Normalize scopes in the hash; fixes #494

NEWS.md

@@ -1,5 +1,7 @@
 # httr 1.3.1.9000
 
+* Scopes are de-duplicated, sorted, and stripped of names before being hashed. This eliminates a source of hash mismatch that causes new tokens to be requested, even when existing tokens have the necessary scope. (@jennybc, #495)
+
 * The default value of `failure` argument in `parse_http_date()` is set to `structure(NA_real_, class = "Date")` so that the reponse with a "failure" date can be printed out correctly. (@shrektan, #544)
 
 # httr 1.3.1

R/oauth-token.r

@@ -104,7 +104,10 @@ Token <- R6::R6Class("Token", list(
     # endpoint = which site
     # app = client identification
     # params = scope
-    msg <- serialize(list(self$endpoint, self$app, self$params$scope), NULL)
+    msg <- serialize(
+      list(self$endpoint, self$app, normalize_scopes(self$params$scope)),
+      NULL
+    )
 
     # for compatibility with digest::digest()
     paste(openssl::md5(msg[-(1:14)]), collapse = "")
@@ -349,3 +352,7 @@ TokenServiceAccount <- R6::R6Class("TokenServiceAccount", inherit = Token2.0, li
   cache = function(path) self,
   load_from_cache = function() self
 ))
+
+normalize_scopes <- function(x) {
+  setNames(sort(unique(x)), NULL)
+}

tests/testthat/test-oauth-cache.R

@@ -30,13 +30,14 @@ test_that("use_cache() respects options", {
   expect_equal(use_cache(), ".httr-oauth")
 })
 
-test_that("token saved to and restored from cache", {
+test_that("token saved to and restored from cache, scopes normalized in hash", {
   owd <- setwd(tmp_dir())
   on.exit(setwd(owd))
 
   token_a <- Token2.0$new(
     app = oauth_app("x", "y", "z"),
     endpoint = oauth_endpoints("google"),
+    params = list(scope = c(a = "a", "b")),
     cache_path = ".tmp-cache",
     credentials = list(a = 1)
   )
@@ -45,6 +46,7 @@ test_that("token saved to and restored from cache", {
   token_b <- Token2.0$new(
     app = oauth_app("x", "y", "z"),
     endpoint = oauth_endpoints("google"),
+    params = list(scope = c(b = "b", "a")),
     cache_path = ".tmp-cache"
   )