How can New Relic tap into my app with a simple install? How does it know all the methods, requests, etc?
It works for RoR, PHP, etc.
Can anyone explain the technology behind it? I'm interested in tapping into my Rails app, but I want to do so smoothly like New Relic.
Thanks
In a general way, New Relic's gem inserts kinda middleware in your web framework, and collects data from your endpoint (think as a rails route) until it's response. After every "harvesting time" (defaults to 60 seconds), it sends a post request to NR services with this data. You can also tailor data you need with Custom Metrics, Custom Events. Is also possible to do queries with NRQL and build graphs with that (like you would do in Graphana). They have a customize service for Wordpress too, but is a bit messy in the start. Some options if you want to save some money is configure cloudwatch + datadog, but I would give a shot to their service if uptime is crucial for your app.
If you’re already familiar with New Relic’s application monitoring then you probably know about New Relic’s agents that run in-process on web apps collecting and reporting all sorts of details about whats happening in the app. RUM leverages the agents to dynamically inject JavaScript into pages as they are built. The injected JavaScript collects timing information in the browser and contains details that identify the specific app and web transaction processed on the backend as well as how time was spent in the app for each request. When a page completes loading in an end user’s browser, the information is sent back to New Relic asynchronously – so it doesn’t effect page load time.
You can turn RUM on/off via your application settings in New Relic. As well, you can turn RUM on/off via the agent’s configuration file (newrelic.yml – a ‘browser_monitoring auto_instrument’ flag has been introduced).
The agents have been enhanced to automatically inject JavaScript into the HTML pages so using RUM is as simple as checking the checkbox on the New Relic control panel. However, if you’d prefer more control, you can use New Relic’s Agent API to generate the JavaScript and thus control exactly when and where the header and footer scripts are included.
