From 0584b6e81c0a316f31d79970432e63442e8a4d1b Mon Sep 17 00:00:00 2001
From: wfmackey <william.mackey@grattaninstitute.edu.au>
Date: Fri, 15 Oct 2021 08:07:07 +1100
Subject: [PATCH] add read_absmaps caching

re #63
---
 R/read_absmaps.R                   | 28 ++++++++++++++++++----
 man/anzsco2009.Rd                  |  2 +-
 man/read_absmap.Rd                 | 10 +++++++-
 tests/testthat/test-read_absmaps.R | 37 +++++++++++++++++++++++++-----
 4 files changed, 64 insertions(+), 13 deletions(-)

diff --git a/R/read_absmaps.R b/R/read_absmaps.R
index d73aedf..299e9b7 100644
--- a/R/read_absmaps.R
+++ b/R/read_absmaps.R
@@ -16,6 +16,8 @@
 #' If TRUE, `strip_year_suffix` is run before returning the object, removing
 #' the `_year` suffix from variable names.
 #'
+#' @param export_dir path to a directory to store the desired sf object. \code{tempdir()} by default.
+#'
 #' @return an sf object.
 #'
 #'
@@ -29,11 +31,12 @@
 #'
 #' @export
 #'
-#'
+
 read_absmap <- function(name = NULL,
                         area = NULL,
                         year = NULL,
-                        remove_year_suffix = FALSE) {
+                        remove_year_suffix = FALSE,
+                        export_dir = tempdir()) {
 
   if (all(is.null(name), is.null(area), is.null(year))) {
     stop("Please enter a name (eg name = 'sa32016') or an area/year combination (eg area = 'sa3', year = '2016').")
@@ -47,6 +50,10 @@ read_absmap <- function(name = NULL,
     warning("Both name and area/year entered. Defaulting to name value: ", name)
   }
 
+  if (!dir.exists(export_dir)) {
+    stop("export_dir provided does not exist: ", export_dir)
+  }
+
   # Define name
   if (is.null(name)) name <- paste0(area, year)
   name <- stringr::str_to_lower(name)
@@ -56,9 +63,19 @@ read_absmap <- function(name = NULL,
   url <- paste0(base_url, name, ".rda")
 
   # download to temporary file
-  out_path <- tempfile(fileext = ".rda")
-  download.file(url,
-                destfile = out_path)
+  out_path <- file.path(export_dir, paste0(name, ".rda"))
+
+  if (!file.exists(out_path)) {
+    download.file(url,
+                  destfile = out_path)
+  } else {
+    if (stringr::str_detect(export_dir, "var.folders")) {
+      message("Reading ", name, " file found in temporary folder")
+    } else {
+      message("Reading ", name, " file found in ", export_dir)
+    }
+
+  }
 
   load(out_path)
 
@@ -69,3 +86,4 @@ read_absmap <- function(name = NULL,
   return(d)
 
 }
+
diff --git a/man/anzsco2009.Rd b/man/anzsco2009.Rd
index 69195b9..d7f1c1b 100644
--- a/man/anzsco2009.Rd
+++ b/man/anzsco2009.Rd
@@ -3,7 +3,7 @@
 \docType{data}
 \name{anzsco2009}
 \alias{anzsco2009}
-\title{ANZSCO}
+\title{ANZSCO 2009}
 \format{
 A \code{tibble} with 11 variables:
 \describe{
diff --git a/man/read_absmap.Rd b/man/read_absmap.Rd
index b319cf7..1c8e087 100644
--- a/man/read_absmap.Rd
+++ b/man/read_absmap.Rd
@@ -4,7 +4,13 @@
 \alias{read_absmap}
 \title{Read ABS geographic data}
 \usage{
-read_absmap(name = NULL, area = NULL, year = NULL, remove_year_suffix = FALSE)
+read_absmap(
+  name = NULL,
+  area = NULL,
+  year = NULL,
+  remove_year_suffix = FALSE,
+  export_dir = tempdir()
+)
 }
 \arguments{
 \item{name}{a character string containing absmapsdata file names in [\code{area}][\code{year}] format, eg "sa42016"; "gcc2021".
@@ -20,6 +26,8 @@ See full list at https://github.com/wfmackey/absmapsdata.}
 \item{remove_year_suffix}{logical defaulting to FALSE.
 If TRUE, `strip_year_suffix` is run before returning the object, removing
 the `_year` suffix from variable names.}
+
+\item{export_dir}{path to a directory to store the desired sf object. \code{tempdir()} by default.}
 }
 \value{
 an sf object.
diff --git a/tests/testthat/test-read_absmaps.R b/tests/testthat/test-read_absmaps.R
index 393bef0..3ae4d36 100644
--- a/tests/testthat/test-read_absmaps.R
+++ b/tests/testthat/test-read_absmaps.R
@@ -1,7 +1,8 @@
-test_that("read_absmaps() works", {
+test_that("read_absmaps() retrieves objects", {
 
   expect_type(read_absmap("sa42016"), "list")
-  expect_type(read_absmap("SA42016"), "list")
+  expect_identical(read_absmap("SA42016"),
+                   read_absmap("sa42016"))
 
   expect_identical(names(read_absmap("state2021")),
                    c("state_code_2021",
@@ -10,16 +11,40 @@ test_that("read_absmaps() works", {
                      "cent_lat",
                      "cent_long",
                      "geometry"))
+})
 
-  expect_identical(names(read_absmap("SA32016")),
-                   c("sa3_code_2016", "sa3_name_2016", "sa4_code_2016",
-                     "sa4_name_2016", "gcc_code_2016", "gcc_name_2016",
-                     "state_code_2016", "state_name_2016", "areasqkm_2016", "cent_long",
+test_that("read_absmaps() remove_year_suffix param works", {
+  expect_identical(names(read_absmap("sa42016", remove_year_suffix = TRUE)),
+                   c("sa4_code", "sa4_name", "gcc_code", "gcc_name",
+                     "state_code", "state_name", "areasqkm", "cent_long",
                      "cent_lat", "geometry"))
+})
+
 
+test_that("read_absmaps() input checking works", {
   # errors
   expect_error(read_absmap(), regexp = "Please")
   expect_error(read_absmap(area = "sa2"), regexp = "Please")
   expect_error(read_absmap(year = 2011), regexp = "Please")
+  expect_error(read_absmap(name = "sa42021", export_dir = "this-doesnt-exist"),
+               regexp = "does not exist")
+
+})
+
+test_that("caching for read_absmaps() works", {
+
+  new_dir <- file.path(tempdir(), "test-data")
+  dir.create(new_dir)
+
+  read_absmap("sa42021")
+  # will be cached
+  expect_message(read_absmap("sa42021"), regexp = "Reading")
+
+  # will have to download again
+  expect_silent(read_absmap("sa42021", export_dir = new_dir))
+  # will be cached
+  expect_message(read_absmap("sa42021", export_dir = new_dir))
+
+  unlink(new_dir)
 
 })