Sometimes you want be able to trigger a jenkins job whevever you merge to master.
Fortunately there is a very useful Jenkins Plugin called Generic Webhook
Trigger Plugin to help.
This plugin is not specific to GitHub. It should work with any service that can
post to a webhook.
The plugin let's you parse the JSON payload using either JSONPath or XPath; it even let's you set up key values based on the POST Headers or URL arguments.