From b5f9749d75aba8c00beada3a612bbdd57f8ffc58 Mon Sep 17 00:00:00 2001
From: Ben Menasha <benmenasha@gmail.com>
Date: Tue, 10 Nov 2015 14:25:26 -0500
Subject: [PATCH] use URI::Template to Level 2 RFC 6570 URI Template
 parameters.

Some API discovery documents (like Cloud Pub/Sub API) use level 2 url parameters like

"list": {
   "id": "pubsub.projects.topics.list",
   "path": "v1/{+project}/topics",
   "httpMethod": "GET",
...

The {+project} parameter above implies "Reserved Expansion". To support it and other
more complex URI parameters use the URI::Template per module.

Additionally, was getting an error when a body was not supplied in a request that
did not need a body, so check for that case.
---
 META.json                |  4 ++--
 cpanfile                 |  1 +
 lib/Google/API/Method.pm | 10 ++++++++--
 3 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/META.json b/META.json
index 29d2598..6c0594e 100644
--- a/META.json
+++ b/META.json
@@ -42,7 +42,8 @@
             "JSON::WebToken" : "0",
             "LWP::Protocol::https" : "0",
             "URI" : "0",
-            "URI::Escape" : "0"
+           "URI::Escape" : "0",
+           "URI::Template" : "0"
          }
       },
       "test" : {
@@ -77,4 +78,3 @@
       "shigeta <shigeta@typhoon.(none)>"
    ]
 }
-
diff --git a/cpanfile b/cpanfile
index dc8d2ba..e6de74a 100644
--- a/cpanfile
+++ b/cpanfile
@@ -1,5 +1,6 @@
 requires 'URI';
 requires 'URI::Escape';
+requires 'URI::Template';
 requires 'HTTP::Request';
 requires 'JSON';
 requires 'JSON::WebToken';
diff --git a/lib/Google/API/Method.pm b/lib/Google/API/Method.pm
index fba3c9b..44246c0 100644
--- a/lib/Google/API/Method.pm
+++ b/lib/Google/API/Method.pm
@@ -7,6 +7,7 @@ use Encode;
 use HTTP::Request;
 use URI;
 use URI::Escape qw/uri_escape/;
+use URI::Template;
 
 sub new {
     my $class = shift;
@@ -28,7 +29,12 @@ sub execute {
             $required_param{$p} = delete $self->{opt}{body}{$p};
         }
     }
-    $url =~ s/{([^}]+)}/uri_escape(delete $required_param{$1})/eg;
+    my $template = URI::Template->new($url);
+    $url = $template->process( %required_param );
+    # remove from required_param all variables in the url template (the path
+    # variables)
+    delete @required_param{$template->variables()};
+
     my $uri = URI->new($url);
     my $request;
     if ($http_method eq 'POST' ||
@@ -39,7 +45,7 @@ sub execute {
         $request = HTTP::Request->new($http_method => $uri);
         # Some API's (ie: admin/directoryv1/groups/delete) require requests 
         # with an empty body section to be explicitly zero length.
-        if (%{$self->{opt}{body}}) {
+        if ($self->{opt}{body} && %{$self->{opt}{body}}) {
             $request->content_type('application/json');
             $request->content($self->{json_parser}->encode($self->{opt}{body}));
         } else {