,

I've just published my shiny app to an open-source shiny-server. However, my R Markdown scripts are not rendering and I am getting the following error:

Warning: Error in : pandoc version 2.0.5 or higher is required and was not found (see the help page ?rmarkdown::pandoc_available).
  [No stack trace available]

Does anyone know why this is the case? How can I install pandoc via command line on the shiny-server (open source)?

[cderv]

It is seems that you don't have the correct versions of pandoc in your shiny server. You may use some new feature of pandoc that requires pandoc > 2. Currently, standard RStudio production include the 1.19 I think. The preview product (IDE for example) embedded the 2.x.x

You can check on the server the version that should be included with the shiny server install (not sure about the path... but somewhere)

/opt/shiny-server/ext/pandoc/pandoc --version

You may need to update or install a new version for this Rmd of yours. The pandoc executable can be chosen with Sys.getenv("RSTUDIO_PANDOC") if you have several versions

Hope it helps

[zhanhaopeh]

You are absolutely right. May I know how can I upgrade pandoc on my shiny server?

[grrrck]

If you have admin access to the server that shiny server is running on, follow the pandoc installation on Linux instructions to upgrade to the latest version of pandoc.

[zhanhaopeh]

You are absolutely right! I realised that my current version of pandoc is 1.19.2.1. Could you advise me on how I can upgrade the version to something higher than 2.x.x?

[cderv]

You can upgrade following @grrrck advice and link.
I don't if it is possible to install another version on the same server.
If so you can use RSTUDIO_PANDOC environment variable to tell R and Rmarkdown, which version to use for a document. That way, I think having several version is possible.