R Packages

Global R package dependencies

Files in global/packages declare R packages that are used by one or more apps in a suite. They are read by MDI::install() to discover the R packages to install.

Component R package dependencies

Any app, module, or other component can also declare its need for a specific R package in its module.yml or config.yml file (there is no harm in relisting a package already listed elsewhere - it will only be installed once):

packages: 
   R:  
    - xxx
    - yyy
   Bioconductor: null

Installing vs. attaching

Packages declared in a tool suite are installed but are never attached using the library() function. Thus, you must either:

• call functions in full syntax, e.g., package::function() (preferred)
• call library(package) yourself (discouraged, you could break the framework)

In contrast, packages listed in the ‘mdi-apps-framework’ repository are attached and their functions can be called directly, e.g., Shiny’s observeEvent().