R/Chart_config.R

In nachocab/clickme: Straight from R to JS: Create interactive visualizations from R

#' @include Chart.R
Chart$methods(

    get_config = function() {
        get_unvalidated_config()
        validate_config()
    },

    get_unvalidated_config = function() {
        internal$config <<- yaml.load_file(internal$file$paths$config_file)
    },

    validate_config = function() {
        validate_required_packages()
        validate_assets()
    },

    validate_required_packages = function() {
        if (!is.null(internal$config$require_packages)){
            missing_packages <- internal$config$require_packages[!is.installed(internal$config$require_packages)]

            if (length(missing_packages) != 0){
                message(separator())
                message(sprintf("The %s template requires the following packages:\n\n%s\nPress Enter to install them automatically or \"c\" to cancel.",
                        internal$file$names$template,
                        paste0(missing_packages, collapse="\n"))
                )
                response <- readline()
                if (tolower(response) == "c"){
                    message(sprintf("Try running: install.packages(%s)",
                        paste0(missing_packages, collapse=",")))
                    capture.output(return())
                } else {
                    install.packages(missing_packages)
                }
                message(separator())
            }

            sapply(internal$config$require_packages, library, character.only = TRUE)
        }
    },

    validate_assets = function() {
        assets <- get_template_and_shared_assets()

        sapply(assets$template, function(asset){
            path <- file.path(internal$file$paths$template_assets, asset)
            if (!file.exists(path)) stop(asset, " not found at: ", path, call. = FALSE)
        })

        sapply(assets$shared, function(asset){
            path <- file.path(internal$file$paths$shared_assets, asset)
            if (!file.exists(path)) stop(asset, " not found at: ", path, call. = FALSE)
        })
    },

    get_template_and_shared_assets = function() {
        local_assets <- grep("^http://", c(internal$config$styles, internal$config$scripts), value = TRUE, invert = TRUE)
        if (length(local_assets) > 0){
            shared_assets <- grep("^\\$shared/", local_assets, value = TRUE)
            if (length(shared_assets) > 0){
                template_assets <- setdiff(local_assets, shared_assets)
                shared_assets <- str_match(shared_assets, "^\\$shared/(.+)")[,2]
            } else {
                template_assets <- local_assets
                shared_assets <- NULL
            }
            assets <- list(template = template_assets, shared = shared_assets)
        } else {
            assets <- NULL
        }

        assets
    }

)