Absolute Path Dependencies

[markegge]

In my use case, I'm displaying a Leaflet Map R Object created in one environment in a Shiny dashboard in a different environment. There is considerably processing that happens to create the Leaflet Map R Object, which is not suitable for the dashboard deployment environment.

In plugin-providers.R and other files the absolute paths of the dependencies (e.g. /Library/Frameworks/R.framework/Versions/3.4/Resources/library/leaflet/htmlwidgets/lib/leaflet-providers) are written into the object:

leafletProviderDependencies <- function() {
  list(
    htmltools::htmlDependency(
      "leaflet-providers",
      "1.0.27",
      system.file("htmlwidgets/lib/leaflet-providers", package = "leaflet"),
      script = "leaflet-providers.js"
    ),
    ....
}

Trying to load a map object created on one platform on different platform produces errors like the following:

Error in normalizePath: path[1]="/Library/Frameworks/R.framework/Versions/3.4/Resources/library/leaflet/htmlwidgets/lib/leaflet-providers": No such file or directory
Stack trace (innermost first):
    83: h
    82: .handleSimpleError
    81: normalizePath
    80: addResourcePath
    79: FUN
    78: lapply
    77: origRenderFunc
    76: output$scores_map
    75: ..stacktraceon..
...
     1: runApp

To prevent this error, store the relative path of the dependency rather than the absolute path. Currently, my work-around when loading a saved map object looks like (this is not a good solution, but works for my needs):

data("my_map.Rda") # reads in my_map, a stored Leaflet Map Object
# fix an isssue where these dependencies are hard coded in the stored R objects
my_map$dependencies[[1]]$src$file <- normalizePath(paste0(.libPaths()[1], "/leaflet/htmlwidgets/lib/leaflet-providers"))
my_map$dependencies[[2]]$src$file <- normalizePath(paste0(.libPaths()[1], "/leaflet/htmlwidgets/plugins/leaflet-providers-plugin"))

Thanks!