install_packages.R

required_packages <- function(required) {
    if(missing(required)) {
        required <- c(
            # tidyverse
            "tidyverse",
            # Rstudio
            "rmarkdown",
            # W3 packages
            "tinytex", "pander", "kableExtra", "remotes",
            # biometryassist
            "biometryassist"
        )
    }

    if(Sys.info()[['sysname']]!="Linux") {
        oo <- options(install.packages.compile.from.source = "never")
        on.exit(options(oo))
    }

    installed <- rownames(installed.packages())
    notInstalled <- setdiff(required, installed)

    if (length(notInstalled) > 0){

        message("Installing required packages...\n")
        install.packages(notInstalled, quiet = TRUE,
                         Ncpus = getOption("Ncpus", max(parallel::detectCores() - 2, 1)))

        installed <- rownames(installed.packages()) # Update to see what's there now
        missingPackages <- setdiff(required, installed)


        if (length(missingPackages) > 0){
            invisible(sapply(missingPackages,
                             function(x){
                                 warning("\nThe package ", x, " has not installed sucessfully.\n",
                                         "Please copy and paste the code:\n\n\t install.packages('", x,
                                         "')\n\n and try running it again on the console. \n\n
                                 If that fails again, please email the output to biometrytraining@adelaide.edu.au\n")
                             }))
            stop("Installation unsuccessful.")
        }
        else{
            message("All required packages have been installed.\n")
        }
    }
    else {
        message("\nRequired packages are installed.\n")
    }
}