From ef8cc222d2bc38aa47bba8404eb5f60cb5c16d43 Mon Sep 17 00:00:00 2001
From: Marcin <ms32035@gmail.com>
Date: Tue, 20 Sep 2016 21:58:09 +0000
Subject: [PATCH] add GetFitOauth2Token function

---
 .gitignore                          |  1 +
 RGoogleFit/.Rbuildignore            |  1 +
 RGoogleFit/DESCRIPTION              |  5 +--
 RGoogleFit/NAMESPACE                |  2 ++
 RGoogleFit/NEWS                     |  9 ++++++
 RGoogleFit/R/GetFitOAuth2Token.R    | 47 +++++++++++++++++++++++++++++
 RGoogleFit/R/RGoogleFit-package.R   |  2 +-
 RGoogleFit/R/Utils.R                |  5 ++-
 RGoogleFit/man/GetFitOauth2Token.Rd | 14 +++++++++
 9 files changed, 82 insertions(+), 4 deletions(-)
 create mode 100644 RGoogleFit/NEWS
 create mode 100644 RGoogleFit/R/GetFitOAuth2Token.R
 create mode 100644 RGoogleFit/man/GetFitOauth2Token.Rd

diff --git a/.gitignore b/.gitignore
index 3de7b17..3e45267 100644
--- a/.gitignore
+++ b/.gitignore
@@ -5,3 +5,4 @@
 RGoogleFit.Rproj
 RGoogleFit.Rcheck
 *.tar.gz
+.httr-oauth
\ No newline at end of file
diff --git a/RGoogleFit/.Rbuildignore b/RGoogleFit/.Rbuildignore
index 91114bf..900464a 100644
--- a/RGoogleFit/.Rbuildignore
+++ b/RGoogleFit/.Rbuildignore
@@ -1,2 +1,3 @@
 ^.*\.Rproj$
 ^\.Rproj\.user$
+.httr-oauth
\ No newline at end of file
diff --git a/RGoogleFit/DESCRIPTION b/RGoogleFit/DESCRIPTION
index 3c414c0..1a5396c 100644
--- a/RGoogleFit/DESCRIPTION
+++ b/RGoogleFit/DESCRIPTION
@@ -1,7 +1,7 @@
 Package: RGoogleFit
 Type: Package
 Title: R Interface to Google Fit API
-Version: 0.1.0
+Version: 0.2.0
 Author: Marcin Szymanski
 Maintainer: Marcin Szymanski <ms32035@gmail.com>
 Description: Provides interface to Google Fit REST API v1 (see <https://developers.google.com/fit/rest/v1/reference/>). 
@@ -11,7 +11,8 @@ Depends:
     R (>= 3.0),
     RCurl,
     jsonlite,
-    bit64
+    bit64,
+    httr
 Imports:
     utils
 RoxygenNote: 5.0.1
diff --git a/RGoogleFit/NAMESPACE b/RGoogleFit/NAMESPACE
index 30806ab..cd26925 100644
--- a/RGoogleFit/NAMESPACE
+++ b/RGoogleFit/NAMESPACE
@@ -3,8 +3,10 @@
 export(GetFitDataset)
 export(GetFitDatasource)
 export(GetFitDatasources)
+export(GetFitOauth2Token)
 export(NanosToPOSIXct)
 import(RCurl)
 import(bit64)
+import(httr)
 import(jsonlite)
 importFrom(utils,URLencode)
diff --git a/RGoogleFit/NEWS b/RGoogleFit/NEWS
new file mode 100644
index 0000000..81c0e07
--- /dev/null
+++ b/RGoogleFit/NEWS
@@ -0,0 +1,9 @@
+RGoogleFit 0.2.0
+----------------------------------------------------------------
+
+* new function GetFitOauth2Token to simplify OAuth2 authentication
+
+RGoogleFit 0.1.0
+----------------------------------------------------------------
+
+* initial release
\ No newline at end of file
diff --git a/RGoogleFit/R/GetFitOAuth2Token.R b/RGoogleFit/R/GetFitOAuth2Token.R
new file mode 100644
index 0000000..3ee9165
--- /dev/null
+++ b/RGoogleFit/R/GetFitOAuth2Token.R
@@ -0,0 +1,47 @@
+#' @title GetFitOauth2Token
+#' @rdname GetFitOauth2Token
+#' @description
+#' Retrieves or refreshes an OAuth2 token. Two options must be set:
+#' \code{RGoogleFit.client_id}
+#' \code{RGoogleFit.client_secret}
+#' @export
+GetFitOauth2Token <- function() {
+  client_id = getOption('RGoogleFit.client_id')
+  client_secret = getOption('RGoogleFit.client_secret')
+  
+  assert(!is.null(client_id),
+         'Please set \'RGoogleFit.client_id\' option')
+  assert(!is.null(client_secret),
+         'Please set \'RGoogleFit.client_secret\' option')
+  
+  oauth2_token <- get0('RGoogleFit.token')
+  
+  if (!is.null(oauth2_token)) {
+    if (!oauth2_token$validate()) {
+      oauth2_token$refresh()
+    }
+    
+  }
+  else
+  {
+    oauth2_token <- oauth2.0_token(
+      endpoint = oauth_endpoints("google"),
+      app = oauth_app(
+        "google",
+        key = getOption("RGoogleFit.client_id"),
+        secret = getOption("RGoogleFit.client_secret")
+      ),
+      scope = c(
+        "https://www.googleapis.com/auth/fitness.activity.read",
+        "https://www.googleapis.com/auth/fitness.location.read"
+      ) ,
+      use_oob = FALSE,
+      cache = TRUE
+    )
+  }
+  
+  assign('RGoogleFit.token', oauth2_token)
+  
+  return(oauth2_token$credentials$access_token)
+  
+}
\ No newline at end of file
diff --git a/RGoogleFit/R/RGoogleFit-package.R b/RGoogleFit/R/RGoogleFit-package.R
index de0cc78..5d90ee3 100644
--- a/RGoogleFit/R/RGoogleFit-package.R
+++ b/RGoogleFit/R/RGoogleFit-package.R
@@ -8,6 +8,6 @@
 #'
 #' @name RGoogleFit-package
 #' @docType package
-#' @import RCurl jsonlite bit64
+#' @import RCurl jsonlite bit64 httr
 #' @importFrom utils URLencode
 invisible(NULL)
diff --git a/RGoogleFit/R/Utils.R b/RGoogleFit/R/Utils.R
index 58880d3..2593262 100644
--- a/RGoogleFit/R/Utils.R
+++ b/RGoogleFit/R/Utils.R
@@ -43,4 +43,7 @@ NanosToPOSIXct <- function(nanos) {
   )
   
 }
-  
\ No newline at end of file
+
+assert <- function (expr, error) {
+  if (! expr) stop(error, call. = FALSE)
+}
\ No newline at end of file
diff --git a/RGoogleFit/man/GetFitOauth2Token.Rd b/RGoogleFit/man/GetFitOauth2Token.Rd
new file mode 100644
index 0000000..00dae0c
--- /dev/null
+++ b/RGoogleFit/man/GetFitOauth2Token.Rd
@@ -0,0 +1,14 @@
+% Generated by roxygen2: do not edit by hand
+% Please edit documentation in R/GetFitOAuth2Token.R
+\name{GetFitOauth2Token}
+\alias{GetFitOauth2Token}
+\title{GetFitOauth2Token}
+\usage{
+GetFitOauth2Token()
+}
+\description{
+Retrieves or refreshes an OAuth2 token. Two options must be set:
+\code{RGoogleFit.client_id}
+\code{RGoogleFit.client_secret}
+}
+