Prometheus Metric Parser and Aggregator

Metric Parser

This project has a Java implementation of Prometheus text exposition parser. The parser is able to progressively handle metrics exported in the format specified at Prometheus official site

Metric Aggregator and Gateway

The motivation of having an aggregator is to solve the problem where the source of metrics is not reachable, or is intentially hidden from the Prometheus server. Monitoring web frontend, IoT device, and desktop application are good examples. In this case we need a gateway that is reachable from both the Prometheus server and the subjects to capture and aggregate the metrics.

The MetricAggregator class is to group the metrics by the signature, which is composed of the name and labels. It handles adding, updating, and removing metrics. The MetricAggregatorServlet handles the following HTTP methods:

• GET: List current metrics in Prometheus's text exposition format.
• POST: Upload metrics in Prometheus's text exposition format.
• DELETE: Remove all metrics or metrics older than specified age.