Architecture

Main Concepts

1. Actions like scroll, click, etc. are performed on the page. These actions are defined using the Selenium Web driver wd module. The actions can be simple things like clicking on buttons, scrolling down the page, or can be complex tasks like a merchant checkout workflow.
2. The Metrics are measured when the action is performed. A Metric is a quantifiable numbers that can be used to get an idea of how well the website or a hybrid app is performing. Examples of metrics include mean time for each frame when Scrolling average area that is redrawn on the screen or the rate of memory increase during an activity.
3. Probes are data points collected from browser when an action is performed. The raw data from the probe is converted to Metrics. These are collected from various sources like Chrome Timeline graph, about:tracing, xperf or frequency of events like request animation frame.

Control Flow

1. Load URL.
2. Setup Metrics - eg. initialize counters.
3. Setup Probes - eg. add command line flags to browser, reset logs.
4. Start Metrics - Start the counter
5. Start Probes -
6. Perform Actions - eg. scroll, checkout workflow - selenium commands.
7. As actions are performed, Probes emit data to Metrics
8. Actions end
9. Probes teardown - eg. close connections, read final logs
10. Metrics teardown - eg. calculate statistics from raw data
11. Get results from all metrics