R/get.current.packages.R

In groundhog: Version-Control for CRAN, GitHub, and GitLab Packages

get.current.packages <- function(type) {
  
  #path to local copy of available packages
    main_folder <-  paste0(path.expand("~"), "/R_groundhog/")
    ap_file_path <- paste0(main_folder , "available_packages_" , type , "_" , get.rversion() , "_" , Sys.Date() , ".rds")

  #Delete  available.packages files older than 1 hour
    cookie_files <- list.files(main_folder)
    for (filek in cookie_files)
      {
      filek_path <- paste0(main_folder , filek)             #full path to file
      pos.ap_file <- regexpr('available_packages', filek)   #>0 if file contains the words available_packages
      age <- as.numeric(difftime(Sys.time() , file.info(filek_path)$mtime,units='mins'))
      if (pos.ap_file>0 & age>60) unlink(filek_path)        #Delete available_package files older than 60 minutes
    }
    
	#If file with today's and current R version, use it, bypassing slow available.packages() command
    if (file.exists(ap_file_path)) {
        current.packages <- readRDS(ap_file_path)
        } else {
  #Else get available packages to see if each attempted to install is new
      current.packages <- tryCatch({
          data.frame(utils::available.packages(type = type)[, c(1, 2)],stringsAsFactors = FALSE,row.names=NULL)
        },
        error = function(e) NULL)
		
        if (is.null(current.packages)) {
			#Make empty available packages if offline or if older version of R being used to current packages is not available.	
			current.packages <- data.frame(Package="", Version="", stringsAsFactors=FALSE)
			
        }
	#If current packages is not empty, create pkg_vrs for it
        if (nrow(current.packages)>0) {
			current.packages$pkg_vrs <- paste0(current.packages$Package, "_", current.packages$Version)
			}
			
        saveRDS(current.packages, ap_file_path, version=2, compress=FALSE)
    } #End if file found
    
  return(current.packages)
   
  } #ENd function