Fix invalid api path and test

Author: kimoto

lib/line/bot/api.rb

@@ -17,6 +17,7 @@
 module Line
   module Bot
     module API
+      DEFAULT_OAUTH_ENDPOINT = "https://api.line.me"
       DEFAULT_ENDPOINT = "https://api.line.me/v2"
       DEFAULT_BLOB_ENDPOINT = "https://api-data.line.me/v2"
       DEFAULT_LIFF_ENDPOINT = "https://api.line.me/liff/v1"

lib/line/bot/client.rb

@@ -55,6 +55,10 @@ def endpoint
         @endpoint ||= API::DEFAULT_ENDPOINT
       end
 
+      def oauth_endpoint
+        @oauth_endpoint ||= API::DEFAULT_OAUTH_ENDPOINT
+      end
+
       def blob_endpoint
         return @blob_endpoint if @blob_endpoint
 
@@ -122,7 +126,7 @@ def issue_channel_access_token_21(jwt)
           client_assertion: jwt
         )
         headers = { 'Content-Type' => 'application/x-www-form-urlencoded' }
-        post(endpoint, endpoint_path, payload, headers)
+        post(oauth_endpoint, endpoint_path, payload, headers)
       end
 
       # Revoke channel access token v2.1
@@ -141,7 +145,7 @@ def revoke_channel_access_token_21(access_token)
           access_token: access_token
         )
         headers = { 'Content-Type' => 'application/x-www-form-urlencoded' }
-        post(endpoint, endpoint_path, payload, headers)
+        post(oauth_endpoint, endpoint_path, payload, headers)
       end
 
       # Get all valid channel access token key IDs v2.1
@@ -153,14 +157,14 @@ def get_channel_access_token_key_ids_21(jwt)
         channel_id_required
         channel_secret_required
 
-        endpoint_path = '/oauth2/v2.1/tokens/kid'
         payload = URI.encode_www_form(
-          grant_type: 'client_credentials',
           client_assertion_type: 'urn:ietf:params:oauth:client-assertion-type:jwt-bearer',
           client_assertion: jwt
         )
+        endpoint_path = "/oauth2/v2.1/tokens/kid?#{payload}"
+
         headers = { 'Content-Type' => 'application/x-www-form-urlencoded' }
-        post(endpoint, endpoint_path, payload, headers)
+        get(oauth_endpoint, endpoint_path, headers)
       end
 
       # Push messages to a user using user_id.

spec/line/bot/client_channel_token_spec.rb

@@ -73,7 +73,7 @@ def generate_client
   end
 
   it 'issues an oauth access token v2.1' do
-    uri_template = Addressable::Template.new Line::Bot::API::DEFAULT_ENDPOINT + '/oauth2/v2.1/token'
+    uri_template = Addressable::Template.new Line::Bot::API::DEFAULT_OAUTH_ENDPOINT + '/oauth2/v2.1/token'
     stub_request(:post, uri_template).to_return { |request| {body: ISSUE_CHANNEL_ACCESS_TOKEN_21_CONTENT, status: 200} }
 
     client = generate_client
@@ -88,7 +88,7 @@ def generate_client
   end
 
   it 'revokes the oauth access token v2.1' do
-    uri_template = Addressable::Template.new Line::Bot::API::DEFAULT_ENDPOINT + '/oauth2/v2.1/revoke'
+    uri_template = Addressable::Template.new Line::Bot::API::DEFAULT_OAUTH_ENDPOINT + '/oauth2/v2.1/revoke'
     stub_request(:post, uri_template).to_return { |request| {body: '', status: 200} }
 
     client = generate_client
@@ -99,8 +99,8 @@ def generate_client
   end
 
   it 'get all valid channel access token key ids v2.1' do
-    uri_template = Addressable::Template.new Line::Bot::API::DEFAULT_ENDPOINT + '/oauth2/v2.1/tokens/kid'
-    stub_request(:post, uri_template).to_return { |request| {body: GET_CHANNEL_ACCESS_TOKEN_KEY_IDS_21_CONTENT, status: 200} }
+    uri_template = Addressable::Template.new Line::Bot::API::DEFAULT_OAUTH_ENDPOINT + "/oauth2/v2.1/tokens/kid?client_assertion=jwt_string&client_assertion_type=urn:ietf:params:oauth:client-assertion-type:jwt-bearer"
+    stub_request(:any, uri_template).to_return { |request| {body: GET_CHANNEL_ACCESS_TOKEN_KEY_IDS_21_CONTENT, status: 200} }
 
     client = generate_client