Setup where to put cache — gar_cache_get

To cache to a file system use memoise::cache_filesystem("cache_folder"), suitable for unit testing and works between R sessions.

The cached API calls do not need authentication to be active, but need this function to set caching first.

gar_cache_get_loc()

gar_cache_empty()

gar_cache_setup(
  mcache = memoise::cache_memory(),
  invalid_func = function(req) {     tryCatch(req$status_code == 200, error =
    function(x) FALSE) }
)

Arguments

mcache	A cache method from memoise.
invalid_func	A function that takes API response, and returns `TRUE` or `FALSE` whether caching takes place. Default cache everything.

Value

TRUE if successful.

Examples


if (FALSE) {

# demo function to cache within
shorten_url_cache <- function(url){
  body = list(longUrl = url)
  f <- gar_api_generator("https://www.googleapis.com/urlshortener/v1/url",
                      "POST",
                      data_parse_function = function(x) x)
 f(the_body = body)

 }

 ## only cache if this URL
 gar_cache_setup(invalid_func = function(req){
      req$content$longUrl == "http://code.markedmondson.me/"
 })

 # authentication
 gar_auth()
 ## caches
 shorten_url_cache("http://code.markedmondson.me")

 ## read cache
 shorten_url("http://code.markedmondson.me")

 ## ..but dont cache me
 shorten_url_cache("http://blahblah.com")

}